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Define a function like Linear elastic-perfectly plastic behavior.
Posted 2013年3月3日 GMT-5 11:10 Materials Version 4.3 4 Replies
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I defined something like "F*(rm1(t<t0)+step1(t))" which step function location is time t0. the only section which I do not know if it works or not is the Ramp section. I want a ramp function which goes from 0 to 1 in time domain of 0 and t0 and after t0 ramp function become zero.
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you could combine a ramp1() with cut-off at 1 and slope 1/t0 and a step1() (from 1 to 0 at t0) and adapt the transition regions to make it nicely smooth.
Then check your time stepping to intermediate and assure enough time steps during the ramp, and at the turn down from 0 to 1 (you can combine several range(,,) 'es
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Good luck
Ivar
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Does my definition for ramp with cut of at t0 is correct? (ramp1(t<t0))
Thanks
Mahmood
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I would suggest NOT to use Booleans as these make sharp non-continuous transitions and then the solver has issues how to handle these. If you are in v4 check all the tabs and features of the Definitions Functions ramp1(...) you define the slope as 1/t0 (t0 is a Parameter you have defined ) and you limit at "1" (check on) and then you adjust the ansition times. Use the "plot" button to llok at the shape. You then call it with F0*ramp(t[1/s]) where F0 is a Parameter wit the amplitude of the ramp
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Good luck
Ivar
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