Learning Forum

[Furqan]

I am simulating a 2D multispecies model. The domain is a rectangle with velocity inlet at bottom and pressure outlet at top. There is air in the domain and vapor enters into the domain from bottom velocity inlet. I want to apply Neumann boundary condition for vapor concentration on left and right wall. Can anyone help me how to apply Neumann Boundary Condition for vapor concentration on wall?

[Rob]

What are you trying to control?

[Furqan]

Actually I am not controlling anything. I am just capturing partial pressure of vapor at different instances. For that I have already used the (molef*total pressure), but the vapor coming from the bottom inlet is making a very sharp curved profile as I have applied adiabatic wall boundary. I have been asked to apply Neumann Boundary condition on left and right wall and check this vapor profile in that BC.

[Rob]

Which is a numerical method according to Wikipedia. What do you want to control - species, temperature, heat flux etc? 

[Furqan]

The species concentration

[Rob]

Have a look at the options in the wall boundary condition panel. What physical mechanism are you trying to replicate?

[Furqan]

Basically this is my question. Which option should I select in the wall boundary condition panel that will make the walls as "Neumann Boundary"

[Rob]

I don't know: we set the boundaries to replicate the physics/conditions we wish to model. So, fixed concentration, temperature, heat flux etc.