I have yet to find any information regarding Inventor Nastran's ability to mesh using Hex 8 (linear six sided) or Hex 20 (quadratic six-sided) elements. Is this a feature that I'm missing? Most commercial software packages have hex elements included in the mesh generation. I guess this is to say, hex element is to tet element and quad element is to tri element, and it would be great to have hex elements in the program.  Show More

Bring back the FEMAP tutorial manual and expand with additional non-linear, dynamic and contact examples. Show More

 Hello!   I would like to suggest that the User Manual be updated.  In particular, there are no sample problems (and no ".nas" files for linear prestress transient, linear prestress frequency response, linear prestress complex eigenvalue, or prestress random response (which is really just calling a random post processing of the prestress freq response run).   Without some guidance on how to set up these very useful solution types, they may as well not be there.  The FEMAP translator doesn't support them, so there's no opportunity to study the data deck (".nas") that it's exporting.   For example, I've learned that it's necessary to import a prestress modal to get these solutions to run.  That's ok, but there's no clue in the User Manual that this is what has to be done.  It sure would be helpful - and a huge time saver - to have a couple of sample problems presented along with the .nas file and the correct results. I'm sure that the development team has run many sample problems - let's get them in the book!!   The utility of the program would be significantly enhanced in general if more example problems for all solution types could be added to the User Manual.  Perhaps I'm behind the power curve compared to most users, but I spend way too much time getting a .nas to run for some of the options and solution types...and then more time to verify that the results the file are producing are correct.   More example problems that represent common cases would cut the time dramatically.   A related point is that FEMAP hasn't added to the translator for Autodesk Nastran solution types since long before Autodesk acquired the program.  For some of us that consult, InCAD is just not a viable solution.  May I request that Autodesk consider getting with the FEMAP team at Siemens  to add support to the translator for the solution types that are currently not supported?   FEMAP provides support for their NX Nastran solutions that aren't covered in the translator but they don't support Autodesk Nastran.    HELP!  As a consultant, I'm not profitable/competitive when I have to work out stuff that should be documented.  We're competing with MSC Nastran and NX Nastran as well as Ansys and Abaqus... and all of them seem to have stronger documentation.   It's all about getting the job done correctly AND - critically -  timely!    Thanks for considering this request.   Best,   Andrew Show More

I mentioned this in the general forum but I think it belongs here.   Currently, if you need to specify a non-linear elasto-plastic stress-strain curve in Nastran, you have the MATS1 and MATS2 formats available.  Neither of these is very convenient if you have tensile test data available.  MATS1 works for a bilinear stress-strain model, but if one is interested in the behavior close to the yield point, or if the region between the linear parts of the bilinear model is large, a bi-linear model that intersects at the initial yield point may not be  appropriate.  Moreover, when entering points into TABLES1, the MATS1 convention dictates that the first point must be the origin and the second point must be the point of initial yield.   Most of the time, it doesn't really matter... but it's also not strictly correct.  Initial yield is generally defined in terms of a strain offset.  A straight line from the origin to the yield point is at the secant slope, but that's not the Young's modulus slope.  Yes, it's a  nit-pick in most cases, but still... why not make it correct?   MATS2 enables one to enter the Ramberg coefficients.   This is good, but it seems circuitous and unnecessary to have to compute the Ramberg coefficients to approximate a tensile test curve if one is looking at the actual tensile test curve.   My suggestion is that a format (MATS3 perhaps?) be defined that allows direct input of points pulled off the stress-strain curve, along with the method of determining yield point  such as 0.1% offset, 0.2% ofset. 0.5% extension under load, etc. ,   I'm pretty sure that Ansys has exactly this; so should we.  It would save time.    It's rare that tensile test data actually identifies the onset of plastic deformation, but in case one does have that information, one should be able to put in on the 'MATS3' stateemnt directly.   An even better feature would be the ability to put in curve points and yield criteria from tensile test curves in all three axes into TABLESi.  Orthotropic properties are very important!  I don't think Ansys has this.   It would also be very nice to be able to put in some detail about lateral strain, which can easily be obtained with a micrometer during a tensile test, and have Nastran compute Poisson's.  I recommend that this data not be required at every point.  The user should be able to put in whatever he has, and Nastran can interpolate.  Poisson's shouldn't change much in most cases.      The Nastran output should be able to give some useful material data that it can calculate from the curve(s), such as Young's modulus, proportional limit, yield point computed based on 0.1% offset, 0.2% offset and 0.5% extension under load, Poissons perhaps, etc. A lot of this might not have anything to do with the current analysis, but it would be useful for the analyst to have.   Show More

Hello everyone,   Any chance of adding support for NVIDIA CUDA cores or OpenCL, to enhance the solution processes?   Other solvers (e.g. ANSYS, MSC.NASTRAN) support them, and other Autodesk products also include support for them...   Thanks! Show More

It would be extremely helpful if a joint between two irregular meshes with common edge geometry in a FEMAP model could be glued or welded together. This would help keep element size down and help reduce model setup time. Show More

Hello,   Would it be possible to update the frequency response analysis modules in Autodesk Nastran to output corner stresses?  I think it is strange that this is not included for these modules while other analysis modules do output corner stresses.     I appreciate all that the Nastran team does!     Thank you, Bryce Fox Mechanical Engineer Custom Microwave Inc.  fox@custommicrowave.com     Show More

It would be nice if when a model is running, if other files are opened and added to the queue during the run, that they would then also be run.  I just lost 10 hours of solve time because I added models to the queue of a model that was already running, and they did not run over night.  Also, on several occasions, I have had a queue not continue because after the first model in the queue is finished solving, a message box pops up and asks if I want to load the FNO file, and the solve pauses.  As I am not there and was planning for several models in the queue to run overnight, I again have lost solve time and been delayed effectively a day of work. Show More

Please add aeroelastic capability. Show More

To help separate shear deformation in e.g. sandwich core selection it would be useful to have a result vector for shear deformation only (similar to the standard T1/T2/T3 translation vectors which show total translation). Show More