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error messege

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Hi,

I am trying to simulate temperature changes due to a serias of short electrical pulses. I created a floor function fot the pulses ((t/0.250)<((floor(t/0.250)+0.00050/0.250)- 50microsecond pulses with a 250 millisecond interval) but when I compute the simulation I get an error messege that I may have reached a point of singularity. How do I fix the problem?

Thanks
Shirley

1 Reply Last Post 22.01.2012, 17:30 GMT-5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 22.01.2012, 17:30 GMT-5
Hi

there are several threads on pulse trains, check the forum, I prefer to use the rectangle operator, and then combine with a analytical operator in repeat modus. This makes a smooth transition (à la Heaviside) so that your pulses are differentiable. Then do not forget to give a time range compatible with the time steps, and use time stepping "intermediate" and not "free"

--
Good luck
Ivar
Hi there are several threads on pulse trains, check the forum, I prefer to use the rectangle operator, and then combine with a analytical operator in repeat modus. This makes a smooth transition (à la Heaviside) so that your pulses are differentiable. Then do not forget to give a time range compatible with the time steps, and use time stepping "intermediate" and not "free" -- Good luck Ivar

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