Introduction to Actran Release 13 Release Highlights

Jonathan Jacqmot

30 October 2012

A quick introduction to the Actran software

Actran R13.0 Release Highlights

Actran R13.0 Requirements

Summary

Agenda

The Actran Software Suite

Actran Vibro-Acoustics Actran Aero-Acoustics Actran TM

Actran Acoustics

Actran DGM

Actr

an V

I

Actran for Nastran

FE domain

IE domain Acoustic FEM/IFEM approach

Multi-purpose toolbox: several computational sequences

Direct Frequency Response

Modal Frequency Response for interior problems

Hybrid Modal-Physical Response the best of both worlds

Modal Extraction for undamped structure or cavity

+ Compressible Flow potential flow solver

+ Frequency response using a time domain LEE Solver = Actran DGM

+ Transient solver

Linux or Windows platforms

Direct & iterative solvers, multiple load & restart

Several types of parallelism available

Actran Solver

Improved Physics

Rigid body elements

Porous Miki model

Boundary Conditions

BC_MESH Integration method

Actran DGM: Velocity BC

Actran DGM: Thompson BC

Actran DGM: Transfer admittance

Perfectly Matched Layers

Analysis Schemes

Combination of modal/physic approach and staggered solver

Inputs/Outputs

Selection of output requests

Specification of tolerance lists

Specification of storage nodes for modal components

Handling of names for all components, materials, tables,

High Performance Computing

Parallelism for Aero-Acoustic computations

Reduction of parallel NFF databases

Actran DGM: performance improvements

1st level Multi-parallelism

What is New in R13.0 in a Nutshell

Ease of Use

Minimal number of elements per wavelength are

indicated during the computation

Thickness of a composite can be retrieved

automatically

NAS2ACT utility

RADACT supports multiple loadcase

computations

Support of a global damping in a composite

material

ICFD: supersonic flows regularizations

ICFD: Make CFD periodic in space

ICFD: Symmetry of flow fields

Actran VI

Reading comments from external formats

Reading comments from NFF databases,

including the mode orders,

Picking nodes is now enabled, allowing to create

storage nodes, measuring distances or to

interpret results in the PLTViewer

Validating an Actran analysis in Actran VI

Inertias of beams can now be visualized

Automatic detection of modal basis parameters

Visualization of boundary conditions

Description:

Alternative/complement to infinite elements for the

radiation in free field

Extra-layer of finite elements used to

progressively damp the acoustic wave non-

reflecting boundary condition

Application: Larger models and higher

frequencies

Benefits: Lower CPU requirements

Remarks:

SPL available in far field thanks to fully automated

FWH solver

Infinite elements should be preferred for low

frequencies analysis

Not compatible with convected wave analysis

Perfectly Matched Layers (PML)

Description: Model rigid structural or

acoustical connections

Equivalent to Nastrans RBE2

elements for structural connections

Applicable to fluid

Selective degrees of freedom

connections

Benefit: Improve the accuracy of

complex vibro-acoustic models

Applications:

Rigid connections between different

parts

Distributed punctual loads

Selective transmission of motion

Rigid Body Elements

BEGIN COMPONENT 1

RIGID_BODY

DOMAIN rigid_body_element

DOF_TO_LINK IMMMMMM

END COMPONENT 1

Description:

Semi-empirical model

Only the flow resistivity required

Benefit: More accurate representation

than Delany-Bazley model

Comparison of the formulations on impedance tube test

Miki Porous Model

Porous

Rigid support

Low density foam Plastic foam (rigid) High density foam

BEGIN COMPONENT 1

MIKI_POROUS

MATERIAL 1

DOMAIN Porous_domain

END COMPONENT 1

Description:

Model real-world microphones sensitive to the frequency and

the directivity of the acoustic field (mic. dimensions, electrical

and mechanical impedance,)

Directive microphones available as a complement to

conventional ideal field points

Benefit: Improve the fidelity of the numerical models

In practice: The pressure field computed at the field point will be corrected according to the directivity of the micro &

the incidence angle of the acoustic wave

Directive Microphones

refV

0

90

180

Ref. direction [x,y,z]

refV

)p(f).c(f)(fpc ,,

BEGIN MICROPHONE 2

MICROPHONE_FRF TXT frf.txt

MICROPHONE_DIRECTIVITY TXT directivity.txt

REFERENCE_DIRECTION 0. 0. 1.

1

20000 0.5 0.0 0.0

END MICROPHONE 2

Description: As for aero-acoustic sources, Actran can use the integration

method for mapping the vibration levels for a radiation analysis

Application: Radiation of any vibrating structure such as a gearbox or a

powertrain

BC Mesh Integration Method 1

Acoustic nodes (coarse) Possible loss

of information

Linear interpolation from the structure mesh to the acoustic nodes

structure mesh (fine)

Standard sampling

structure nodes (fine)

acoustic nodes (coarse) All information is conserved

in the process !

Integration

mapping

Benefits: coarser acoustic meshes can be used

Computation time reduced and resource saved

Higher frequencies can be reached

BC Mesh Integration Method 2

In practice: use keyword

METHOD INTEGRATION

BEGIN BC_MESH 1

NFF structure.nff

SURFACE 1

TOLERANCE_LIST 1

BC_FILE structure.nff

BC_FORMAT NFF

DISPLACEMENT

METHOD INTEGRATION

END BC_MESH 1

NEW

INTEGRATION

METHOD

STANDARD

SAMPLING

METHOD

Description: a translator can be directly accessed from Actran VI

Most relevant Nastran cards for vibro-acoustics are supported and interpreted:

Most shells, solids, fluids including infinite fluids

RBE2, CBUSH, CELAS, CONM2,

FREQ, FORCE, SPC1,

Element depending information in Nastran cards are translated into FIELDs

Compression of PIDs can be automated

Equivalent Nastran input file is created for comparing the equivalence of the Actran case

Benefits:

Create Actran vibro-acoustic model easier and faster. Easier and faster creation of Actran vibro-

acoustic model

Improve/update the translated model with Actran features (visco-thermal elements, porous

elements, )

Nastran to Actran Translator

Nastran

input file

Equivalent Nastran

input file

Actran Input

FIELDs containing:

Element orientation

Offsets

Benefit: Increase the clarity of imported meshing data

Description:

Comments provided in Bulk Data Files can now be interpreted from:

Ansa

Patran

And others

Actran comments are now also stored in the NFF result database to

ease the display of results

Actran VI: Management of Comments

Node picking selection has been improved to:

1. Create 0D entities directly into the mesh

2. Access FRF results from an imported map

3. Measure distances and/or angles between different nodes

Actran VI: Node Picking Enhancements

1 2

3

Description: visualize the following imposed conditions for any

structure node

displacement

rotation

point load

point moment

Benefit: Better control of the application of boundary conditions within

Actran VI

Actran VI: Visualize Boundary Conditions

Description & benefit: Simulation results can be heard directly from

PltViewer using your favorite audio player!

In practice:

1. right-click on any point fluid pressure result and select Convert to audio

2. A .wav file will also be generated

PltViewer: Listen to your Simulation Results

Ease of use

Performance

Multiple new capabilities

Key Highlights

Perfectly Matched Layers (PML)

Rigid Body Elements

Integration Method for Radiation Analysis

Nastran To Actran translator

Actran VI improved look and feel

Please download and enjoy Actran 13 !

Summary

Thank you for your attention!