[jas123]

Hello Everyone, I am trying to solve water vapor mass fraction using non reacting species transport. I have prepared a UDF too to capture adsorption of water vapor into porous media. When I use a single domain e.g. only a rectangular fluid domain and define porous media with in it, my model works fine. It means, my UDF has no problem. But when I create two domains, one is air channel and another is porous media (as shown in Simulation_Details) and there is an interface between air and porous media which is defined as wall, my model does not work (I created mesh interface properly, and coupled those two zones, so I believe mesh interface is not a reason). I set constant mass fraction as boundary condition at the wall between air and porous media. I am not sure how to set inputs for species transport model at interface between two different zones. I have attached herewith a file describing the details of my modeling procedure and model tree. I have been stuck for a month and could not move forward. If someone knows, how to solve this issue please please help me. I am using volume weighted mixing law for Density and Mass weighted mixing law for viscosity and thermal conductivity in Species Transport Model as shown in Pic. Currently I am using 4 UDS. UDS-0 calculates Meq, UDS-1 calculates M, UDS-2 calculates dM/dt and UDS-3 calculates Energy Source term as described in the governing equations in attached PDF File. So, I am not sure how to specify BC at interface walls and Inlet for above UDS. Looks like I can specify only a constant value as shown in pic attached but I don't know how to calculate that constant value.

[Akash Siddique]

Originally Posted by jas123

Hello Everyone, I am trying to solve water vapor mass fraction using non reacting species transport. I have prepared a UDF too to capture adsorption of water vapor into porous media. When I use a single domain e.g. only a rectangular fluid domain and define porous media with in it, my model works fine. It means, my UDF has no problem. But when I create two domains, one is air channel and another is porous media (as shown in Simulation_Details) and there is an interface between air and porous media which is defined as wall, my model does not work (I created mesh interface properly, and coupled those two zones, so I believe mesh interface is not a reason). I set constant mass fraction as boundary condition at the wall between air and porous media. I am not sure how to set inputs for species transport model at interface between two different zones. I have attached herewith a file describing the details of my modeling procedure and model tree. I have been stuck for a month and could not move forward. If someone knows, how to solve this issue please please help me. I am using volume weighted mixing law for Density and Mass weighted mixing law for viscosity and thermal conductivity in Species Transport Model as shown in Pic. Currently I am using 4 UDS. UDS-0 calculates Meq, UDS-1 calculates M, UDS-2 calculates dM/dt and UDS-3 calculates Energy Source term as described in the governing equations in attached PDF File. So, I am not sure how to specify BC at interface walls and Inlet for above UDS. Looks like I can specify only a constant value as shown in pic attached but I don't know how to calculate that constant value.

Hi

I'm working on the same problem ... did you solved it.. if you have please guide me and provide udf if possible

best regards
needy