Hi there
I used to solve eigen frequency of a piezoelectric diaphragm with Comsol 3.5 and obtain real values for the eigen frequencies as real numbers. But now that I use version 4.3 for the same problem Comsol gives complex values for eigen frequencies. I am sure that I did not include any damping in the system. I can imagine the complex part of the eigen frequency is related to phase difference for higher modes when different locations on the diaphragms may have out of phase vibrations with respect to each other and that is why only for the first mode the phase is zero and the eigen frequency is real. But I am now only concern about the eigen frequency. How can I change the setting so that I see the real part of eigen frequency only?
I used to solve eigen frequency of a piezoelectric diaphragm with Comsol 3.5 and obtain real values for the eigen frequencies as real numbers. But now that I use version 4.3 for the same problem Comsol gives complex values for eigen frequencies. I am sure that I did not include any damping in the system. I can imagine the complex part of the eigen frequency is related to phase difference for higher modes when different locations on the diaphragms may have out of phase vibrations with respect to each other and that is why only for the first mode the phase is zero and the eigen frequency is real. But I am now only concern about the eigen frequency. How can I change the setting so that I see the real part of eigen frequency only?