Solver for Mystran

[johnwang]

Still I am not able to get any deformation from the pload entries in that plate file.

Change LOAD = 11, re-run.

When check result, Change Slider Max to 10000.

[bernd]

Still I am not able to get any deformation from the pload entries in that plate file.

Change LOAD = 11, re-run.

When check result, Change Slider Max to 10000.

YEAH ... I tried to input the load case lines (load) int the subcase but I did not try to directly input the pload4 id. It will take some time to get into all this ...


bernd

[bernd]

...
Here's a pretty good online NX nastran documentation.
http://www2.me.rochester.edu/courses/ME ... 6:id507676
...

very helpful ...

[aerospaceweeb]

PLOAD cards are a bit harder to understand in my opinion if you're learning your way around the nastran data file.

FORCE cards are super easy for these kinds of demo problems, because, in general, writing code to distribute the force nodally is quite easy.

Also, with how mystran works, an easy way to apply forces to nodes is to just make one line of a FORCE card for each node. super easy to do in a spreadsheet, which is what us boring types do when we don't want to code.

Code: Select all

FORCE,1,101,0,100.0,0.0,0.0,1.0
FORCE,1,102,0,100.0,0.0,0.0,1.0
FORCE,1,103,0,100.0,0.0,0.0,1.0
FORCE,1,104,0,100.0,0.0,0.0,1.0
FORCE,1,105,0,100.0,0.0,0.0,1.0
...

[bernd]

attached some file ... Mystran says

Code: Select all

 *ERROR  1820: THERE MUST BE AT LEAST 1 ELEMENT IN THE BULK DATA. HOWEVER, NELE =        0

But there are a lot elements. It seams I am missing something ...

FEMMeshGmsh.bdf.txt

(79.83 KiB) Downloaded 45 times

FEMMeshGmsh.py

(99.58 KiB) Downloaded 45 times

[fandaL]

Official Mystran 12.1 documentation
https://www.mystran.com/forums/showthread.php?tid=39
does not know CTRIA6. There are only CTRIA3 and CQUAD4 (and CTRIA3K and CQUAD4K for thin variants without transverse shear deformation).

[bernd]

Official Mystran 12.1 documentation
https://www.mystran.com/forums/showthread.php?tid=39
does not know CTRIA6. There are only CTRIA3 and CQUAD4 (and CTRIA3K and CQUAD4K for thin variants without transverse shear deformation).

Thanks for the hint. I found it too. cheers bernd

[bernd]

Again problems ... I tried solid mesh ... but Mystran returned a lot of these for the Calculix cantilever example ...

Code: Select all

 *ERROR  1928: ELEMENT      149, TYPE TETRA10 , HAS JACOBIAN LESS THAN OR EQUAL TO ZERO ( = -7.3E+08). BAD GEOMETRY

Box_Mesh.py

(18.33 KiB) Downloaded 45 times

Box_Mesh.bdf.txt

(21.74 KiB) Downloaded 49 times

[johnwang]

For grid, if you use fixed form, it is 8 digits. If long form, it starts with GRID*

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$-------ID------CP------X1------X2------X3------CD------PS------9-------+-------
GRID    1               0.00E+0030.000000.00E+00         

Yours:                       
GRID           1           8000.   1000.      0.

For 10 node TETRA, you must fill the 10th variable of the first line with a string and the 1st variable of the second line also need to be filled with the same string, like +cnt1

Code: Select all

CTETRA       149       1      40      19      10      20     168     106
             196     171      66     107

For the second TETRA, the string at the 10th place, can be +cnt2
so on...

[bernd]

The file was generated with pyNastran. I used

Code: Select all

model.add_grid(1, [8000.0, 1000.0, 0.0])
...

model.add_ctetra(147, 1, [23, 12, 22, 42, 110, 122, 68, 174, 192, 184])
...

Do you know how this can be done in pyNastran?