CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   CFX (http://www.cfd-online.com/Forums/cfx/)
-   -   Wall Condensation Model (http://www.cfd-online.com/Forums/cfx/110534-wall-condensation-model.html)

 camilo_costa December 13, 2012 11:26

Wall Condensation Model

Hi!!

I need set my inlet condition with the same mass that was condensed near the wall
How can i do this?
With this function is possible?
areaInt(H2O.Condensation Mass Flux)@COLD_WALL

Thx for all!!

 camilo_costa December 13, 2012 13:03

Monitoring the pressure in the time it was found that it always increases. This means that the mass of steam entering More than out by condensation. That is, the input term for mass is greater than the condensation in the wall. However I can not find the error in my equations that was placed in a condition of entry.

 ghorrocks December 13, 2012 17:34

This means you have a multiphase simulation, so isn't what you really want to be the mass of the water phase at the inlet equals the water condensed out?

But I do not see why you are doing it this way, it does not sound physically realistic. Why not just specify an inlet with a constant volume fraction, then the water phase will naturally move from there to the area where it is condensing due to diffusion and possibly convection. This sounds like a more realistic setup.

 camilo_costa December 17, 2012 14:21

Quote:
 Originally Posted by ghorrocks (Post 397430) This means you have a multiphase simulation, so isn't what you really want to be the mass of the water phase at the inlet equals the water condensed out? But I do not see why you are doing it this way, it does not sound physically realistic. Why not just specify an inlet with a constant volume fraction, then the water phase will naturally move from there to the area where it is condensing due to diffusion and possibly convection. This sounds like a more realistic setup.

Dear Glenn Horrocks,

You were right! Isnīt necessary set the condensation rate as the same rate of evaporation. When I set the mass flux (inlet condition) constant the pressure and the temperature increase consequently the condensation rate increase too. And the mass balance is conserved.
Thx!!!

 All times are GMT -4. The time now is 16:54.