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Concentration Source Term in Wrong Units?

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Hello,

I'm trying to set up a 1d, axisymetric, reaction-diffusion problem.

I'm using 'coeffecient form' of the PDE

My dependent variable in concentration in [mol/m^3]

My source term should be a concentration addition rate in [mol/m^3-s], but I don't see it listed.

If I use the existing concentration in [mol/m^3] as my source term, my diffusion coeffecient ends up in the wrong units as [m^2]. My diffusion coeffecient is in [m^2/s].

How do I get this equation in terms of rates?


1 Reply Last Post Nov 15, 2018, 2:03 p.m. EST
Jeff Hiller COMSOL Employee

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Posted: 5 years ago Nov 15, 2018, 2:03 p.m. EST
Updated: 5 years ago Nov 15, 2018, 2:09 p.m. EST

Could the issue be that your model is stationary as opposed to time-dependent, and therefore time is not defined?

Jeff

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Jeff Hiller
Could the issue be that your model is stationary as opposed to time-dependent, and therefore time is not defined? Jeff

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