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2D Plasma Simulation with Air Cooling on Dielectric/Coil Region - Error With Nonisothermal Flow

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I have not seen any tutorials or blogs of my particular problem so I'm at a loss of what to do. Here is what I expect to simulate:

I have an ICP plasma at 20 mTorr discharging a standard plasma of ~ 10^17 m-3 ne and ~ 3 eV. After some time, the plasma will heat up the dielectric and the heat will flow to the surrounding air and components. Air will flow from an inlet (due to a fan) and will cool the region via convection. The region will reach a steady state

I have "successfully" modelled the plasma as a heat source and have also included a boundary heat source between the plasma volume and the dielectric. The temperatures I am seeing after 1 hour of operation are similar to experimental results.

The problem is when I add in a turbulent flow module and I get this error:


  • Feature: Time-Dependent Solver 1 (sol1/t1) Undefined variable.
  • Variable: comp1.nitf1.u_primez
  • Geometry: geom1
  • Domain: 4 Failed to evaluate Jacobian of expression.
  • Expression: dvol_spatial(r(pi(2(comp1.ht2.d(-(comp1.ht2.res_prime((comp1.ht2.tau_primecomp1.ht2.rho)comp1.ht2.u_primez))))))) Failed to evaluate Jacobian of expression.
  • Expression: (2comp1.ht2.streamlinepir)(dvol_spatial)


I'm not sure what "comp1.nitf1.u_primez" or what it has to do with the plasma (domain 4). I have not set any flows in Domain 4. All my flow and turbulence flow is in domain 10 (Air). The only clue to this problem that I can pick out is my Multiphysics module (Nonisothermal Flow 1) has Heat Transfer: Heat Transfer in Solids and Fluids 2(ht2) <- domain 4 (plasma) is calculated in that module for heat transfer. But the nonIsothermal Flow is trying to use it to calculate flow?

Basically I just want to simulate Air cooling to a steady state. How do I overcome this issue?

I have attached my model without solutions.

Any help is appreciated!

Kind regards,

0 Replies Last Post 16 maj 2019 12:22 GMT−4
COMSOL Moderator

Hello Adetokunbo Ayilaran

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