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Time dependent vs frequency domain study

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Hello, I am doing a time dependent study for piezoelectric material. At the terminal boundary condition I put : V00.sin(2.pi.frq.t) where frq is the excitation frequency and V00 is the terminal voltage amplitude. In order to check the steady state value of the previous study, I performed a frequecy domain study where I replace the above input of the terminal boundary condition by V00. In this study's settings, I put frq in the checkbox labeled Frequencies. The amplitude result is largely different between both studies (5µm at steady state for time dependent and 0,25µm for frequency domain). There must be an error somewhere but I can't find it! Any help will be appreciated. Thanks in advance, Khaled HARMOUCH


4 Replies Last Post Dec 7, 2017, 8:30 a.m. EST

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Posted: 7 years ago Dec 7, 2017, 6:27 a.m. EST

Hello Khaled,

which is the length of the pulse in time domain?

Regards,

Marco

Hello Khaled, which is the length of the pulse in time domain? Regards, Marco

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Posted: 7 years ago Dec 7, 2017, 8:04 a.m. EST

Hello Marco,

The time legth is 500/frq ( ~15ms) with a time step of 0.05/frq (1.5µs).

Sincerly,

Khaled

Hello Marco, The time legth is 500/frq ( ~15ms) with a time step of 0.05/frq (1.5µs). Sincerly, Khaled

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Posted: 7 years ago Dec 7, 2017, 8:25 a.m. EST

Have you tried to input the rms valueof the wave in the frequency study?

Have you tried to input the rms valueof the wave in the frequency study?

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Posted: 7 years ago Dec 7, 2017, 8:30 a.m. EST

Due to the large difference between time dependent and frequency studies (5µm and 0,25µm).

I dont see that putting rms value might change dramatically the result!

Plus the rms value tends to decrease the displacement, therefore increase the difference between two results

Can you develop more your idea?

Regards

Khaled

Due to the large difference between time dependent and frequency studies (5µm and 0,25µm). I dont see that putting rms value might change dramatically the result! Plus the rms value tends to decrease the displacement, therefore increase the difference between two results Can you develop more your idea? Regards Khaled

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