Subcases in RADIOSS Block?

Altair Forum User

Hello everybody,

I have a general question regarding radioss block.

Is there a convenient way of running subcases of one model? Like in radioss bulk or Nastran one can easily define different SPC and Loadset combination and have them solved in sequence.

It seems with radioss block this function is not directly implemented.
So the question is, how else could it be done?

Basically, I have a random prismatic strucutre, that I want to load in compression and shear.
From what I understand, I have to do two completely seprate *.rad files and run the simulations seperately. I guess I could somehow do it in batch mode as well, but is that really it?

What I eventually want to do, is running a material identifiction in HyperStudy. Therefore I would ideally have the results of both load cases (compression AND shear) in the same results file.
But I havent managed to do this.

Is there a way to achieve this?

regards

Altair Forum User

Hi Ralph,

We do not see a way currently of running simultaneous subcases as in optistruct,

However you do mention about loadcases or rather different loading conditions like compression and shear applied in sequence, this however is possible and easy,

All you need to do is change the time of application of the loads in the load curve, for eg if the imposed displacement for compression is between 0.5 and 1.0 ms followed by shear from 1.0 to 1.5 ms, you can use load curves with the x values (time) of 0.5 to 1.0 ms and 1.0 to 1.5 ms respectively.

for example the first imposed displacement can have a load curve of

x = {0, 0.5, 1.0}
y = {0, 10, 10}

and the second can have a load curve of

x = {0, 1, 1.5, 2}
y = {0, 0, 0.349, 0.349}

However it is very important to understand that this will have the combined effect of both the loadcases in the results viewed at overlapping or later times, i.e. this is not individual subcases but subcases in sequence showing combined effects.

so in the above example you will see the result for both the first and second loading conditions after time 1.0 ms

Please refer to HyperWorks Solvers > RADIOSS > Large Displacement Finite Element Analysis > Block Format > HyperMesh:
RD-3599: Gasket with HyperMesh