Learning Forum

[Naveed]

Hi everyone!

I have successfully simulated quarter car using Rigid Dynamics. Now I am attaching Transient Structural in project schematic to get the stresses. Problem is that I am unable to apply any force or pressure on any of the faces of my model. It is not recognizing the selection and field stays yellow as seen in picture attached. When I solve, it says "rigid bodies are invalid as a geometry selection". Scratching my head since morning, I couldn't find a solution online. Would appreciate if someone helps.

Also, mesh generation is successful, but I cannot see it. May be it is related to the problem..

Thanks in advance.

 

[peteroznewman]

Delete the links from the Rigid Dynamics system to the Transient Structural system so you can change the bodies from Rigid to Flexible.

[Naveed]

All three links? But I want to link them because geometry and model are same for transient structural..?

[peteroznewman]

Two links, Geometry and Model. The Model is not the same if you use Rigid bodies in one and Flexible bodies in the other.

You can have two models share the same geometry if you build the Project like this:

Or like this if you want to share Engineering Data too.

[pdurgaprasad2690]

Hi, peterozewman,

Need your support in Contact Analysis,

i want to simulate compound cylinders and would like to see contact pressure developed due to interference, no force applied.

will you please help me?

i have modeled 3D quarter model of compound cylinders.

i am confusing with boundary conditions where i have to give frictionless support and fixed support

and it is asking for structural load at least one.

Help me in this

any suggestion is appreciated

Thanks 

Durgaprasad 

[Naveed]

Thanks Peter for pictorial explanation. I wonder why isn't it same if I just share geometry from rigid dynamics to transient structural. Anyway, I will try your method. Thanks again..

[peteroznewman]

Hi Durgaprasad,

Please copy the contents of your post above, and paste them into a New Discussion (green button) and select the Structural Mechanics section. Once that is posted, delete the post above.

It is much better for you to "own" the discussion because you will get notified of replies. And when you feel your question is answered, you can close the discussion by marking it as Solved by clicking the Is Solution link which is only visible to the original poster.

Regards, Peter

[Bhargava Sista]

A "model" includes material model, geometry, mesh and connections. The loads and BCs fall under "Setup" level.

When you share the data at "Model" level, all the model definitions such as rigid/flexible definition, material model, connections and mesh are all transferred from the upstream (Rigid Dynamics module in your case) to the downstream system (Transient structural in your case). If you wish to change something regarding the model, then you'll need to make those changes in the upstream system.

Instead, if you share just the geometry, you have the freedom of changing all the model definitions.

[Naveed]

Thanks bsista for your response. If the loads are under "setup" and it is not shared in my case then why I am unable to apply the loads? (pressure as described above). Is it because transient structural loads cannot be applied to rigid bodies?

[Bhargava Sista]

The type of load you can apply depends on the nature of the part. If it is a rigid body, then you cannot apply pressure loads on them. The pressure loads operate through a skin of elements that are attached to the underlying solid elements. In a rigid body, there are no underlying elements to take the load so the pressure load is invalid. You can define remote force/displacement on rigid bodies as they operate directly on the remote point associated with the rigid body.

[Naveed]

Alright. Thanks a lot. I am sharing "Engineering Data" and "Geometry" and now I can apply force and pressure.