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Negative mass fraction problem

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Hi all,

I am trying to simulate a furnace that has combustion reaction using a stationary solver. I use eddy dissipation model. Turbulence is modeled using k-eps model. I use transport of concentrated species module from COMSOL. For the given values of velocity and mass fraction as boundary condition, I get negative mass fractions of chemical species after convergence. I read the COMSOL knowledge base about avoding negative concentrations. The mesh refining solution works when the boundary condition of velocity if lowered. However, for required boundary condition of velocity, I still have a problem. I also tried using auxilary sweeping velocity from lower to required velocity value.

Thank you in advance!

Regards, Prajakta Nakate TU Delft Netherlands


0 Replies Last Post Nov 12, 2018, 9:18 a.m. EST
COMSOL Moderator

Hello Prajakta Nakate

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