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-   -   rho in buoyantSimpleFoam (http://www.cfd-online.com/Forums/openfoam-solving/101919-rho-buoyantsimplefoam.html)

 Akuji May 17, 2012 04:01

rho in buoyantSimpleFoam

Hello!

I try to understand how the solver buoyantSimpleFoam works. I use hotRoom for basis. I create my own geometry with heater and use the same BC.

the 1st problem, that residualas are too much (I want to have a residuals ~e-04)

The 2nd question is about rho: while iterationg I see in terminal-window:

Code:

```DILUPBiCG:  Solving for Ux, Initial residual = 0.0141216, Final residual = 0.000127767, No Iterations 1 DILUPBiCG:  Solving for Uy, Initial residual = 0.0152304, Final residual = 0.000140921, No Iterations 1 DILUPBiCG:  Solving for Uz, Initial residual = 0.0127635, Final residual = 0.000111577, No Iterations 1 DILUPBiCG:  Solving for h, Initial residual = 0.000611936, Final residual = 6.79723e-06, No Iterations 1 DICPCG:  Solving for p_rgh, Initial residual = 0.00395034, Final residual = 3.77746e-05, No Iterations 33 time step continuity errors : sum local = 2.08489e-06, global = 1.39649e-19, cumulative = 3.59289e-18 rho max/min : 1.18706 1.0768 DILUPBiCG:  Solving for epsilon, Initial residual = 0.00028293, Final residual = 2.49851e-05, No Iterations 1 DILUPBiCG:  Solving for k, Initial residual = 0.000662009, Final residual = 5.58047e-05, No Iterations 1```
The tabulated values for my boundary conditions for air are:
min 1.093
max 1.205

Results for rho calculated by openFOAM very close to tabulated values, but not the same.

Does anybody know how OF calculates rho?

 Akuji May 21, 2012 06:51

nobody knows?

 Akuji May 22, 2012 06:08

Quote:
 Originally Posted by daffodil1003 (Post 362379) Thank you so much for the post.