Patran Results

[beginner2]

Hello all,

I am starting to learn Nastran / Patran and I have som doubts.

1. If I have one quad next to another one, a one of them have the coord.system parallel to the global, the other quad is reverse. There is impact inn my results??

2. Which is the difference between check ths stress plot with Coodinate Transformation: AS IS / CID / Projected CID / Global / Default / Material / Element IJK?

Someboy have any document which talk about axis system in nastran/patran and which is it's influence?

Thanks on advance

 

[JakeLiv]

reversing the element will mostly influence in cases of material offsets, and wrong thickness calculations.
It's a very bad way of modeling - get your normals in sync to minimize problems.

COORD systems are relevant when dealing with the following:

1. non isotropic materials.
2. checking results in different coord systems.

 

[beginner2]

Thank you!

I see...but according to this, Which Axis are used for NASTRAN solution? Global Axis, Element Axis...

 

[JakeLiv]

then you are refering to nastran translation..

if you define loads/constraints and so forth in a certain coord system, then that coord system is created in the BF file.

there is a difference between the result processing coord systems, and the solution coord systems.

 

[beginner2]

Then, Nastran output (F06) is calculate with Global Axis and then in Patran I can change the coord system?

 

[JakeLiv]

yep


as far as I know

 

[beginner2]

And there is a way to obtained F06 results according to a Axis created by me instead of Global Axis?