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NX NASTRAN bulk data format

NX NASTRAN bulk data format

NX NASTRAN bulk data format


I'm trying to understand why NX.NASTRAN makes an exception of allowing an integer in the field which only accepts real numbers?

As an example, I've been fiddling around with the 'instest.dat' test file that comes along with the nastran deliverable (located at: X:\Program Files\Siemens\FEMAPv1200\nastran\nxn12p02\nast). If all the X,Y and Z co-ordinates of the GRID entries are converted to integers the model still runs without FATAL'ing out. This is surprising to me as other flavors of NASTRAN which I'm very familiar with would not allow this. The complete f06 with the unsorted and sorted bulk data echo is attached to this post. (See attached: instest.f06)

Can someone explain this or am I missing something very obvious and particular to NX.NASTRAN?

I'm using NX.NASTRAN v12.2 on windows 10 64-bit OS.


RE: NX NASTRAN bulk data format

I don't know much about NX, but even the more recent versions of MSC Nastran (since 2013, I believe) add a subroutine that converts these integers to reals before running as a "convenience". Personally, I always shut this functionality off in MSC Nastran by adding the keyword 'ifpstar=no', don't know if you can do something similar in NX.

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