NX10 Desing Simulation (Basic)

[NXerGeneration]

Hello,

Can somebody take a look at it and let me know what am I missing here? See attached.

I'm just getting into the Basic NX10 Design Simulation and I have set up a simple load case where a plunger slides into the rotating pin attached to a fixed bracket. The goal was to see what forces get transferred into the bracket but no matter what I try I get a reaction on the pin and plunger but the bracket stays cold. See attached.

 

[Toost]

these images are a little too small to see the setup.
have you created connections between the separate meshes ?
The result plot looks unexpected.


Regards,
Tomas

 

[NXerGeneration]

Hello Tomas,

Thanks for your response.

Under my initial post there is a link to the full resolution images.

I have attempted numerous mesh connections with the same result.

The link below contains all the original NX simulation files, feel free to take a look at it.

Link

Thanks
Pawel

 

[NXerGeneration]

Anybody ???

 

[FEA way]

Can you attach additional pictures: one showing the geometry/mesh alone and another with only boundary conditions and loads applied to this geometry/mesh ? Both in full resolution, like the one with results that you’ve attached to your first post. This will help us fully understand the goal of this simulation. From the deformation plot it seems that there is some error in fundamental assumptions of this analysis.

 

[NXerGeneration]

Hello,

Here is a link containing NX Simulation files >>> Link

Can you work with this?

 

[FEA way]

Currently I don't have access to NX. But I might be able to help based on the pictures that I've mentioned before since it looks like the problem is caused by wrong boundary conditions/loads or interactions.

 

[NXerGeneration]

Sounds good, three pics have been uploaded.

 

[NXerGeneration]

Two of the pics were missed in my last post, here they are agin

https://files.engineering.com/getfi...b683-5ae8ee03f518&file=boundry_conditions.JPG

https://files.engineering.com/getfi...-441d-8808-55d47bb9c94a&file=typ_3_d_mesh.JPG

https://files.engineering.com/getfi...add-b163-4a871eeef93e&file=typ_3_d_mesh_2.JPG

 

[NXerGeneration]

Here is one of the results, again I would like to know how come there is no effect on the bracket

https://files.engineering.com/getfi...4-89a9-4246-804a-60f86d1419d9&file=Strain.JPG

 

[FEA way]

It seems that your model is overconstrained. Try removing the cylindrical constraint from the pin. If you want it to rotate about the mounting holes you should define contact between these two bodies. Also remove the slider constraint from the plunger. Instead of it fix the lateral translations of the plunger’s back face (the one where force is applied).

 

[NXerGeneration]

Where do I go for "fix the lateral translations"?

 

[FEA way]

You can apply User Defined Constraint to this back face - fix X and Z translations leaving only Y translation free.

 

[NXerGeneration]

Attached image illustrates the latest setup with your suggestion, however after the solution is run for 2 minutes no results are generated.

https://files.engineering.com/getfi...2f3dde27d501&file=User_Defined_Constraint.JPG

 

[FEA way]

Are there any error messages ? It's possible that convergence difficulties occur due to initial separation of the plunger and pin. One way to solve this would be to replace the force applied to the plunger with enforced displacement. Also make sure that contact is properly defined between all parts. This includes not only plunger with pin contact pair but also pin with bracket and internal part of the pin with external part of the pin (if they are modeled as separate bodies).

 

[NXerGeneration]

Hello.

After applying a force and enforcing DOF in the direction of plunger travel and applying a pin constrain to the roller I finally got a satisfactory solution. All your suggestions indirectly help me understand how to constrain this simulation. Thank you for all your efforts.

https://files.engineering.com/getfi...9-7df7-4f84-9878-1f8dcd1d25a6&file=result.gif

https://files.engineering.com/getfi...ed-4c86-8453-3a8548be9ad9&file=Solution_2.JPG

 

[NXerGeneration]