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Arrhenius equation for combustion - numerical stiffness issue

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Old   June 19, 2021, 01:43
Default Arrhenius equation for combustion - numerical stiffness issue
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Manu Kamin
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I am using a compressible LES solver with explicit time marching schemes to perform a combustion computation. I use 2 step reaction equation to model combustion of kerosene. Arrhenius equation is used to determine the rate of reaction.

Now the thing with Arrhenius equation is that there is a very large increase in the reaction rate at higher temperature, and therefore a very large increase in temperature within a small timeframe. While performing computations, this translates to a large source term within a time step of the code, and therefore poses numerical stiffness problem.

However I know that there have been groups that have performed such 2-step chemistry computations using explicit time marching codes before. Can anybody guide me how this stiffness issue can be overcome?
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