I'm having trouble with the setup on the Advection Diffusion Solver. I used mass concentrations through out. It insists that Concentration Diffusivity (CD) is missing. Is Concentration Diffusivity and Diffusion Coefficient the same thing. If not how do I find the CD value. I've had a pretty good background in theoretical Physics but the diffusion area (Ficks Law for instance ) eludes me.
Gary R
Definition of Concentration Diffusivity
Re: Definition of Concentration Diffusivity
Hello,
Take a look at the Electrokinetics tutorial, it includes the keyword Concentration Diffusivity. From looking at some literature articles, CD and DC are the same.
Rich.
Take a look at the Electrokinetics tutorial, it includes the keyword Concentration Diffusivity. From looking at some literature articles, CD and DC are the same.
Rich.
Re: Definition of Concentration Diffusivity
It seems that the advection-diffusion solver reads the diffusion coefficient from the keyword command in the form
my_solver_variable Diffusivity = Real ...
where the part "my_solver_variable" should be the string which is used as the value of the solver variable. That is, the command
Concentration Diffusivity = Real ...
works only when the solver variable is "Concentration".
-- Mika
my_solver_variable Diffusivity = Real ...
where the part "my_solver_variable" should be the string which is used as the value of the solver variable. That is, the command
Concentration Diffusivity = Real ...
works only when the solver variable is "Concentration".
-- Mika
-
- Site Admin
- Posts: 4812
- Joined: 22 Aug 2009, 11:57
- Antispam: Yes
- Location: Espoo, Finland
- Contact:
Re: Definition of Concentration Diffusivity
The reason for this is that while usually there is only one Navier-Stokes or Heat equation there can be a number of transport equation. Think of transport of different chemicals, for example. Each of them with different sources, diffusion coefficients etc. -Peter