Best vibration+noise FEA
Best vibration+noise FEA
(OP)
what is the best vibration FEA solver, for problems related to sound and noise?
I mean modal and forced vibrational analysis with an eye on acoustics.
An integration between vibration and sound would be great! What software can does this nowadays?
Material description should be as accurate as possible (I am thinking of complex materials like resin+fibers, foams, composites, etc.)
I mean modal and forced vibrational analysis with an eye on acoustics.
An integration between vibration and sound would be great! What software can does this nowadays?
Material description should be as accurate as possible (I am thinking of complex materials like resin+fibers, foams, composites, etc.)





RE: Best vibration+noise FEA
BJP
RE: Best vibration+noise FEA
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RE: Best vibration+noise FEA
I have the possibility to measure acoustically, so that would be the final validation of FEA efforts. Therefore a feature I would consider is the possibility to integrate the vibrational analysis into an acoustical analysis.
GUI, features for speeding up the analysis, and price are important, but I would give a lower importance to them now.
RE: Best vibration+noise FEA
Most, if not all, commercial codes will give you "reliable" results. This is a topic that has been discussed previously (the definition of "best" results or "better" software), and is difficult to quantify. In the end, most codes will do the job for you, but it's down to the experience of the user whether or not the answers are garbage or useful.
For me, I've been using ANSYS and ABAQUS for many years, as well as a few other lesser known codes (NASTRAN, PAFEC, DIANA, NISA...). For a budget package which will do a job for you, I would consider looking at NISA, although this is quite an old code and has been lacking in development somewhat. If you have complex geometry, NISA has a limited geometry integration capability, so this is something to think about. It does however, have a brilliant eigenvalue solver, probably the best I've used along with NASTRAN. ANSYS is also excellent. With this you have very good functionality (forced vibration, acoustics, emag, statics, transient, coupled-field, &c.), an excellent GUI and excellent CAD integration. The flexibilty of using ANSYS programming language as well (APDL) is also very useful. I'm a big ANSYS fan, and I've been using it many years, so there maybe a *bit* of bias in there as you can tell. Drawback of ANSYS, NASTRAN, ABAQUS is the licence cost. If you want a purely dynamics solver for your work, it may be worth paying the extra for NASTRAN. Otherwise, have a look into ANSYS. You can check ANSYS capabilitites here http://
The above is of course non-exhaustive, and only a fragment of the info available. A good idea might be to demo a couple on your shortlist for a month each - this is very popular nowadays and is encouraged by the suppliers.
Best of luck,
-- drej --
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RE: Best vibration+noise FEA
thanks for your comment, LMS looks good...
do you know if it also imports from NEiNastran?
RE: Best vibration+noise FEA
drej,
do you know if describing mechanical properties varying with frequency leads to more accurate results for some applications?
I was showed MSC Nastran, where there is the such possibility of material properties description. I thought that if they keep this description possibility open, it should be relevant for some applications. Unfortunately they are not giving me a demo.
For example Cosmosm does not have this material properties description feature. Only has creep. But they give out demos!
RE: Best vibration+noise FEA
You can easily set the damping characteristics as a function of frequency "perfectly legally" (as a material property) within ANSYS and ABAQUS (don't know about COSMOS) and probably NASTRAN. These would be the Rayleigh damping constants (alpha/beta damping) and the material damping, but that's about it.
Of course, the above three codes also have all of the common material models (elasto/visco/plastic/etc.) such as creep you mention as well as the capability of user materials/compound (hybrid) models and composites. ANSYS especially covers the use of composites very well in the current V9, but again not sure about the other two.
Cheers,
-- drej --
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RE: Best vibration+noise FEA
It's not rocket science, but it is certainly more complex than using one package for everything.
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
RE: Best vibration+noise FEA
if I understood right from your post, you are assuming that it is relevant to use frequency dependant properties. I would like to know for what applications!
And you are saying that you are using a software tool that "learns" that frequency dependance (and other dependancies) from measured data? That would be exactly what I'm looking for!
Cheers
RE: Best vibration+noise FEA
Not sure how well NEiNastan works with Sysnoise but I assume it is the same as MSCNastran. All you need is to export out a punch file or an op2. The question I would ask is how good is NEiNastran's dynamic solver? I know MSCNastran is very good up to a certain frequency. I have more trouble after about 2 Khz where the modes become more complex and is harder to correlate. The other thing is can NEiNastran use acceleration test data directly?
BJP
RE: Best vibration+noise FEA
RE: Best vibration+noise FEA
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
RE: Best vibration+noise FEA
RE: Best vibration+noise FEA
i wish people would stop asking for the "best" software (for just about anything). there is no universal "best". even "good" software depends on so many variables.
in my humble opinion, a more sensible question would be to ask people to recommend a FEA (or whatever) package. better would be something like "i'm thinking (there's a good clue) about buying FEA package "XYZ" ... how robust is this ? what sort of problems might i find ?" why do i think this is better ... it shows you've taken the time to research the question a little (i mean, how difficult is it to yahoo or google ?)
thank you, and good night
RE: Best vibration+noise FEA
RE: Best vibration+noise FEA
Tis also one of my pet hates, so you can imagine when this came up thread727-123750 I was like a coiled spring!
Cheers,
-- drej --
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RE: Best vibration+noise FEA
It is a fully capable BEM code that has a direct interface to NEiNastran and FEMAP. It is a fraction of the cost of Sysnoise.
RE: Best vibration+noise FEA
Vibration: ANSYS/Nastran
Acoustics: LMS Sysnoise (This has been proven and tested for several years and is the most widely used acoustic software in the world).
Expensive: Yes!
But my philosophy is you get what you pay for!
RE: Best vibration+noise FEA
I have used these elements and it's very easy but I am not an acoustics expert so I don't know what their real limitations are. You would have to take a look at the abaqus.com web site to get a datasheet.