## General Mechanical

#### concentric springs of unequal length

• laneeth
Subscriber

I want to do a static analysis of concentric spring of unequal length. I want the plate attached to the outer spring to detect the inner spring as it deflects downwards. A force of 150 KN is applied on the top plate. I have tried many methods but the plate just passes through the inner spring without detecting it. How do I solve this problem?

• jj77
Subscriber

I assume that you have defined contacts between the parts that will interact with each other.

If you have done that then I would suggest to apply a displacement on the face instead of a force, and gradually move the plate - to get the applied force just look on the reaction there.

• peteroznewman
Subscriber

• laneeth
Subscriber

Image of my model

• laneeth
Subscriber

I need to find how the system will behave when 150 KN is applied to it.

• jj77
Subscriber

Assuming this is all quasi static, then use linear static, and instead of a force (remove it) use an enforced displacement on top to press down the upper plate.

To see the force just use a force reaction probe. From there you can read of and see what kind of deformation one gets at 150 kN.

Finally increment the enforced displacement using sub-steps say (10 -1000 depending on how much disp. you apply)