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#1 |
Senior Member
Dongyue Li
Join Date: Jun 2012
Location: Beijing, China
Posts: 849
Rep Power: 18 ![]() |
Hello guys,
Below is the pressure equation In MPPICInterFoam: Code:
fvScalarMatrix p_rghEqn ( fvm::laplacian(Dp, p_rgh) == fvc::ddt(alphac) + fvc::div(alphacf*phiHbyA) ); //Info << fvc::ddt(alphac); Below is from Jasak: HTML Code:
Thus, if you try to evaluate the ddt the way it is written, it will recognise that the field does not have the oldTime() level stored and will use the current value to initialise it. Basically, fvc::ddt(magSqr(U)) will always give you zero, which is wrong.
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#2 |
New Member
Rahul Subburaj
Join Date: Apr 2019
Posts: 2
Rep Power: 0 ![]() |
Dear Sharonyue,
I am also trying to use the MPPICinterFoam. I have a few queries: 1. In the lines of UEqn.H, there is no alphaRhoPhic term. How did they include this term? 2. rhoPhi in alphaEqn.H seems to be similar to alphaRhoPhic. Thanks in advance. |
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#3 |
New Member
Armin Alavi
Join Date: May 2019
Location: Tehran
Posts: 22
Rep Power: 7 ![]() |
Hello Dongyue
I am facing the very same problem you had, and I wonder if you have managed to solve it. I am using OpenFoam6 by the way. I would really appreciate it if you could share your idea on this problem. |
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#4 | |
New Member
Rahul Subburaj
Join Date: Apr 2019
Posts: 2
Rep Power: 0 ![]() |
Quote:
I found a way to fix this issue. Change the nAlphaSubCycles in fvSolution to 1. Apparently having more than 1 subcycles defaults the ddtalphac to zero. Hope this helps! Best regards, Rahul Subburaj |
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