INTRODUCTION TO LINEAR STATIC ANALYSIS USING

MSC.PATRAN/NASTRAN

Goal

The goal of this exercise is to set-up a simple linear static analysis of a square plate using shell

elements. The plate is fixed on two edges and subjected to a point force. Simulation results

(displacements) are shown.

Exercise outline

Model setup

Model definition

Geometry

Mesh

Boundary conditions (BCs)

Material properties

Loadcase

Analysis

Results evaluation

Model setup

Create new working folder.

Create new file, change its name and extension to *.db

Double click to open the file in default program - Patran.

In Patran choose new file

choose previously created file

confirm creating new file message

choose model preferences

change default model units to millimeters

Model definition

Model geometry

Open geometry modeller

Create points for subsequent plate definition

Add four points [0 0 0], [0 100 0], [100 100 0], [100 0 0]

Then, create two curves

Using created previously curves define a surface

You can change display mode by using various options from the bar at the top of the screen

Lighting can be managed by through Light sources menu

Select all light sources and apply

Mesh definition

Once the geometry has been created, proceed to mesh definition

Use automatic ISO mesher to create unifrom mesh with element edge size of 10 mm

The model should now look like this

Boundary conditions

Open Loads/BCs menu

Define new boundary condition - fix nodes at two edges of the plate. Specify BC's name, ...

... constraints (DOFs), ...

... and application region

apply changes

The model should look like this

Prescribe a force at selected node

Change BC type to force

Specify desired force magnitude and apply

Select application region, apply

The model should now look like this

Material properties

Open material definition menu

Specify material's name

and its properties

Save changes by clicking apply

Open properties menu from the bar at the top of the screen, specify name

Select "Input properties", and choose alreade defined material by clicking material button

choose defined material

specify plate thickness

Specify application region

select all the elements and apply

Loadcase definition

Apply specified loads to create a loadcase. Open loadcase menu, select Action: Modify

Select default Loadcase

check if both previously defined boundary conditions are selected

Confirm by clicking apply

Analysis

proceed to analysis menu

switch analysis method to "analysis deck", this will create solver input file, but will not submit it to the

solver

Check it the solution type is set to static analysis and apply

Find the BDF file in your working folder

Open file in notepad, try to recognize entries in BFD file.

Run Nastran

Browse BDF model file

Run the analysis

After Nastran finishes, check if *.xdb result file has been created

Result evaluation

In Analysis menu, find "Access Results" option

Select results file and apply

Go to Results menu

Check results you want to display

You can change display settings, e.g. turn off undeformed model configuration

and geometry in Plot/Erase menu

Simulation results should now look like this