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Explicit DynamicsR16.0 Update

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Performance• MPI Support – including MSCluster

• Large Model Initialization Speedup

Features & Enhancements• Mesh/Named Selections for Nodal Force and Nodal displacement

• Improved Handling of Remote Points

• Body-Grounded Springs

• Bulk Viscosity for Shell Elements

Explicit Dynamics 16.0 Update- Summary

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• AUTODYN now supports 3 different types of MPI

1. Platform mpi, shortened to pcmpi

2. Intel mpi (intelmpi)

3. Microsoft mpi (msmpi)

– Includes MSCluster support – log in to the headnode

• Available for Standalone Autodyn

– Explicit Dynamics Analysis and Autodyn Component Systems (in Workbench) – beta status

– Documentation available upon request

Explicit Performance- MPI Support

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• Model initialization has been improved, especially effective for large models

– Example model with:

• 4.3 million elements

• 1.6 million nodes

• 3.3 million faces

• 7 thousand bonded faces

• 400 thousand bonded nodes

– It took 5 hrs and 3 min before model starts cycling (R15.0)

– Now starts in 5 min 55 sec to start cycling (R16.0)

• So, some 50 times speedup (of initialization)

Explicit Performance- Large Model Initialization Speedup

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Mesh/Named Selections- Nodal Force and Nodal Displacement

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1. Using the worksheet

2. Selecting nodes via Mesh Selection Tool

Mesh/Named Selections- Nodal Force and Nodal Displacement (cont’d)

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• Better Remote Displacement, example:

– Ball hits underside of plate

– Plate has three holes, each fixed in terms of translation

– Remote Point translations corrected in R16.0

R15.0 R16.0

(rotations and erroneous translations) (note rotations are still free)

Improved Handling Of Remote Points- Remote Translations

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• Better Initial Conditions on Remote Points

– R15.0: Initial conditions on Remote Points would possibly not be taken into account properly when applying for example an Initial Velocity on a Rigid Body/Remote Point combination

– R16.0: A Remote Point can now properly connect a Rigid Body with other flexible or rigid nodes in a model

Improved Handling Of Remote Points- Initial Conditions

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• Allows for easy definition of a longitudinal grounded spring attached to a body

– Can be transferred to Autodynas required

• All options similar to a regular spring, except the grounded side is automatic

– Velocity controlled damper option

– Scoping options

– Pinball region

Body-Grounded Springs

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Example of incorrect behavior of shells after long elapsed times – especially in a “quasi-static” state

Bulk Viscosity For Shell Elements

fixed supportpressure applied to shell

velocity ~ 0.2 m/s

Stable results with Bulk Viscosity

• Bulk viscosity implementation for shells

– Computed per layer

– Structured shell meshes: global setting in Component system (Controls -> Damping)

– Unstructured shell meshes: per part (Component system), global setting in Explicit STR

– Furthermore see documentation