can we use CGAP elements to represent gap between two parts(eg: 30mm) in modal and vibration analysis

NAGESWARA RAO B

Hello All,

i want to represent a gap between two parts by using spring (CGAP elements) in both modal and Vibration analysis.

I tried using CGAP elements in my assembly for modal analysis but i could not find any difference of using springs.

with and without springs modal frequencies are same. 

If you have any idea please do share your ideas/suggestions.

 

Thanks in Advance,

Nageswara Rao B

Adriano_Koga

Hi @NAGESWARA RAO B 

 

Modal and FRF are still linear analysis domain, meaning that it is not possible to consider the NL behavior of the gap elements, as you were expecting.

In modal and FRF, these gaps will act exactly as springs with same stiffness for traction and compression.

The only loadcase that would allow this as NL, would be NL TRansient analysis, but it is very computationally expensive depending on your model, and frequency of interest.

 

Can you describe better what are you trying to calculate?