Tips & Tricks

How does VA One SEA calculate the power from TBL?

In the calculation of the power input, the calculated or user-defined pressure is the band-integrated mean-square pressure, whilst the other TBL parameters, decay coefficients, convection wavenumbers, free flow velocity etc., are used to calculate the narrowband spatial correlation function which is used in determining the joint acceptance

Extending the FMM kD range

This is currently (VA One 2009) limited by the software. Two possible options (that we could consider for the future)...

FE area junction incomplete/ broken? What can be done ?

The problem is most likely due to the FE acoustic mesh having finer/higher mesh density than the structural FE mesh.

How do I create an SEA cavity using shrinkwrap?

Procedure to shrinkwrap geometry ...

Options for computing mass local properties in VA One 2013

The ways to compute local mass properties are ...

What is the Sturm sequence?

It provides a quick way to calculate the number of local modes in an FE subsystem without performing a detailed Eigen solution (which is much costlier).

Difference in performance and requirements when solving in the GUI vs. in batch

Is there a difference in performance and requirements when solving in the GUI vs. in batch? Yes, there is a difference in how data is saved in the solve process.

Applying anechoic termination to a muffler tailpipe modeled with FE acoustics

To apply an anechoic termination, disconnect the SIF from the FE Face, then go to ...

Introduce a reflection coefficient on an infinite plane in VA One

How can I introduce a reflection coefficient on an infinite plane in VA One? One workaround is to use the following approximate procedure.

I'm trying to override properties for a fuselage section, but it’s hard to get TL to match - can you give advice?

In a pure SEA model, overriding modal density and radiation efficiency (i.e. CLF) normally gives good correlation to a hybrid model. For the resonant path, if the CLF, MIB and DLF are the same, one would expect the same answer. If not, discrepancies may come from the non-resonant path which do not get overridden by the manipulations above.