Ms Release Note

Maxsurf v13.01 Release Note

Maxsurf 13.01 18 January 2008 Windows Release Note This release note describes the release version 13.01 of the Maxsurf suite of software. This release will run on Windows 2000/XP/2003/Vista. Contents

Differences between 13 and 13.01 ...........................................................................3 IMPORTANT CHANGES.......................................................................................4

Version 13 Beta installations .........................................................................4 Version 13 compatibility with version 12......................................................4 Hydromax loadcase column order .................................................................4 Hydromax Default Salt Water Density ..........................................................4 Workshop Part table column order ................................................................4

All Programs ............................................................................................................5 New installers ................................................................................................5 Windows Vista and 64-bit Support................................................................5 Bug fixes and minor changes.........................................................................6

Maxsurf ....................................................................................................................7 Learning Maxsurf ..........................................................................................7 Properties Pane ..............................................................................................7 Rendering Options .......................................................................................10 Generate TriMesh Surface from Markers ....................................................12 About TriMesh surfaces...............................................................................12 TriMesh Surface Concepts...........................................................................13 TriMesh Surface Procedures........................................................................18 Loading a TriMesh into Hydromax .............................................................24 TriMesh Examples .......................................................................................24 TriMesh Useful Marker Commands ............................................................25 TriMesh common problems and how to fix them........................................29 Grid Spacing dialog .....................................................................................32 Maxsurf Menu Changes...............................................................................33 Bug fixes and minor changes.......................................................................34

Hydromax...............................................................................................................36 Fluid densities ..............................................................................................36 Streaming the Report to Word .....................................................................36 Loadcase Window........................................................................................37 Floodable length graph ................................................................................41 New stability criteria....................................................................................41 Bug fixes and minor changes.......................................................................42

Workshop ...............................................................................................................44 Workshop Part table column order ..............................................................44 Surface association with frames...................................................................44 Triangular Plates ..........................................................................................45 Workshop Menu Changes............................................................................46 Bug fixes and minor changes.......................................................................46

Seakeeper ...............................................................................................................48 Roll motions of catamarans .........................................................................48 Results saving ..............................................................................................49 Additional remote location calculations ......................................................49 Bug fixes and minor changes.......................................................................53

SPAN .....................................................................................................................54 Bug fixes and minor changes.......................................................................54

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Prefit.......................................................................................................................55 Bug fixes and minor changes.......................................................................55

Hullspeed ...............................................................................................................56 Hydrolink ...............................................................................................................56 Problem Reports.....................................................................................................57

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Differences between 13 and 13.01 Export dxf now has the option to export as polylines with arcs for all 2D and 3D

drawings. The option is available from the dxf file export dialog. If this option is chosen the user needs to set a maximum radius value. All arcs with radius smaller than this value will be exported as dxf arc entities. All arcs with radius greater than this value will be exported as polylines.

Trimming curves may now be displayed on plate expansions. A bug that caused trimming to be lost when changing between high and highest

precision in rare cases has been fixed.

Snap stringer pt to edges algorithms has been improved. An infrequent bug causing Workshop to crash during shell expansion drawing has

been fixed.

A bug which caused the plate UCS not to align correctly with selected plate mesh points has been fixed.

Hydromax crash when dragging some criteria in the criteria window is resolved. Control Point Property window works correctly in none Meter units. Surface Type drop down items are no longer repeated in the Surface Property

window.

Toolbar preferences are no longer reset when no copy protection device is found, when starting the program.

Lock now works correctly in the Surface Properties dialog. Assembly pane no longer flickers when pane is undocked When exporting stringers to ShipCAM files there is now an option to reduce the

number of stringer points exported which inturn reduces the file size (by approximately half):

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IMPORTANT CHANGES

Version 13 Beta installations Version 13 beta testers will have to uninstall their beta version before installing the

final version 13.

Version 13 compatibility with version 12

Hydromax Due to new ways to add comment lines and sub-subtotals in version 13, the user should carefully check that the total weight of a loadcase saved in V13 and opened in V12 is the same. Also check this after doing an Update Loadcase. Also see: Loadcase compatibility between v12.xx and v13. Any sub-subtotals in V13 or comments which start with a space or apostrophe character will be interpreted as loads in V12; however, they will have zero weight so the total will not be affected. Thus, if backward compatibility with V12 is required, sub-subtotals should not be used and comments should either be completely empty or have a full-stop as the first character.

Workshop Structures created in V13 can not be opened in V12. To open a V13 structure in V12, you should use the Save as Version 12 function in the File | Export menu.

Hydromax loadcase column order The order of the Hydromax loadcase columns has been changed. The vertical and offset ordinate columns have been switched. Also see: Hydromax loadcase column order on page 37.

Hydromax Default Salt Water Density The default relative density for both Sea Water and Ballast water has been changed from 1.0252 to 1.0250. This will give you slightly different analyses results in V13. You can manually change the density from the Analysis | Density menu.

Workshop Part table column order The order of the Workshop Part table columns has been changed. The vertical and transverse ordinate columns have been switched.

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All Programs

New installers All Maxsurf applications are now installed using a single installer. This means you no longer have to install each Maxsurf module individually. This installs Maxsurf applications into a directory at C:\Program Files\Maxsurf 13. Note also that it adds shortcuts to Maxsurf under Maxsurf 13 in the Start menu. The new installer will automatically migrate your old settings and libraries from your previous installation. Please see the installation guide on the installation CD or online at: http://www.formsys.com/installation.

Windows Vista and 64-bit Support Maxsurf version 13 is supported on Windows Vista OS as well as on 64-bit computers.

Installation Directory Changes (Vista only) For all operating systems, the software is installed in the

C:\Program Files\Maxsurf ## directory for Maxsurf, or , where ## is the version number. On Windows Vista, some other directories are used as well. See below:

Filetype Vista

Libraries C:\Users\Public\Documents\Maxsurf\Maxsurf## Sample designs C:\Program Files\Maxsurf ## User settings .xml C:\Users\CurrentUser\AppData\Roaming\Maxsurf\

Maxsurf##\MSSettings##.xml

Vista Tips Do not save any data to the c:\ drive or c:\program files directories. Files that are saved to these directories will be virtualised which means that they are stored under your local documents folder. For example: when you open a sample file from the C:\Program Files\Maxsurf directory and save it, it will be moved from the C:\Program Files\ directory to your local user directory. When using the File | Open dialog, virtualised files can be seen in the C:\Program Files\ directory by the local user who saved the file only. Windows explorer does not show virtualised files at all. Confused? See Windows Vista help.

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Bug fixes and minor changes The Application icons have been changed. 3D rotate command may now be initialised via the mouse. Hold the shift key down

while pressing the middle mouse button to rotate the model.

Precision setting is now saved with the model. If a model is saved in highest precision in Maxsurf, it will be opened in highest precision by default. This is also true when porting the design across the different modules such as Hydromax and Workshop.

Maxsurf and Workshop will look for the sections library in the %ProgramFiles%\Maxsurf folder if it fails to find it in the folder where the application was started. % ProgramFiles% is an environment variable that is normally set to C:\Program Files. This means that Maxsurf and Workshop will now find the sections library regardless of the installation directory you may have chosen.

The colour definitions dialog (View | Colour) only lists the colour items relevant to the particular application (rather than all the colours items).

Restore Default Layout now restores the layout of the windows, not just the toolbars.

The Axis Indicator has been added to rendered perspective window. Customised toolbars and layouts no longer get reset when a copy protection

device is not found.

Multiple items are no longer added to the drop down fields of the Surface Properties Window.

The Locked property can now be changed via the Surface Properties Dialog window.

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Maxsurf

Learning Maxsurf There is now a comprehensive training package included in the software called Learning Maxsurf. The training package consists of either a PDF document or a series of web pages featuring step-by-step tutorials supported by videos. The training is useful for new users and will also give a better understanding of key concepts in the program to experienced users. Learning Maxsurf is available online on our website or from your local computer after installing the Learning Maxsurf installer from the installation CD. All information on Learning Maxsurf can be found on the website: http://www.formsys.com/mslearning

From within the Maxsurf application, the training document can be accessed from the Help menu. The Learning Maxsurf command will start the PDF document if Learning Maxsurf has been installed on your computer. In case Learning Maxsurf has not been installed, the online version will be started in your web browser.

Properties Pane A Properties Pane has been introduced to Maxsurf. The Properties Pane allows you to manipulate data of items selected in the view windows.

Opening the Properties Pane The Properties Pane can be shown by selecting Properties from the View menu, or pressing F3 function key on your keyboard.

Properties Pane Options The Properties Pane works very similar to the Assembly Pane in the way that it can be floating, docked or set to auto hide. The Assembly Pane and the Properties Pane can also be docked together into one pane or as tabbed panes.

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http://www.formsys.com/mslearning


Regular docking and floating options for Properties Pane same as for the Assembly Pane.

When you drag the Properties Pane on top of the docked Assembly Pane, you will see the following:

Properties Pane docking position: 1: Above Assembly Pane 2: To the right of Assembly Pane 3: Below Assembly Pane 4: To the left of Assembly Pane 5: To the left of Assembly Pane as a separate pane 6: Underneath the Assembly Pane into a tabbed pane.

Properties Pane docking in the same area as the Assembly Pane has different options.

Properties Pane Video

View a video that will show you the different window layout options for the Assembly Pane and Properties Pane.

Closing the Properties Pane The Properties Pane can be closed by clicking on the cross in the top right of the Pane.

Closing when docked Closing when floating

Using the Properties Pane The Properties Pane in Version 13 can be used to view and modify the properties of the following objects: Object Selection method Surfaces Assembly Pane and rendered Perspective view

Only single surfaces can be selected in this version Control Points Multiple control points selection from any view window Markers Multiple control points selection from any view window Single object selected The image below shows a single control point selected in Perspective view. The Properties Pane can be divided up into two areas that show the following:

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https://www.formsys.com/maxsurf/videos/new-in-version-13/version-13-videos/docking-the-properties-pane-and-assembly-pane#tNRm0Rs248_KRWoSCR9Tcg


1. The object selected. In this case the row 1, column 4 control point on the Bullwark_Trim surface.

2. The properties of the object selected. a. Some fields are greyed out which means they are read-only and cannot be

edited. In case of a control point object, these are the Surface that the control point belongs to and the row and column numbers.

b. The fields that can be edited are the position and the weight of the control point. For example, you can move the control point fwd to 55 m by simply selecting the Long Pos. value field and typing 55. The position of the control point will be updated in the view windows as soon as you hit enter or click out of the Long Pos. value field.

The Properties of the selected control point are listed in the Properties Pane on the left.

Multiple Control Points Selected In the image below multiple control points are selected. The Properties Pane now allows you to modify the properties of the selection, or select one particular object to be modified individually using the drop down in area 1.

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When multiple control points have been selected, you can modify the properties of the selection or switch to individual control points using the drop down.

Values that are the same for all selected objects are shown in area 2 in the Properties Pane. For example: all selected control points in this image share a control point weight 1. You can also modify the properties of this group of control points by typing in the value fields. For example, if you would like all control points to move to a Long Pos. of 60 m, you can simply type 60 in the Long Pos. field and all control points will move as soon as you hit enter or click outside the field. Selecting, viewing and modifying the properties of surfaces and markers works in much the same way.

Note You can not select more than one surface simultaneously.

Using the Properties Pane Video

View a video that will show just a few of the things you can do with the Properties Pane such as identifying surfaces and changing the properties of surfaces, control points and markers.

Rendering Options Some new options have been added to the Rendering Selection dialog that allow you to do more with your model in Rendered view in the Perspective window.

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https://www.formsys.com/maxsurf/videos/new-in-version-13/version-13-videos/using-the-properties-pane#VBCtRCix6dYo5Z84sfnJmA


OpenGL Selection It is now possible to select a surface in rendered mode. This in combination with the Properties Pane - makes it very easy to identify surfaces. Maxsurf now also supports a context menu (right click menu) on rendered surfaces in Perspective view. This right click menu is the same as the right click menu on a surface in the Assembly Pane. This makes it very easy and fast to identify, trim, hide, lock, rename or delete surfaces.

When there are several surfaces directly behind each other, a Select option will appear at the bottom of the right click menu which allows you to select which surface you wish to select. Double clicking on a surface now brings up the Surface Properties dialog. You can use this as an alternative to the properties pane. The colour of the selection highlighting can be set in the View | Colours dialog.

OpenGL Net Colour Coded This displays the colour of the control point net in Rendered view in Perspective window in the colour of the surface. This may be convenient when working on a multi-surface design:

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You can move the control points in rendered view in the perspective window: Select the control point and hold down the left mouse button Move the control point to its new position and release the left mouse button

The rendered surface will be updated as soon as you release the left mouse button.

Generate TriMesh Surface from Markers A TriMesh surface generator has been added to Maxsurf. Find out what this could do for you in the following sections:

About TriMesh surfaces TriMesh Surface Concepts TriMesh Surface Procedures TriMesh Examples TriMesh Useful Marker Commands

About TriMesh surfaces A TriMesh surface is a linear surface made up of triangular facets. It facilitates the analysis of vessels for which section data exists but no NURB surface model is available. The purpose of the TriMesh surface in Maxsurf is to quickly generate a model which can be used for hydrostatic and/or seakeeping analysis in Hydromax, Seakeeper and Hullspeed. It is often the case that line or point data for a vessel exist but a full NURB surface model does not exist. Reverse engineering an accurate NURB surface model from point or line data can be laborious and time consuming. Often the level of smoothness obtained from a NURB surface is not required and a surface made up of linear, triangular facets is sufficient. The aim of the TriMesh surface is to provide a quick route from line or point data to a vessel surface model that may be used for analysis. The accuracy of a TriMesh surface representation of the hullform is dependent on the number of data points used to generate the TriMesh. Because a TriMesh surface is a linear surface made up of triangular facets, it is generally not suitable for construction purposes. This means that, if for example plate expansions and longitudinal stiffener geometry outputs are expected to be required at a later stage in the design process, the Maxsurf and Prefit tools for fitting NURB surfaces to markers should be used.

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TriMesh Surface Concepts TriMesh surfaces can be automatically generated from a set of ordered Markers. Once the tri mesh surface has been created it can be saved in the regular .msd file and opened in Hydromax for stability analysis.

What is a TriMesh Surface? A TriMesh surface is a linear surface made up of triangular facets. It is not a NURB surface, it does not have control points, and it cannot be trimmed with NURB surfaces. The TriMesh surface is not designed to be smooth it follows the input data points (Markers) exactly and is linear between the data points. The Markers should provide sufficient detail for the purpose to which the model is going to be put.

TriMesh Surface Scope At present only one TriMesh surface may be defined in Maxsurf. This effectively limits the vessel type to monohulls, though by carefully preparing the Marker data catamarans can be modelled. Further, any NURB surfaces in the Maxsurf model will override the TriMesh (unless they are internal structure surfaces for tank definition in Hydromax). Problems will often occur where the number of contours on a given section changes. Ideally there should only be one contour on each section. Having said that, bulbous bows and stern bulbs can normally be modelled, though some extra care may be required in marker placement. This is achieved by removing excessively large triangles from the TriMesh surface. In the future it may be possible to have several TriMesh surfaces in the same model thus enabling vessels of greater complexity to be built up.

Markers and TriMesh Surfaces The Marker is the primary object used to create the TriMesh surface. The Markers will become nodes on the surface that are interconnected in such a manner so as to produce a surface comprised of triangular facets. Markers are reference marks displayed on the screen at a specified longitudinal, transverse and vertical position in space. The maximum number of markers you may use is 30000. In practice you will usually use many fewer than this.

An example of Markers defining the starboard side of a round-bilge vessel with bulbous bow.

Marker data may come from a variety of sources; these are described in greater detail later in this document. Some examples are: Lines plan drawing, table of offsets, laser scanner data, other section-based hull definition file, etc. In Maxsurf, Markers can be used for:

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Visual reference point Target points for (semi) automatic fitting of NURB surfaces Automatic generation of TriMesh surfaces

For the purposes of generating a TriMesh surface, the Markers must be structured in a pre-defined manner to facilitate the surface reconstruction. First, the markers must be grouped and then they must be sorted within each group.

Marker Grouping for TriMesh Surfaces The markers should be organised in groups or marker stations. Broadly speaking, the markers need to be organised into transverse sections through the hull. However the only constraints that actually must be followed are:

Each section of markers(called marker station) must be defined in the same direction. The actual direction does not matter, but all the sections must be consistent. For example starting at the keel and going round the hull to the deck edge or deck centreline.

The marker stations need not be planar, thus it is perfectly OK (and actually desirable) to define the bow profile, and in the case of a cruiser-stern vessel to define the stern profile.

The contours must not be self-intersecting or intersect each other. In some instances it is admissible to have contours that just touch, but do not actually intersect. This is achieved by having duplicate markers on the same contour and is useful for defining the forward part of a wave-piercing catamaran (see below):

The contours should have sufficient points to adequately define the geometry (the surface will be linear between the markers).

Longitudinal discontinuities can be defined by two different contours at the same longitudinal position.

The sections are defined sequentially. The sections are indexed incrementally. Each Marker is associated (or: linked) to a given section by the Station index field in the Markers properties dialog. Markers on the same section should all have the same Station index even if they do not lie in the same plane.

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Markers on the same section should all have the same Station index even if they do not lie in the same plane.

If you want the markers to be linked to the corresponding hull section contour line at that longitudinal position, you should use the station index of the section:

In this example st 8 has station index number 9.

A marker that is linked to a hull section contour line will be shown together with that section line in Body Plan view when the view is set to Display | Markers |Markers for Current Station and the Sections are turned off. The control box (top right in Body Plan window) can be used to switch between Sections.

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Markers displayed with the corresponding hull section contour line.

Marker Ordering for TriMesh Surface As mentioned above the markers in every marker station group should be ordered in a consistent manner: for example, always starting on the keel / lower centreline of the vessel and finishing on the deck edge. There are a number of tools to assist with the ordering of markers. These are described in the following sections.

Note There is no UNDO for marker-based commands. When working with markers, it is recommended to save your file regularly; especially before a command that may significantly change your model!

Marker Station Ordering for TriMesh Surfaces Finally, after the markers have been grouped by section and ordered within the section, it is important that the marker sections are sorted by longitudinal position. This has to be done manually by making sure that the station index numbers increase going forward.

Marker Data Sources This section summarises the different data sources and methods that can be used to generate Markers in Maxsurf. Paper-based drawings

With paper based drawings you have two options: 1. If you have access to a digitising tablet and suitable software, digitise the

sections so that you have (longitudinal, horizontal, vertical) coordinate data for all the key points on the design.

2. If you have access to a suitable image scanner, scan in the drawings and load them into Maxsurf. Before loading them, ensure that the scale in the vertical and horizontal directions are the same and that the image is in the same orientation as the Maxsurf views note that the image can only be scaled in Maxsurf, it cannot be rotated or skewed etc. When you have the images in Maxsurf, you can use Maxsurf to digitise marker points along the sections, waterlines and buttocks.

Digital Image If a digital image is available, this can be loaded as a background image in Maxsurf and digitised. The body plan, stem profile and possibly stern profile are the most useful.

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Digitising markers from a scanned image of a paper lines plan.

When entering data in this manner work in a systematic manner, see the Digitising Images in Maxsurf on page 21 in the procedures section below. For a hard-chine vessel, such as that shown above, it is only necessary to insert makers at the key points on the keel, chines and deck edge.

3D DXF If the existing lines plan is in 3D DXF format, it can be read directly into Maxsurf and markers generated automatically. To do this, start a new design, select File | Import | Import DXF markers, select the file and then specify the orientation of the design in the DXF file. Note that when reading in the DXF file all nodes of all poly-lines are converted to markers. It is normally easier to delete all unnecessary lines in the DXF file rather than trying to delete the unwanted markers in Maxsurf. All that is required in Maxsurf are the markers that define the hull.

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2D DXF computer file If you have a 2D DXF lines plan, it is normally quite easy to generate a fairly comprehensive 3D DXF model. This is most easily done in a standard CAD package such as AutoCAD. Start by extracting the body plan and noting the longitudinal positions of each of the sections that are defined in the body plan. Select each section in turn and move it longitudinally so that it is in its correct location. If the drawing is in the traditional format, with the aft sections displayed on the left, you will need to reflect them so that they are all displayed on the right. If full sections are shown, and the hull is symmetrical delete the left hand side of the sections. You can now load the DXF file in and obtain 3D marker points as described in the previous section.

Simple digital lines plan (2D DXF)

Offsets table data Offsets tables may also be used, but this data must be converted into (longitudinal, horizontal, vertical) coordinate data. They should be saved in a tab-delimited format, with one point on each line. They can then be imported into Maxsurf (switch to the Marker window in Maxsurf and select File | Open Markers).

Random point cloud Currently it is not really viable to fit a TriMesh surface to a totally random cloud of data points such as might be generated by a laser scanner or multi-beam sonar system. Some structure needs to be added to the data by organising them in to roughly planar, non-intersecting contours.

TriMesh Surface Procedures This section describes how to create a TriMesh surface in Maxsurf.

TriMesh Video

View a video that will show how you can generate a TriMesh surface from a set of markers in Maxsurf. Click here for the input data that is used in the video.

View a video that will show you how the TriMesh surface can be loaded in Hydromax. Click here for the TriMesh surface design.

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https://www.formsys.com/maxsurf/videos/new-in-version-13/version-13-videos/generating-a-trimesh-surface#ajqdxMTVFQZ7B-WaLKr-6whttp://www.fdsfiles.com/web/videos/TriMeshFit_Start.msdhttps://www.formsys.com/maxsurf/videos/new-in-version-13/version-13-videos/working-with-a-trimesh-in-hydromax#06muTO15S0EFverbY_XaAwhttp://www.fdsfiles.com/web/videos/TriMeshFit_Start_fitted.msd


Create a new design First create a new design File | New

Zero point and Frame of reference It is recommended to avoid changing the zero point or frame of reference after the data has been imported as this will then change the datum as compared with the original data making checking difficult. Set the zero point to match that of the input data. It is generally preferable to use one of the perpendiculars as the longitudinal datum since this is under direct user control and will no change if the surfaces in the model are changed. Once the TriMesh has been generated, you can define the Frame of Reference. It is generally best to enter the data numerically rather than use the automated search buttons (for Baseline and perpendicular position relative to the waterline) as this will ensure that the datum of the original marker data remains uinchanged. Do not change the position of the perpendicular you used to define the longitudinal datum in the Zero Point dialog. If you used amidships for the longitudinal datum, then type in the values for the fwd and aft perpendiculars and ensure that they are of the same magnitude.

Data input Input the data from the original source. If the data is in 3D digital format (DXF lines plan, offsets or section data from some other application for example GHS) then it should be a simple matter of importing the data and ensuring that the directions and orientations are correct. In Maxsurf these are:

Longitudinal, positive forward Transverse, positive starboard Vertical, positive upward

If the data is to be digitised in Maxsurf from a scanned image then skip the Grid section go straight to Digitising Images in Maxsurf When Importing DXF Markers or GHS markers, Maxsurf can automatically generate the grid. The section grid is generated automatically only if no existing sections have been defined. If sections are already defined then imported markers that lie within 1cm of a section will be allocated to that section, otherwise they will be left unallocated.

Generating a Grid The station grid with sections, waterlines and buttocks must be defined and the Markers must be linked to the corresponding sections.

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Although the sections are planar, the Markers associated with each section need not lie on the same plane. Thus Markers defining a sloping transom should all be grouped by the same station index but they will not have the same longitudinal value. The same is true for a stem profile. If you have input Marker data and the section grid has not been setup automatically, it may useful to use the Markers | Generate Grid from Markers command to set up the grid (stations, buttocks and waterlines) for the surface you have just created from the marker point data. Only use this command if the markers are not already sorted into stations and are not correctly ordered on each section. This is because the Generate Grid from Markers command will also sort the markers on the stations it has found. This may be undesirable if the markers are already in the correct order. In which case you should use the Group Markers by Stations command which will give you the option of generating the station grid from the markers:

Stations are generated at the markers longitudinal position; buttocks at their transverse offset; and waterlines at their vertical location:

You have the option of selecting which items of the grid to generate (stations, buttocks and waterlines). For each of these you have the option of deleting and replacing the existing grid data or adding to the existing grid data. You can also specify how many markers must be at the same longitudinal position, transverse offset or vertical location for a station, buttock or waterline (respectively) to be added. Finally, you can specify a tolerance for markers to be considered at the same plane: for example if the Marker plane separation tolerance were set to 0.001mm then markers up to 1mm apart (in longitudinal position, transverse offset or vertical location) would be considered to be in the same plane and the station, buttock or waterline location would be averaged.

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When using the Generate Grid from Markers command this will only add stations for groups of markers that are on a station plane (longitudinal position = constant). It is normally best to set the Minimum number of markers for a station to more than one. Do this if you have a bow profile or raked transom defined by markers otherwise you will get a station for each maker on the stem profile.

Digitising Images in Maxsurf The following procedure should be used to digitise the markers from the scanned drawing or other background image:

1. If the data is to be digitised in Maxsurf from a scanned image, ensure that the zero point is identifiable (and shown on the image) and that a suitable reference point for scaling is available. Also ensure that the image is in the correct orientation, as it cannot be rotated in Maxsurf.

2. Choose a suitable background colour for the image; make it match, as closely as possible the background colour that you normally use in Maxsurf.

3. Load the background image(s) into their corresponding Maxsurf view windows (a body plan is normally sufficient but a profile view, giving the stem profile and shear line can also be useful.

4. Define the zero point and reference point for each image. 5. Define the zero point datum being used (Data | Zero Point dialog). 6. Define the section grid in the Data | Grid spacing dialog. 7. In the body plan view inset box, select the first station to be digitised. This

will set up the correct longitudinal position and Station Index for the markers.

8. Now add markers to define the section. Make sure you always start from the same position and define the new Markers sequentially. It is useful to turn on the Display | Makers | Markers for Current Station and also Display | Makers | Connect Markers Stations.

9. Choose the next section from the inset box and repeat the digitising process remembering to start from the same point on the section.

Notes: Ideally the input lines plan should have all the sections drawn on the starboard side. However, this is not normally the case and there can be some difficulty with digitising markers for the sections drawn on the port side of the hull centreline. Basically any markers that are inserted on the port side of the vessel will have a negative offset. To over come this:

1. Turn the Half display option off or to make the Split section (Grid spacing dialog) the furthest aft section. Otherwise, the negative Markers will be mirrored (for the split display) onto the positive side of the vessel for display purposes.

2. Then insert all the markers on the stern stations on the portside of the vessel and then finally make all the offset values positive rather than negative. The simplest way to do this is to copy the Offset column of the markers to Excel and multiply each by -1 and then paste the data back into Maxsurf.

3. Assuming that the vessel is symmetrical, define the markers for just one side of the hull starting consistently from either the keel, deck edge, or - if the deck is to be included in the TriMesh - from the centreline of the deck.

4. If the vessel is asymmetrical then start every section consistently from either the keel or centreline of the deck and work round the section in the same direction each time.

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Preparing the Marker Data Before you can generate a TriMesh surface, you will have to do the following two steps with your marker data:

1. Group the Markers into Groups of Marker stations. 2. Order the Markers within each Marker Section.

Also see the section on TriMesh Useful Marker Commands on page 25. Step 1. Group Markers into Groups

This step can be skipped if you have used the Generate Grid from Markers command. Starting from the aft end of the vessel, find the station index number for the aft most grid select the markers and select Markers | Marker Properties. Set the Station Index field to for example 1. Moving forward along the length of the hull to the next intended group, select the next set of markers and set the Station Index field to 2. If you wish to view the corresponding hull section contour with this group of markers, the station index number should be the same as the section at that longitudinal position. Also see the concepts section: Marker Grouping for TriMesh Surfaces on page 14. The surface-fitting algorithm requires groups of Marker stations to be sorted by longitudinal position. The Markers | Group Markers by Stations will sort the Markers in the Markers window such that they are listed in the order of their station index. Thus, if the stations are monotonically increasing, this will sort the markers into the correct order. If adding markers graphically, all the markers on the same station may not be consecutively placed in the Marker table. Using the Markers | Group Markers by Stations will fix this problem.

Step 2. Sorting Marker Data It is essential that the markers are grouped by section and that, on each section, the markers are sorted (or: ordered) in a consistent manner. There are a number of tools that can assist in this process should the markers be in the incorrect order. See Re-order Selected Markers on page 26 for details of these functions. Markers that have been assigned to the same Station Index can be sorted for each station using the Sort Marker Stations command from the Markers menu. This sorting uses a nearest neighbour sort, which works in most instances, but can be confounded if the section shape is complex and/or the spacing between markers varies significantly. Also see the concepts section: Marker Ordering for TriMesh Surface on page 16.

Viewing Marker Order To view the connectivity (and ordering) of the markers turn on the Display |

Connect Marker Stations option: Ctrl+J, . This is best done in the Body Plan

view, with the Display | Show Markers for Current Station option selected . The first marker on the section is shown in bold, when the Connect Marker Stations option is turned on.

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The first marker on each section is shown in bold

Generating a TriMesh Surface Once the Markers have been added and sorted, the TriMesh surface may be generated. Use the Markers | Generate TriMesh Surface from Markers command to do this.

TriMesh surface dialog

There are two options: Mirror surface about centreline. This will mirror the surface generated from the

markers across the transverse centreline of the model. Tick this box if you have defined just one half of the vessel. If you have defined markers for both port and starboard halves of the vessel then leave this option unticked.

Delete large triangles. This option is useful if the vessel has a bulbous bow. If this is the case then there will be large triangles generated on the centreline between the top of the bulb and the bow above the bulb. These triangles will only affect wetted surface area calculations but if desired, they can be detected and deleted. You can specify how large the triangles are allowed to be before they are deleted this is done by specifying the number of standard deviations from the mean edge length.

The Generate TriMesh command works on the selected markers. This can be useful when trying to fix a problem simply select all the markers in the adjacent columns (this is most effectively done in the profile view). The TriMesh colour depends on the local orientation: areas that face forward or backwards are red; those areas that face up or down blue; and those that face sideways are green; blending of these colours occurs where the surface faces a composite direction.

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Loading a TriMesh into Hydromax To load a TriMesh into Hydromax you first have to save the TriMesh surface in Maxsurf to create a .msd file. In Hydromax simply go File | Open and select the TriMesh surface. You will see the following Section Calculations Options dialog appear:

You will notice that you are only allowed to use the Maxsurf stations. This is because the triangular facets of the TriMesh surface are linear between the marker stations and it is assumed that you have defined a grid section at each marker station. There is no point in trying to calculate for example 200 regular sections along a TriMesh surface if those sections do not correspond with the marker stations. The surface precision is also irrelevant for TriMesh surfaces because they are linear and since the TriMesh cannot be trimmed or have thickness assigned to it, there options are also irrelevant. Click OK to calculate the section model in Hydromax.

TriMesh Examples The following gives some idea of the types of vessels that can be generated with the TriMesh:

TriMesh surface for container ship with bulbous bow and stern bulb

TriMesh surface for yacht with rudder, fin keel and keel- bulb. Due to some large triangles in the hull, not all the unnecessary triangles between the keel and keel-bulb have been deleted

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TriMesh surface for yacht canoe body

TriMesh surface for chine-hull trawler. Only a small number of sections were defined for this vessel

TriMesh surface for a fishing boat with stepped deck

With careful placement of markers even fairly complex geometries can be modelled with the TriMesh

TriMesh Useful Marker Commands The following commands in the Markers menu are useful when preparing marker data prior to generating a TriMesh surface. Note that in most cases, the command will work on the selected markers only; if no markers are selected, then the command will work on all the markers.

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Generate Grid from Markers Group Markers by Stations Sort Marker Stations Re-order Selected Markers Invert Marker Ordering for Current Station Delete Duplicate Markers Keyboard tools for Sorting Markers Adding markers to an existing section

Generate Grid from Markers This will generate the section grid (and buttock and waterline grid if desired) from the marker locations. The command works on the selected markers; if no markers are selected, all markers will be used. The markers will be allocated the corresponding station indices.

Group Markers by Stations This will change the order of the markers in the markers table and collate all markers with the same station index reference number together in the markers table (without changing the order of the markers for a given station index number). This function will reorder the marker table so that the marker stations will be listed sequentially. The order of the markers on any given station will not be changed. This command is useful if a new station of marker points has been added and the new station has been added out of sequence, at the end of the Marker table. For this command to have the desired effect, the station order (as defined in the Grid Spacing dialog) should be monotonically increasing (or decreasing). When using this command, you can also automatically generate the section grid if desired.

Sort Marker Stations This will sort all markers with the same station index using a nearest neighbour sort. In most monohull vessels this will sort the markers correctly for generating a TriMesh surface. However the nearest neighbour search is not infallible and may fail for catamarans or sections with a bulbous bow. In these cases the order will have to be fine-tuned manually. The command works on the selected markers, or on all the markers if none are selected. The command may be used on just a portion of the markers on a single section if desired. This command is typically used after transverse sections have been defined and a Station Index for each marker has been assigned. It is most useful if the data is completely unstructured: for instance after importing a set of sections made up of many separate polylines.

Re-order Selected Markers This command sorts all markers in a selection in the order in which they were selected. Running this command twice will sort order the markers in the opposite order.

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To re-order a range of markers, select them in the new desired order (from the keel outwards towards the deck edge (or deck centre line) and select Markers | Re-order Selected Markers (Ctrl+Shift+R). If the new order is the reverse of what is required, simply repeat the command without changing the selection, and the order will be reversed.

Markers incorrectly ordered Start selecting Markers in correct order

Start with marker that should be closest to keel in the group

Markers selected in correct order. Use Re-Order Selected Markers command to re-order

Points are now ordered in the selection order, if this is the inverse of what is required, simply repeat the Use Re-Order Selected Markers command without changing the selection.

Note that selecting markers in a selection box will select the markers in their current order. This method can be used to reverse the order of a group of markers:

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Upper markers are in the reverse order

Select them all Use Re-order command to invert their order (you may need to use

the command twice)

Invert Marker Ordering for Current Station This will invert or reverse the ordering of the markers on the current section (as selected in the Body Plan view Inset Box). The marker in bold (when Connect Marker Stations is turned on) is the first marker on the station.

Delete Duplicate Markers This will delete any duplicate markers with the same position (to within a tolerance of 0.5mm) from the selected group of markers (or all the markers, if none are selected).

Keyboard tools for Sorting Markers A single marker can be moved along the ordering by using Ctrl+Cursor keys; left and down keys move the point one positions towards the start of the ordering whilst up and right keys move the point one position towards the end of the ordering; the Home key makes it the first point and the End key makes the it the last point:

Before and after: Moving the selected point one position towards the start of the curve corrects the marker ordering

Adding markers to an existing section When a marker is added, it will be inserted to so as to minimise the increase in section length. This normally ensures that it is inserted in the correct order with respect to the other markers on the station.

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Inserting markers into a station

TriMesh common problems and how to fix them

Unwanted duplicate markers In most cases duplicate markers cause problems. For instance in this catamaran models, duplicate markers on the sharp corner cause the corner detection algorithm to fail. However in some cases duplicate markers are required. To delete duplicates from a range of markers, simply select the range of markers with the selection box and choose Markers | Remove duplicate markers. If no markers are selected duplicates from the entire marker list will be deleted

Duplicate markers causing corner detection to fail

Delete duplicate markers in the corner region of these sections:

Select the markers from which you want to delete duplicates

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Duplicate markers removed: corner detection now works correctly

Connections appear between non-consecutive sections In some cases if you insert markers graphically, although they are inserted into the correct section (ie given the correct station index, they may be in the wrong order in the marker table). This is easily solved with the Markers | Group Markers by Station command which will reorganise the marker table so that the markers will be grouped by station index. The order of the actual markers on a given section will not be changed. For this to work correctly it is imperative that the section grid spacing is monotonic. In the example below, an extra station was added these markers were appended to the end of the Marker table, out of sequence, hence the TriMesh is trying to connect the sections in the wrong order.

Before adding new section

After adding section, markers are out of sequence because added to the end of the Marker table

After Markers | Group Markers by Station markers now appear in the correct order in the Marker table

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An unwanted hole appears in the TriMesh surface Generally it is desirable to remove unusually large triangles from the trimesh this enables bulbous bows and yachts with fin-keels and bulbs to be defined (not to mention multihulls). However if the marker spacing is very irregular, valid triangles that should not be removed are removed resulting in unwanted holes in the surface:

There are two solutions to fix this problem: a) When generating the trim mesh surface either increase the size of acceptable triangle

sizes or turn off the Delete large triangles from surface option:

b) Insert an extra section of markers that dissects the hole in the surface (this will create triangles that have edges that lie within the acceptable range).

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Grid Spacing dialog In Version 13, Maxsurf will automatically name new Sections added based on the location where the Sections have been added. For example:

Select Station 3 by clicking on the 3 number in the grey cell to the left of the row.

Click the Add button and add 3 Sections below St 3:

You will see that the Stations names are evenly numbered between station 3 and the next station 4:

Tip: To space the new stations evenly, you should

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select the all the rows over which you want the even spacing to apply click the Space button and select the From Station option:

The From station option automatically works out an even spacing between the topmost and lowest row in the selection.

Click OK to accept the spacing and click OK to close the Grid Spacing dialog

Maxsurf Menu Changes To make the Maxsurf and Workshop user interface more consistent, the following menu changes have been made:

Precision has been moved from Surfaces Display menu Preferences has been moved from View Edit menu

The Shape menu command and corresponding toolbar button that used to show/hide the entire model has been removed. To show or hide the entire model, use a right click command on the assembly tree in the Assembly Pane.

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Bug fixes and minor changes A problem where changes in the Frame of Reference dialog were sometimes not

processed if the dialog was closed by pressing the Enter key rather thank clicking on the OK button has been fixed.

A problem with the incorrect zero point being used when importing a trimesh has been fixed.

The Hydrosatics dialog will remember the last used displacement and VCG. However the VCG will be reset to 0.0m each time a new model is loaded into Maxsurf.

The Surfaces | Add Surfaces menu has been re-arranged slightly and a new standard surface which is the canoe body of a simple round-bilge yacht form has been added. If you have customised this list in previous versions, these customisations will not be migrated. You can retrieve your custom surfaces by saving them from the old version and re-adding them in the new version. For a new installation, the menu will look like this:

In the Frame of Reference, Vessel Type, Parametric Transformation, Hydromax Grounding and Waveform and similar dialogs (where there is a view of the vessel) t is now possible to resize the dialog, zoom with the mouse wheel and pan by click and dragging with the mouse wheel.

The Calculation Extents dialog now remembers the specified for and aft extents between uses.

Prevent crash when attempting to load incompatible jpg background images. If a jpg image fails to load, then try converting the image to png format

Trimming curves visibility button has been added to the end of the visibility tool bar. The button toggles the display of trimming curves (curves imported from other file formats that generate trimming regions). Turning on the display of trimming curves has previously only been available through the Contour visibility dialog box.

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The display of parametrics when trimming grey is selected now works correctly. All dialogs with a list of surfaces now have a select all and deselect all buttons

this is to aid in the management of designs with large numbers of surfaces.

Mouse rotate icon changed to 3D rotate. Untrim surfaces dialog box now has check marks next to surfaces. When

untrimming from the dialog box only the surfaces that have trimmed regions will appear. Place a tick mark next to the surfaces you want to remove trimming from.

In the surface areas dialog, the area centroids LCG, VCG, TCG have been renamed LC area etc.

Control points on bonded edges are displayed in a different colour. If the bonding is with C1 continuity, then the neighbouring control points also affected by the bonding are also shown in the same colour as those in the edge.

Trimmed bonded contours are now drawn the same colour as other bonded edges. Control Points are no longer clipped when dragging a point in rendered

perspective view

Parsing of grid spacing labels in data entry tables has been improved. A bug that in some cases meant that a trimmed away edge contour could be

selected (even though it was not drawn) has been fixed.

Visibility of bonded edges is now independent of edge visibility. Previously bonded edges could not be displayed if edge visibility was turned off, this is no longer the case.

Rhino version 4 file format is now supported for import and export. Export of IGES files format supports surface names. The performance with large models, that have several thousand control points, has

been greatly improved.

Toolbars have been added so that buttons are available for the majority of Maxsurf commands. You can either turn on these new toolbars or create you own custom toolbars using the command buttons provided.

Property Grid for surfaces now enforces a surface name length of less than 32 characters.

Trim contours are no longer selectable when trimming is turned on and edges are hidden.

In particular a new Control Point view options toolbar has been added to Maxsurf, this allows you to very quickly change the order in which the control points are displayed in the Control Points Window (Row-Column or Column-Row). Previously this could only be done through the Preferences Dialog:

Control Points table: List Control points by Row-then-Column or by Column-then-Row

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Hydromax

Fluid densities It is now possible to save and re-load the analysis fluid densities. Theses commands may be found in the File menu. The densities file may be edited manually if desired. There is one row for each of the 18 fluid types. The four columns, each separated by a tab character. These are fluid name, fluid code, relative density, colour respectively (the colour is in hexadecimal for the red, green, blue components and are probably much more easily edited in the Density dialog. The name and code for the first entry, Sea Water, cannot be changed (any changes made will be ignored). All other entries may be edited (the same restrictions area applied as when editing through the Density dialog).

Sea Water S 1.0250 6D00FF00FF00 Water Ballast B 1.0250 6D006D00FF00 Fresh Water W 1.0000 FF005F005F00 Diesel D 0.8400 FF005B00FF00 Fuel Oil F 0.9443 6D00FF006D00 Lube Oil L 0.9200 7F007F007F00 ANS Crude C 0.8883 3F003F003F00 Gasoline leaded G 0.7499 FF0000007F00 Unlead. Gas. U 0.7499 FF007F007F00 JFA J 0.8203 7F007F00FF00 MTBE M 0.7471 F600FA00C900 Gasoil GO 0.8524 FF00FF007F00 Slops SL 0.9130 FF006F00FF00 Custom 1 C1 1.0000 D6000300D600 Custom 2 C2 1.0000 D600D6000300 Custom 3 C3 1.0000 0300D600D600 Custom 4 C4 1.0000 D60003000300 Custom 5 C5 1.0000 DF00DF00DF00

If you make an error, you can always reset the densities to their default values in the Densities dialog.

Streaming the Report to Word To accommodate the option to send the report directly to Word, a new report generator engine has been implemented. Sending (or: streaming) the report directly to Word provides the user with the full editing capabilities of Word and should speed up the process of formatting and producing a stability booklet to your requirements. How does it work? When the option to Send report to Word option is selected from the Edit | Preferences menu and an analysis is run, Hydromax will automatically open a new word document and populate the document with the exactly the same analysis results as would otherwise be displayed in the Report window. Every time you run an analysis, Hydromax will append the analysis results data to bottom of the word document. Changes to Report window The Report window in Hydromax has changed only slightly: the option to split tables in the Report window has been removed. Streaming to Microsoft Word can be enabled in the Edit | Preferences dialog box. With this option selected, Hydromax will create a Microsoft Word document when output is sent to the report.

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Loadcase Window

Hydromax loadcase column order

IMPORTANT

The order of the Hydromax loadcase columns has been changed. The vertical and transverse ordinate columns have been switched. This is important for all users who use pre-made excel spreadsheets to do post processing on Hydromax results & reports.

Unit Mass Column The loadcase format has been changed to include both item and total mass columns (previously the same column had been used for the unit mass of fixed mass items and the total mass of tank items). The same has been done for free-surface moment.

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New loadcase window with additional columns and colour formatting

Tanks filling levels may also be specified by sounding. For tanks the method used to specify the volume of fluid in the tank is shown in bold (percentage full, sounding or mass).

Loadcase Sorting A number of additional tools are available for controlling the order in which items and tanks occur in the loadcase. You may move selected items and tanks up and down in the loadcase; you may also sort selected items by name, fluid type (for tanks) etc.

New loadcase commands: Insert row | Delete row | Sort rows | Move row(s) up | Move row(s) down

Sort selected columns

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After moving loads, subtotals and subsubtotals, you may have to use Analysis | Update Loadcase ( button) to update the subtotals and subsubtotals. To ensure data consistency, Hydromax does this automatically prior to running an analysis.

Loadcase Naming The loadcase name may now be changed simply from the case menu. Previously this had to be done using File | Save Loadcase as.

Subsubtotal Rows As well as subtotal rows (which add all the items above them to the previous subtotal), sub-subtotals may be inserted. Sub-sub-totals must start with the text subsubtotal. As before sub-total rows must start with the text total or subtotal.

Comment lines in Loadcases Before version 13, comment lines could be inserted into a loadcase by making the item name empty a blank line or by preceding the text with a full-stop. (In the case where a full-stop was used, this was then not displayed which caused problems when copying and pasting.) In version 13 we have changed allowed comments to be identified by using the dollar ($), apostrophe () or full-stop(.) characters but they are also displayed (to avoid problems with copy and paste. As before, a blank line is also permitted. (note that in 13b1 and 13b2, a preceding space character is also allowed to denote a comment, but this will be removed, so it is not recommended that this method be used.

Colour Formatting Colour options have also been added (View | Colour menu when Loadcase window is frontmost). Different colours can be defined for fixed mass items and tanks; alternatively, tanks may be displayed in the same colour as the fluid they contain (Analysis | Fluids dialog).

Create New Loadcases based on Template To avoid rework, an existing loadcase may be used as a template when creating a new loadcase. To do this,

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In the loadcase window, select the Loadcase you wish to use as a template

Bring the loadcase you wish to use as a template to the front for example by clicking on the tab on the bottom

select File | New

Select yes A new loadcase will appear in one of the blank () loadcase tabs. If there are no blank tabs left, you will either have to close an existing loadcase, or add more loadcases using the Case | Maxi. Number of Loadcases command.

Note The template is only used during the creation of the loadcase. Once a loadcase has been created from a template loadcase, changes made in the template are NOT automatically changed in the loadcase derived from it.

Loadcase compatibility between v12.xx and v13 In v12 loadcase comment lines could be added by making the first character a .. In v13 this has been extended so that any text that is preceded with a space now indicates that the row is a comment, not a mass. This was done because there were copy/paste issues in v12 with comments that began with a "." Thus in v13, any preceding spaces will be removed from item names in a v12 loadcase. Conversely if you have a v13 loadcase that you wish to open in v12, you should ensure that any comment lines are either completely blank or start with a . character. A comparison of the total loadcase mass between V12 and v13 is also recommended. Subsubtotals should also be avoided.

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Floodable length graph A new Bulkheads table has been added to the Data input window. Bulkheads entered here are automatically sorted by longitudinal position and in the Floodable length analysis the compartment lengths may be plotted with the floodable length curves for easy verification that the critical compartment lengths are not exceeded. These options are available in the Data | Data format dialog (when the floodable length graph is topmost). The vessel profile (centreline buttock) may also be displayed. All compartment standards up to the maximum specified will be plotted.

Floodable lengths graph options: You can fix the y-axis so that it is the same scale as the x-axis. You can choose to plot the different compartment standards up to a specified

maximum value.

You can also display the vessel profile (shown in light grey) Bulkhead locations are specified in a new table in the Input window. The graph

updates in real time as you adjust the bulkhead locations so once you have calculated the floodable lengths, you can quickly adjust the bulkhead locations so that the vessel meets the required compartment standard.

New stability criteria A number of new stability criteria have been added since the original release of v12.0 in subsequent updates to version 12 and are described in detail in these release notes. See our Maxsurf release notes webpage.

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http://www.formsys.com/support/knowledgebase/maxsurf-knowledgebase/releasenotes


Bug fixes and minor changes A problem where the Loadcase did not automatically update if the permeability of a

child tank was changed has been fixed. This bug did not affect results since a recalculation of the loadcase is forced just prior to analysis.

The "DF angle" has been renamed "Immersion angle" in Key points results table. References to Relative density have been changed to Specific gravity. To

obtain density in kg/m3 multiply the specific gravity by 1000.0 kg/m3.

The waterlines are no longer shown in profile or body plan views. A problem where the incorrect sounding was shown in the loadcase for very small

tank loadings has been fixed.

A problem where the IMO free surface moment was not recalculated at each heel angle has been fixed.

The loadcase subtotals now automatically update if items are sorted or moved previously, they only updated when an analysis was performed or the loadcase was manually updated.

MARPOL criteria: due to additional parent criteria being added, it is now possible to evaluate some MARPOL stability criteria more effectively, as such the criteria library has been updated. It is now possible to check downflooding immersion from the GZ analysis (25 3a or 28.3.1) also in these criteria the check for margin line immersion has been removed. For 25.3.b, 28.3.2 the option of extending the acceptable equilibrium heel angle if no deck edge immersion occurs is included. And for 25.3.c, 28.3.3 the range is 20deg beyond equilibrium.

A Microsoft Word template document has been added: C:\Program Files\Maxsurf\Utilities\Hydromax\WordMacros.doc. This file currently contains two useful macros for formatting the Hydromax report. The first will resize all selected pictures to the specified percentage of their original size; the second will format all selected tables to AutoFit to Contents.

When an error occurs with the evaluation of stability criteria the error messages are currently displayed in a dialog. These error messages are now also displayed in the status column of the relevant criterion (previously it would say Not Analysed). This is to aid with the distinction between criteria that were not analysed because they were not relevant to the analysis and those that could not be analysed because of an error in the criterion parameters.

Hydromax can now have different magnitude positive and negative limits for shear force and bending moments. Please note that for a file saved in 13.01 with different magnitude limits, these limits will not be correctly read into an older version of Hydromax (this only affects these limits; the rest of the model will be read correctly).

When editing stability criteria within the criteria dialog, the library file is automatically saved whenever a criterion is added or deleted this is to ensure that the library is regularly saved in case of system failure. You can also save the library from the right-click menu in the tree control.

The wording in the file open options dialog (when opening a Maxsurf design file) has been modified to clarify what Hydromax will do for each option.

A crash which sometimes occurred when calculating stability criteria whilst in longitudinal strength analysis mode has been fixed.

A problem which caused tanks with zero width to be incorrectly formed has been fixed.

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A problem which sometimes caused range of positive stability criteria with a specified heeling arm to be calculated incorrectly has been fixed. This problem only occurred if the GZ curve failed to intersect the heeling arm.

Under some conditions tanks failed to have their correct volumes displayed in the loadcase a ? symbol was shown instead. This has been fixed.

Tank calibration report now lists each tank calibration table separately with the tank calibration graph. Previously calibration tables for all tanks were listed below each graph.

A bug which allowed the Intact damage case to be deleted and edited via COM has been fixed

It is now possible to edit the current damage case without having the damage case window at the front. If the damage case window is at the front, then the damage case of the currently selected column will be edited.

In COM, the criteria error dialog has been disabled. In COM, you can copy a complete table with a single command:

Hydromax.Design.CopyTable

The number of decimal places for GZ areas has been increased. When reading in an existing Hydromax model the Include Skin Thickness

checkbox is ticked if the model sections originally included skin thickness.

You can now save the Compartment definition when the Sounding pipe table is frontmost. Just like in the previous version, the sounding pipe data is saved together with the compartment definition. This is because the two are intrinsically linked and the data cannot be separated.

Where relevant, modifications to the sounding pipe data now cause immediate updates to related cells in the Sounding pipe table previously a redraw of the table had to be forced.

The default relative density for both Sea Water and Ballast water has been changed from 1.0252 to 1.0250

The wording in the Sections Calculation Options dialog that appears when you open a file in Hydromax has been modified to make it more clear what each option does. The actual functionality of the dialog and its options has not changed.

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Workshop

Workshop Part table column order

Important The order of the Workshop Part table columns has been changed. The vertical and transverse ordinate columns have been switched.

Surface association with frames Previously in workshop a frame was formed at a section location according to the currently visible surfaces. In Workshop 13 you can choose which surfaces will be used to form the frame. To do this you need to click on the Set Frame Boundary Surfaces button in the Frame Properties dialog box. The Frame Boundary Surfaces dialog will appear and lets you select the surfaces to be used for forming the frame.

This function is particularly useful for designs that contain large numbers of surfaces.

Note The way Workshop forms frames along a section is very similar to the way that Hydromax forms hydrostatic sections. Same as in previous versions of Workshop, it is still important that the selected surfaces form one closed contour with a maximum of one opening. See the Hydromax manual on section forming for more information.

Workshop Boundary Surfaces - Video

View a video that shows how, by associating surfaces with a frame, you can remove portions of a frame such as bulwarks, skegs or superstructures.

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http://www.formsys.com/extras/FDS/webhelp/hydromax/hydromax_sections_forming.htm#Hydromax_Sections_Forminghttps://www.formsys.com/maxsurf/videos/new-in-version-13/version-13-videos/workshop-frame-boundary-surfaces#im9nE2BO2FYNo-GzR8tgiQ


Triangular Plates Workshop will now add plates on triangular surfaces (surfaces with compacted corner control points) and develop them. To do this for example on a bowcone:

A small magenta coloured dot will appear in the corner.

1. Select the point of the triangular surface using a rectangle selection Then,

2. Select the edge or contour opposite the point (#2)

3. Select the any of the adjacent edges (#3)

4. Select the edge opposite to the previous selected edge (#4)

5. Select: Plate | Add plate as you would for a normal plate

6. It is recommended to check the plate mesh

7. Calculate the Selected Plate

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Workshop Menu Changes To make the Workshop and Maxsurf user interface more consistent, the following menu change has been made:

Precision has been moved from Data Display menu

Bug fixes and minor changes The Frame that is visible in the Parts window will be recalculated when Calculate

selected Frame is selected from the Frame menu. This also applies to Decks, Plates and Stringers visible in the Parts window and the Calculate selected .

Shell expansions drawings are now calculated based on the currently visible surfaces. Before generating the shell expansion drawing, the model must be set up correctly. The shell expansion drawing is generated by calculating the girth distance around the surface of the vessel from the baseline to the part. Hence it is important that all superfluous surfaces be either set to internal use or made invisible so they are not included in the girth calculations. Surfaces normally switched off during the shell expansion calculations include the superstructure surfaces, tank boundaries, railings etc. Surfaces that are normally on include the hull surfaces, any chine surfaces and the main decks. Normally the trimming is also turned on prior to a shell expansion so that the trimmed sections of the surface are not included in the girth calculations.

Once the model is set up correctly the shell expansion drawing can be generated by choosing Calc Shell Expansion from the Plate menu.

There is now a calc all visible parts option in the data menu. This way you can calculate only the parts you are interested in by setting them to visible and all others to invisible.

There is a Save as Version 12 function in the File | Export menu. This will enable version 13 files to be opened in version 12.

A new button has been added to the visibility toolbar. The button toggles the display of plate meshes.

It is recommended to check the plate expansion calculation by viewing the plate mesh.

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Plate names can now be exported with dxf files from any of the drawing windows. A bug that was causing the stringer development to be incorrect when the

orientation was set to any angle other than normal to the surface has been fixed. Note that the development calculation does not take upstand orientation into account. This means that when a stringer has an upstand orientation that is different to the orientation of the stringer, this will not be taken into account during the development calculations.

When a stringer expansion was exported via dxf, sometimes there were duplicate points on top of one another. This may have caused problems with some cutting machines. This has been fixed.

A warning dialog box now appears to tell users that the mirror plate across centreline flag is set to true for a plate which does not have an edge on the centreline. Also a bug has been fixed that was causing an incorrect plate expansion for some mirrored plates.

Upstands will now only be displayed at the intersection of visible frames and visible stringers.

Out of memory crash, when calculating plates. Workshop now warns of the lack of memory and the need to reduce the precision.

Trim contours are no longer selectable when trimming is turned on and edges are hidden.

A crash that occurred when the delete key is pressed in Variable Web Depth Opening dialog, Radius tab (when there are no values in the table), has been fixed.

Zoom and pan are now supported while adding a stringer. A bug that was causing plate template contours to extend past the edge of the

plate to the edge of the surface has been fixed.

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Seakeeper

Roll motions of catamarans The added mass and inertia in roll for catamaran vessels is now computed from the heave properties of the vessel. This has been found to provide accurate predictions of the roll response, particularly for catamarans with wider spaced demihulls (S/L above about 0.35). In addition, Seakeeper can now measure the hull sections directly from a catamaran model provided that the Vessel Type data are defined in Maxsurf:

Maxsurf Vessel Type dialog

If a catamaran model is loaded into Seakeeper the demihull separation will be automatically read from the Vessel Type data in the file. However as before, it is still possible to change the spacing (and indeed vessel type) in the Seakeeper vessel type dialog:

Seakeeper Vessel Type dialog

This feature enables you to investigate the effect of demihull separation on seakeeping performance and also to use a monohull parent hullform as a basis for a catamaran model (this was the method used to compute catamaran seakeeping in previous version of Seakeeper). Note that these changes will only affect the computations but not the model as drawn in Seakeeper so if rendered simulations with the actual physical model are required, this model should be generated in Maxsurf and analysed without modification of the Vessel Type characteristics in Seakeeper. The roll damping factor is automatically calculated for catamarans.

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http://www.formsys.com/extras/FDS/webhelp/maxsurf/setting_the_vessel_type.htm#Setting_the_Vessel_Type


Results saving It is now possible to save and re-open Seakeeper analysis results. To save the results of an analysis choose: File | Save Seakeeper Data As and select Seakeeper analysis results as the file type. To re-open the data at a later date, first open the Maxsurf model, then choose the relevant Seakeeper analysis results file from the File | Open Seakeeper Data dialog. These files can be quite large, requiring approximately 1.5Mbytes per heading/speed/spectrum combination, depending on the number of remote locations, and frequencies analysed. Thus 5 speeds, 10 headings and 5 spectra would result in a file of about 5 10 5 1.5Mbytes = 375Mbytes.

Choose Seakeeper analysis results as the file type

Additional remote location calculations Three additional calculations have been added for Seakeeper remote locations. These are:

Subjective Magnitude (SM); MSI 2hour exposure: OHanlon and McCauley 1974 MSI specified exposure McCauley et al. 1976

These new data are given in an extra row for each remote location in the Results Summary table. The details of these calculations and how they differ from the existing MSI calculation are explained below.

Subjective Magnitude The calculation of the Subjective Magnitude follows the method described in Lloyd 1998 pages 306 to 309 and is summarised below.

43.130SM

=

gs

A&&

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where A depends on the encounter frequency, , in rad/s and is given by: e

( ){ } ( ){ }22 ln5.13ln6.496.75 65.1exp1 eeeA += ; and the vertical acceleration can be evaluated from the vertical motion spectrum: 30s&&

430 2 ms =&& , where is the 44mth spectral moment of the vertical motion spectrum at

the location of interest in m/s2; g is acceleration due to gravity;

and the average frequency of the motions can be estimated by: 2

4mm

e = Subjective magnitude is on a scale of zero to 30: 0 5 Moderate 5 10 Serious 10 15 Severe: necessary to hang on 15 20 Hazardous 20 30 Intolerable

Motion Sickness Incidence Motion sickness incidence (MSI) is the percentage of subjects who vomit in the specified time that subjects are exposed to the motions. The data were derived from test on healthy, young, males students who were subjected to vertical motions for a period of up to two hours. Thus extrapolation to other demographics or longer durations of exposure can be difficult. There are three different ways in which motion sickness incidence is calculated in Seakeeper. ISO 2631/3 1985 and BS 6841:1987 Although not strictly MSI accelerations integrated over 1/3 octave bins are plotted against acceleration limits defined by these two standards. The likely discomfort can be gauged by how close these acceleration curves approach the defined acceleration limits. MSI after 2 hours exposure The motion sickness incidence derived from the formulation original 1974 paper of OHanlon and McCauley is calculated for a fixed exposure time of 2 hours. Seakeeper evaluates the MSI using the method described in Lloyd 1998, pages 304 to 306. The MSI is given by Lloyd as:

=4.0

log100MSI%

MSI3

gs

&&

where is the cumulative normal

distribution function up to x for a normal distribution with zero mean and unity standard deviation. (see Excel function NORMDIST(x, 0, 1, TRUE).

)(x

Lloyd gives the factor ( )2MSI log32.2819.0 e += with e in radians/s this is almost the same as the original equation of OHanlon and McCauley:

( ) ( )2MSI log32.2log697.3654.0 ee ff ++= with in Hz, noting that ef ee f 2 = . Seakeeper uses the latter. The same frequency as that used in the SM calculations is

used, namely: 2

4mm

e = and the acceleration, 3s&& , is given by 43 798.0 ms =&&

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MSI after specified exposure McCauley et al. 1976 reanalysed the original OHanlon and McCauley 1974 data and presented a formulation whereby the exposure time could be accounted for. This method is also computed by Seakeeper and is the only place where the MSI exposure time for the remote location is used. The exposure time can be specified for each remote location (you can define multiple remote locations at the same point on the vessel and give them different exposure times if you wish).

Specification of exposure time for each remote location for the MSI 1976 calculation

The procedure described by Colwel 1994 is used with the frequency and acceleration values given by Lloyd for the 2 hour MSI, above.

( ) ( )'100MSI% ta zz= ; where ; 851.1)(log809.5)(log277.9)(log128.2 2 = eea ffazand ; 904.2)(log989.1134.1' += tzz at

with the acceleration, in g, given by 43 798.0 m

ggs

a ==&&

.

Effect of exposure time on MSI 1976: frequency of motion 0.1Hz

The effect of exposure time on MSI can be seen in the figure above. When the exposure is longer than about two hours, there is relatively little increase in MSI, this is especially true at higher accelerations, i.e. all those victims that are going to vomit have already done so within two hours. As the acceleration decreases, the exposure time required to achieve near-maximum MSI decreases slightly. The frequency of the acceleration in this case was 0.1 Hz which is near the worst case.

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Comparison of MSI predicted by 1974 and 1976 methods: exposure 2hrs; frequency of motion 0.107Hz

The effect of acceleration on MSI is shown for an exposure period of two hours in the figure above. It can be seen that both formulations give very similar results. The frequency of the acceleration in this case was 0.107 Hz.

MSI Results As before the comparison with the ISO and BSI curves are given in the MSI table and graph respectively.

Existing comparison of accelerations compared with ISO and BS standards

The SM and MSI for 2 hours exposure and the specified exposure time are presented in the Summary results table. The last row for each remote location gives the SM in the second column, then MSI for 2 hours exposure using the OHanlon and McCauley 1974 method in the fourth column and in the MSI for the specified exposure period is given in the sixth column. These data may also be plotted in the Polar Graph window.

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Additional SM and MSI results for each remote location

References Colwel, J.L. Motion sickness habituation in the naval environment. Defence Research Establishment Atlantic Technical Memorandum 94/211. Canada. May 1994. Colwel, J.L. Human factors in the naval environment: a review of motion sickness and biodynamic problems. Defence Research Establishment Atlantic Technical Memorandum 89/220. Canada.

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