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some general question about step setup

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Hi!
I try to model a process of beam vibration, where I apply the linear displacement to the end of beam and then remove this displacement, because I did not define any damp in this model, the beam should vibrate freely.
I tried the following:
I built two studies of time-dependence, one for applying the displacement, the other for vibration. Specificly, I run the study one then run the study two, in this process where I take study one's results as study two's initial condition.
Actually it does work. But it seems not very convinient, because before I run study two I have to disable the prescribed displacement which I defined for study one.
I wonder whether I can make only one study including two steps for the whole process and how I can deal with this problem.
Thank you very much!

4 Replies Last Post 2012年2月24日 GMT-5 15:21

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Posted: 1 decade ago 2012年2月24日 GMT-5 14:40
you can define step-function that goes from your load value to zero (make sure it's somewhat smooth). Then define your load as function of time using the step-function created earlier.
you can define step-function that goes from your load value to zero (make sure it's somewhat smooth). Then define your load as function of time using the step-function created earlier.

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2012年2月24日 GMT-5 15:13
Hi

or you replace the first time series study by a steady state with a boundary laod of the type F=10N*(t==0). Then do not forget to add a Parameter with t=0[s] then you can run both studies (with the time series using the ss study as initial conditions)

--
Good luck
Ivar
Hi or you replace the first time series study by a steady state with a boundary laod of the type F=10N*(t==0). Then do not forget to add a Parameter with t=0[s] then you can run both studies (with the time series using the ss study as initial conditions) -- Good luck Ivar

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Posted: 1 decade ago 2012年2月24日 GMT-5 15:18
thank you! I will try it as your suggestion
thank you! I will try it as your suggestion

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Posted: 1 decade ago 2012年2月24日 GMT-5 15:21
thank you! you mean I can define another function which is for my second part. I will try it.
thank you! you mean I can define another function which is for my second part. I will try it.

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