COMSOL example model results do not match with Mathematical Model

AI Thread Summary
The discussion highlights a discrepancy between resonance frequencies obtained from a COMSOL example model for a cantilever beam and those calculated using Euler beam theory. The COMSOL model yields six resonance frequencies, with significant differences appearing after the second frequency compared to the theoretical values. Users are prompted to consider the boundary conditions defined in the model, as these may impact the results. The inquiry suggests a need for clarification on the model setup and its appropriateness for the intended analysis. Understanding these factors is crucial for accurate frequency response analysis in structural mechanics.
Oscar6330
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Hi! I started to look into freq response analysis of a cantilever beam using COMSOL. Luckily COMSOL already has an example model "Model Library>> Structural mechanics module>>Dynamics and Vibrations>>rotating blade". While not changing anything in the model and with Omega=0 and Cloris =0, I get the following results

Resonance Freq1 = 84.36
Resonance Freq2 =528.84
Resonance Freq3 =949.31

Resonance Freq4 =1316.00
Resonance Freq5 =1481.41
Resonance Freq6 =2882.00

But Euler beam theory (options>>constants) gives me the following

Resonance Freq1 = 84.36
Resonance Freq2 =528.66
Resonance Freq3 =1862.89

Resonance Freq4 =3650.55
Resonance Freq5 =6034.61
Resonance Freq6 =9064.89

Clearly the results do not match after 2nd natural/ resonance freq. I am quite sure that COMSOL example model cannot be wrong but there is something odd. Some elaboration would be appreciated
 
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You're wanting to solve a cantilever beam modal analysis, but used a rotating blade vibration analysis. How are the boundary conditions defined?
 
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