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negative concentrations at flux boundary results in singularity error
Posted 12.06.2020, 00:13 GMT-4 Chemical, Chemical Reaction Engineering, Electrochemistry Version 5.4 0 Replies
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greetings
I am working on a heterogenous catalysis model with fast adsorption reactions at one of the boundaries. Right near the boundary at time=0, the concentration of the species being adsorbed is very small or even negative, which causes a singularity error.
I have set my initial conditions for concentrations in transport of diluted species, so i am not sure why this is occuring at the boundary. i can avoid the singularity by setting the following initial condition in the rate expression:
( (t>0)* cCO2 + (t<=0)* 0.03 [mol/L])
(cCO2 is the concentration of the species being adsorbed, and 0.03 is the initial concentration. The rate of adsorption is modeled using Hertz-Knudsen kinetics.)
however, I was wondering if there is a better, more physically reasonable way to solve this issue?
thank you
Hello Kelsey Levine
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