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mef in time dependent

Hello to everyone. I have one question regarding the possibility to carry out a Time Dependent Study in mef. There is one good example of Integrated Square-Shaped Spiral Inductor (www.comsol.com/showroom/documentation/model/129/) for Stationary Study in mef. Here from one side of conductor the const value of current is injected and other side is just grounded. I added time-dependent study in the Model and injected time-dependet current with the function depending on t but the solver delivers no results (empty matrix). Where can I be wrong? The time ranges were changed properly, the unit of function has been corrected. Thank you for any help or suggestions.

1 Reply Last Post Feb 11, 2013, 6:52 AM EST
Posted: 5 years ago Feb 11, 2013, 6:52 AM EST
Hi

If you check the equations, you will notice that they do NOT adapt to the "time dependent" solver settings no d/dt nor d^2/dt^2 terms.

So MEF is not set-up for time dependent values, the fact is that ACDC is based on the hypothessis that time is "instantaneous" w.r.t. the size of the objects. But you can use frequency domain to get impedance info.

So if it's to see how the system behaves w.r.t. different DC currents you can ramp that with a parametric sweep, but you do not get the ringing of the circuit in (hence no radiation of energy).
You should consider RF probably for that

It's all explained somewhere in the doc, altough somewahat scattered around

--
Good luck
Ivar
Hi If you check the equations, you will notice that they do NOT adapt to the "time dependent" solver settings no d/dt nor d^2/dt^2 terms. So MEF is not set-up for time dependent values, the fact is that ACDC is based on the hypothessis that time is "instantaneous" w.r.t. the size of the objects. But you can use frequency domain to get impedance info. So if it's to see how the system behaves w.r.t. different DC currents you can ramp that with a parametric sweep, but you do not get the ringing of the circuit in (hence no radiation of energy). You should consider RF probably for that It's all explained somewhere in the doc, altough somewahat scattered around -- Good luck Ivar

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