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Exotherm reaction in PFR

Jose Juan Bolivar Caballero

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Hi everyone,

I am really new to Comsol and I am trying to model an exotherm reaction in a plug flow reactor: Species A reacts irreversible (first reaction order), the rate reaction is defined as rA=-krcA* where kr=Aexp(-E/(RT)) Since it is a exotherm reaction, the temperature is going to increase as species A reacts, which changes the value of kr. T is described as a differential function vCpdT/dz=(-HkrcA) - ah(T-Tw) So, these two are coupled since cA depends on kr that depends on T and T depends on cA. The wall of the reactor is held constant (adiabatic).

I assume steady state (time independent), cA & T depend just on Z-axis (along the reactor).

I have used "Transport of Diluted Species" to model the change in concentration since I have diffusivity. I have tried to use Global ODEs & DAEs to solve the differential form of the temperature without success.

Does anybody know how to proceed in order to get concentration and temperature profile along the reactor?

Thank you!


1 Reply Last Post 24.09.2019, 08:33 GMT-4

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Posted: 5 years ago 24.09.2019, 08:33 GMT-4

Why don't you use ready made physics? Combine your reaction with heat transfer in fluids.

Lasse

Why don't you use ready made physics? Combine your reaction with heat transfer in fluids. Lasse

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