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How to add a static current in Electromagnetic wave transient study

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Hi,

I am working on a problem using electromagnetic waves transient module. I want to study the interaction between incident EM waves and an annulus conductor in which a static current is flowing on it.

It is easy to set up the incident EM waves using scattering boundary condition. My question is how can I establish the static current in the annulus conductor?

I can establish a static current in AC/DC module, such as the MEF study by putting a voltage difference on the two ends of the conductor. But it seems in electromagnetic waves transient study I can not define a voltage on the conductor end.

Any comment would be highly appreciated.

Zhang

2 Replies Last Post 2016年4月29日 GMT-4 01:28
Robert Koslover Certified Consultant

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Posted: 9 years ago 2016年4月28日 GMT-4 22:42
You can specify a current density without a time dependence.
Bear in mind that in a true full-wave formalism, there is no unique "voltage difference" between two locations, since the path-integral of E dot dL between any two points becomes path-dependent. So, I recommend you specify something else that is less ambiguous physically, such as (as you said) a current density, or a field, or perhaps even use a lumped port.
You can specify a current density without a time dependence. Bear in mind that in a true full-wave formalism, there is no unique "voltage difference" between two locations, since the path-integral of E dot dL between any two points becomes path-dependent. So, I recommend you specify something else that is less ambiguous physically, such as (as you said) a current density, or a field, or perhaps even use a lumped port.

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Posted: 9 years ago 2016年4月29日 GMT-4 01:28
Dear Robert,

Thanks for your kind response. I understand your point that voltage is not well defined in full-wave formalism since curlE is not zero in dynamic case. Therefore voltage can not be used as the dependent variables in EM wave module. However in EC or MEF module, it can be used as the dependent variable.

So just forget the voltage. What I need in EM wave transient study is a static current propagating in the conductor and such current distribution CAN also be affected by other input such as the incident magnetic field through effects such as Hall effect. I am afraid that if I specify a current density without time dependence, this current density will be treated as a constant or external current density that will not be changed by other effects in my simulation process. Maybe lumped port is a choice?

Regards,
Zhang
Dear Robert, Thanks for your kind response. I understand your point that voltage is not well defined in full-wave formalism since curlE is not zero in dynamic case. Therefore voltage can not be used as the dependent variables in EM wave module. However in EC or MEF module, it can be used as the dependent variable. So just forget the voltage. What I need in EM wave transient study is a static current propagating in the conductor and such current distribution CAN also be affected by other input such as the incident magnetic field through effects such as Hall effect. I am afraid that if I specify a current density without time dependence, this current density will be treated as a constant or external current density that will not be changed by other effects in my simulation process. Maybe lumped port is a choice? Regards, Zhang

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