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How can i give complex function as load?

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I am doing a plate vibration problem there the boundary phase load is f=F0e^(iwt). I tried to create this wv1 of sine function and wv2 of cosine function. In the boundary phase i just gave the load as *wv1 + iwv2 *. Then i triend to solve my problem with time dependent study type, Then it is showing error, that complex number not accepting?? Please help me?


2 Replies Last Post Sep 21, 2017, 12:34 p.m. EDT
Dave Greve Certified Consultant

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Posted: 7 years ago Sep 20, 2017, 6:35 p.m. EDT
  1. I don't understand what a "boundary phase load" is.

  2. You seem to be mixing up phasors and time-dependent quantities. Using a complex number as a load in a structural mechanics problem makes no sense. If you have only sinusoidally dependent loads at the same frequency (and you have no interest in the initial transient response) you should be using frequency dependent analysis.

D.W. Greve DWGreve Consulting

1. I don't understand what a "boundary phase load" is. 2. You seem to be mixing up phasors and time-dependent quantities. Using a complex number as a load in a structural mechanics problem makes no sense. If you have only sinusoidally dependent loads at the same frequency (and you have no interest in the initial transient response) you should be using frequency dependent analysis. D.W. Greve DWGreve Consulting

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Posted: 7 years ago Sep 21, 2017, 12:34 p.m. EDT

Thank you for your reply Mr. D Greve , I am doing a transverse vibration of plate ..I corrected my load and now i am using cosine function of the load. The frequency i applied is 95% reasonance frequency. Still i am not getting plot correctly .... Geometry: circular plate all end are clamped Load : F=Fo coswt(In z direction load distributed in centre small area of radius less than plate radius) a/h=radius of plate to thickness of plate<80 I am using general solid mechanics interface for this study.

Thank you for your reply Mr. D Greve , I am doing a transverse vibration of plate ..I corrected my load and now i am using cosine function of the load. The frequency i applied is 95% reasonance frequency. Still i am not getting plot correctly .... Geometry: circular plate all end are clamped Load : F=Fo coswt(In z direction load distributed in centre small area of radius less than plate radius) a/h=radius of plate to thickness of plate

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