contact in FRF vibration analysis if gap exist between parts

Vidyaprakash G S

Do frictional contact work in FRF vibration simulation ?

In my model part A and Part B ( both are hollow cylinders - Part A within Part B )  has a gap of 0.6 mm between them

Part A at natural frequency ,  displacement is more than 0.6 mm ( say 6 mm if no contact available between part A and part B ). Hence not able to capture the real behaviour without establishing contact between part A and Part B.

Frictional contact in my trial does not seem to work in FRF. Tied contact does not replicate the actual behaviour ( Part A and Part B should not move together. Part A should vibrate within Part B )

Kindly suggest me type of contact to be given and parameters of the contact between part A and Part B having a gap of 0.6 mm in FRF vibration analysis

 

 

Contact_question_model_picture.PNG

Adriano_Koga

FRF analysis is a linear solution, so that contact cannot be used, except freeze/tie or sliding contact.

Freeze/Tie will just bond your parts within a search tolerance.

Sliding contact, depending on your initial status, will allow only tangential movement, not normal.

NO friction is allowed.

 

For taking into account fully the contact behavior, you would need a NLTransient analysis, BUT it would be very expensive to run, depending on your model size an frequency desired.