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Error in temperature calculation in a laminar reacting flow

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I am simulating a simple one-step reacting flow in a 2D domain. I started with a 0D Reacting Engineering physics, and led it to a 2D problem by the function "Generate Space-Dependent Model".

The simulation ran well when I only added "Transport of Concentrated Species" model and "Laminar Flow" model. However, when I added "Heat Transfer in Fluids" model (still via "Generate Space-Dependent Model" function), set the parameters and ran it again, the error message appreared as below:

Error evaluating thermodynamics function.
  - Error message: Temperature must be positive real value
  - Function: chem1pp1rho_mixture

After this one are a list of "Failed to evaluate variable" errors, which I think are because of the above-mentioned error.

The domain is simply rectangular with a small inlet, an outlet, a symmetric boundary and walls. The reference temperature is kept unchanged as 293.15K. I tested the upstream and initial temperature values from 300K to 1400K while there were always errors. I also tested the case with no heat source (by setting heat source with a zero heat rate instead of "Heat source of reaction"), but the errors still existed.

I am grateful for any idea or discussion to help locate the problem. Hope to hear from you.


0 Replies Last Post 18.05.2021, 20:53 GMT-4
COMSOL Moderator

Hello Shiyao Ni

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