Hello,
I'm using FEMAP 11.1 with NX Nastran for frequency response and random response analyses. Following tutorials I'm using the restart capability performing first a modal analysis then the frequency response (modal frequency method) using the saved database from the modal analysis. The...
Hello,
I'm performing a random response analysis with FEMAP 11.1 and NX Nastran on a model with a very high number of modes (about 850 from 0 to 2000 Hz). The PSD spectrum is in 20-2000 Hz range. The modal frequency method gives me a result with a modal critical damping of .03, although I had to...
thread825-258197
Hello,
I'm performing a SRS analysis with FEMAP 11.1 and NXN 9.0. I'm following the FEMAP tutorial no.19 doing a modal analysis applying a SRS (acceleration vs. frequency)on a node with a large mass and a SUPORT entry in the excited DOF.
My question is: is it mandatory to use a...
Dear NX.Nastran/FEMAP users,
I have to perform a SRS analysis, applying a SRS load as follows to an assembly model:
500 Hz -> 500 g
3000 Hz -> 2000 g
10000 Hz -> 2000 g
I have never done that: how do I apply this load to my model? Is there any tutorial or example available?
Thanks
Marco
Dear Nastran/FEMAP users,
I have to perform a SRS analysis, applying a SRS load as follows to an assembly model:
500 Hz -> 500 g
3000 Hz -> 2000 g
10000 Hz -> 2000 g
I have never done that: how do I apply this load to my model? Is there any tutorial or example available?
Thanks
Marco
Hello everyone. I'm working on this problem: I have to verify the good choice of a filtering/venting PTFE membrane with a porosity 0.2 micrometers. It's applied on a closed box that undergoes a thermal vacuum test inside a vacuum chamber, with a pressure change rate of 200 mbar/min, and it is...
Hello,
I have a requirement for a max leak rate with He in a pressure vessel (1e-4 mbar*l/s). I want to test it with pressure decay method, but using Nitrogen instead of He. What is the correct calculation of leak rate using Nitrogen, and the translation in max pressure decay (mbar/s)? The...
Hello everyone,
could anyone plase tell me what is the correct procedure to perform a structural analysis by FEA on an item subjucted to random vibration? I work in aerospace field and use NX.Nastran with Femap. I know the input PSD for this item and I would like to verify its strength. It...
Hello,
in my company we have designed and manufactured a stainless steel vacuum chamber needed to perform a vibration test of an item under vacuum conditions. When performing random vibrations at full level, after some time, the weld on the chamber base broke on 180° circumference. What can I...
Hello,
I have to manufacture a part in Ti6Al4V due to stiffness reasons, for a space application. Our customer told us that, due to poor resistance of this material to fretting and wear, we'd better apply a surface treatment. The suggested alternatives are anodic oxidation as per SAE AMS 2488D...
Hello,
I have to perform a verification of a glued connection between titanium and bronze parts. The available glue data are tensile, shear (wrt temperature), compressive and flexural strength. I have a bronze bellows with 8 bar pressure inside glued on a titanium structure, then I have to...
Hello,
I'm looking for someone expert in random response analysis for help, since Nastran
and Femap guides are not very explicative. I try to list some doubts:
-I apply an acceleration load on 4 nodes with a PSD input (in g^2/Hz) with a model
in SI units. When I ask as output acceleration I...
Hello,
I'm looking for someone expert in random response analysis for help, since Nastran
and Femap guides are not very explicative. I try to list some doubts:
-I apply an acceleration load on 4 nodes with a PSD input (in g^2/Hz) with a model
in SI units. When I ask as output acceleration I...
