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Paul October 4, 2003 16:33

Domain size change.

I am trying to model a granular flow through a clyinder. My domain is the granular bed. There is a chemical reaction in the bed involving phase change in the bed. Due to the reaction the bed shrinks in size. Is it possible in Fluent to have a adaptive top surface boundary which changes with the reduction of mass in the domain as the density and velocity remain constant?


thomas October 6, 2003 02:45

Re: Domain size change.
Hi, Apparently your problem seems pretty complex but solvable. My suggestion would be to use a Dynamic Mesh adaptation which will resize your bed height depending on the mass reduction or production. To define how your mesh has to move you will have to create a UDF describing the 'motion' profile of the boundary condition. I do not remember what parameter you have to give Fluent -> check an example of dynamics mesh but I think you have to give 2 parameters : (time, velocity). Some default parameter you can change in the dynamic mesh panel will do the rest of the work ( size of the new cell, ect ect ...).

Hope this is enought clear to give an idea of what you could do. Just know that you might get some trouble with your outlet boundary condition due to the moving mesh. Before creating your UDF just use the dynamic mesh option with a simple profile for your boundary condition like an oscilation, or just translation ....)

good luck.

Paul October 11, 2003 16:34

Re: Domain size change.
Thanks Thomas

I will look into dynamic meshing.

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