Hello,
When running turbFoa
Hello,
When running turbFoam, I get output from the DILUPBiCG solver: "DILUPBiCG: Solving for Ux, Initial residual = 1, Final residual = 7.53093e07, No Iterations 4". But when running interFoam, i dont get any output from the momentum equations; the code looks similar. What governs the type of output? Thanks Nico 
Hi Nico,
i suppose you are
Hi Nico,
i suppose you are running the dambreak testcase, where the momentum predictor in the fvSolution file is switched off. So only the pressure equation is solved. The correct velocity results from the pressurevelocity correction. You can change that in the PISO section: PISO { momentumPredictor yes; ... } regards Christian 
perfect, thank you very much
perfect, thank you very much

Thanks to Caw for the answer, i was about to post the same question. I have some related questions:
1. What is the purpose of the momentum predictor? 2. Where I can find some theory about it? 3. With your clue we are able to see what are the residuals for the momentum equation, but, What parameters we have to change to set up the residuals limits in order to force the solver to go with the residuals below a given value (as is usual in commercial CFD codes)? Thanks in advance. 
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If the momentum predictor is switched off, the velocity fields will be gotten explicitly from the pressure equation, I guess, it is easier to implement parallel computation because only a pressure equation is solved. However, I think, if the momentum predictor is switched on, maybe we can get more efficiently during an unparellel simulation??

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Thanks Daniel for your answers, it's a pleasure for me to interact with somebody in China (actually mi first time I guess). About answers 1 & 2 I'll read these thesis, I promise. And respect answer 3, you're right, I found the info in the pdf manuals. Regards.

Daniel, I've been reading some thesis, specially the one from Jasak, it's awesone, none more clear about FVM and errors. Now I'm dealing with the interpretation of some lines of icoFoam solver, particularly with A and H operators. If we recall the annotated version from OpenFOAM Wiki:
Code:
//set up the linear algebra for the momentum equation. The flux Code:
// solve using the last known value of p on the RHS. This gives us Code:
//  PISO loop take nCorr corrector steps Code:
// take a Jacobi pass and update U. See Hrv Jasak's thesis eqn. 3.137 and Regards. 
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