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ERROR: Complex number encountered in real expression(when calculate the DEP force)

Posted 29 ott 2014, 09:59 GMT-4 RF & Microwave Engineering, Fluid & Heat Version 4.3, Version 4.3a 2 Replies

Zerong Yuan
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Hello everyone:
I use Particle tracing module for fluid to calculate the DEP force exerted on the nano-sized particles.

When calculate the DEP I encountered a problem as follows:

Complex number encountered in real expression.
- Expression: (mod1.fpt.Ftz-d(mod1.qz,t)*d(mod1.fpt.mp,t))/mod1.fpt.mp
- Geometry: Particles

Anyone can help me ?
Thanks!
2 Replies Last Post 6 mag 2017, 17:22 GMT-4
Zerong Yuan
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Posted: 1 decade ago 30 ott 2014, 09:41 GMT-4
Anyone can help me?
Thanks!
Anyone can help me? Thanks!
Bao Ho Dang
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Posted: 8 years ago 6 mag 2017, 17:22 GMT-4
I was in similar situation.
I have 3 steps: frequency domain electric current, stationary creeping flow, and time dependent particle tracing for fluid flow.
If I solve the steps in the above order, I got the same problem like yours.
If I then solve for frequency domain the second, everything is going well.
Hope this input helps.
Yours sincerely,
Bao.
I was in similar situation. I have 3 steps: frequency domain electric current, stationary creeping flow, and time dependent particle tracing for fluid flow. If I solve the steps in the above order, I got the same problem like yours. If I then solve for frequency domain the second, everything is going well. Hope this input helps. Yours sincerely, Bao.

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