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July 8, 2009, 03:35 

#21 
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isabel
Join Date: Apr 2009
Location: Spain
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I only have advisors this week. I am at a OpenFOAM course, which finishes on Friday.
fv::gaussConvectionScheme<scalar>(mesh, phi, UDs).fvmDiv(phi, psi), This line is to calculate div(phi, psi). The begining is only to specify to the program how to calculate it. And the div(U) is repeated. 

July 8, 2009, 04:36 

#22 
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Sandy Lee
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Wow, it is great. Thank you very much.
By the way, what a OF course are you studying? Do you have some documents or websites to share? Sandy sandy.lee37@gmail.com 

November 5, 2009, 04:31 

#23 
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J. Cai
Join Date: Apr 2009
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Hi, everybody, I am trying to use the interPhaseChangeFoam in OpenFOAM1.6, and just meet the same problem how to set MULES::implicit in the fvSolution file. Any suggestions are appreciated.
Best regards, Chiven 

November 5, 2009, 19:48 

#24 
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Sandy Lee
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Hi Chiven, is there the tutorial about InterPhaseChangeFoam in OF1.6? I use the OF1.5.
 gamma MULESImplicit { maxIter 1000; nLimiterIter 10; maxUnboundedness 1; CoCoeff 0.2; solver PBiCG { preconditioner DILU; tolerance 1e10; relTol 0; }; }; 

November 5, 2009, 20:23 

#25  
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J. Cai
Join Date: Apr 2009
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Hi, Sandy, thanks for your reply.
I have justed used the similar setting like yours, but failed. At this time, I have NOT run the interPhaseChangeFoam successfully in OpenFOAM1.6. Code:
alpha1 { MULESImplicit { maxIter 1000; nLimiterIter 10; maxUnboundedness 1; CoCoeff 0.2; solver PBiCG { preconditioner DILU; tolerance 1e10; relTol 0; } } } Chiven Quote:


March 29, 2010, 13:20 

#26 
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Suresh kumar Kannan
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Location: Luxembourg, Luxembourg, Luxembourg
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Hello
I am planning to modify the interfoam solver of OF1.6.x with the implcitMULES and use an LES simulation. I am studying the breakup of 2D liquid sheets. I have already run some simulations in which i see that the solution is very much dependent in the CFL number I want to know th experience of other interFOAM users who have used an implicitMULES. Do you really find a difference in the solution of two explicitMULES and implicitMULES. And if yes what was the improvement. Is it advicable to give the implicitMULES a try. Will it allow me to use higher CFL numbers. bye with regards K.Suresh kumar 

April 8, 2010, 05:08 

#27 
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Suresh kumar Kannan
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Hello interFoam and interphasechange users,
I implemented the implicit::MULES in interFoam in OF1.6.x . Thanks to Niels and pbohorquez.and ran it with the LES model on some preliminary test cases. I can already see that the results are much better than the explicit::MULES case. So i have decided to further look into the implicit::MULES solver. I already read the posts in this discussion. That gave me a good idea about the form of the equation that is being solved in the two cases. But I would like to know more about the discretization of the transport equation when i am using an implicit::MULES, because i really dont get anything about the parameters that i specify in the fvSolution gamma PBiCG { MULESImplicit { maxIter 1000; nLimiterIter 10; maxUnboundedness 1; CoCoeff 0.2; } preconditioner DILU; tolerance 1e06; relTol 0; }; so it would be very useful to me if anybody gives some explanation about the discretization in the case of MULES implicit. with regards K.Suresh kumar 

July 14, 2010, 12:25 

#28 
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Nima Samkhaniani
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hi friend
the correct form of alpha fvSolution is like below : alpha1 MULESImplicit { maxIter 1000; nLimiterIter 10; maxUnboundedness 1; CoCoeff 0.2; solver PBiCG; preconditioner DILU; tolerance 1e06; relTol 0; }; 

June 17, 2011, 16:18 

#29  
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Kai
Join Date: May 2010
Location: Stockholm
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Quote:
In order to strictly restrict alpha in [0,0.52], I am now considering to use MULES in case of bubbly flow. I have a question here since in Weller's scheme, there is a compression term (eqn 4.13, Rusche). And it is said "The artificial term is only active in the thin interface region because of the multiplication term gamma(1gamma)". It is true in case of liquidvapor with clear interface which only exists somewhere. However in bubbly flow, the interface could be everywhere. I dont know if it is appropriate to use this scheme in my case. Thanks. // Kai 

June 27, 2011, 20:11 

#30 
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Sandy Lee
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You can try them, respectively. I guess, there are not differences in results but in the performance of convergence ...


July 14, 2011, 04:08 

#31 
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Pablo
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Hello Suresh,
What are the steps to update interfoam from mules::explicit to mules::implicit?? Advanced thanks, Pablo 

July 14, 2011, 05:01 

#32 
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Anton Kidess
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Pablo, simply replace the call to MULES::explicitSolve in alphaEqn.H to MULES::implicitSolve and recompile. You will need some extra entries in the fvSolution file as shown in a post earlier in this thread, and that's it.


July 14, 2011, 12:47 

#33 
Senior Member
Pablo
Join Date: Mar 2009
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Thanks Anton,
It is working, i copied from interphase tutorial; alpha1 { maxUnboundedness 1e5; CoCoeff 2; maxIter 5; nLimiterIter 2; solver PBiCG; preconditioner DILU; tolerance 1e12; relTol 0.1; }; but what mean cocoeff,maxiter and nlimiter?? 

March 27, 2012, 22:11 
report

#34 
Member
ehsan
Join Date: Mar 2009
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Hello all
Could any one share this file with me: OpenCFD, OpenCFD Technical report no. TR/HGW/02 (unpublished); 2005 Regards 

June 25, 2012, 21:41 

#35  
New Member
NieYongguang
Join Date: Sep 2010
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Quote:
So, can you give me some suggestion? 

June 25, 2012, 22:16 

#36 
Senior Member
Sandy Lee
Join Date: Mar 2009
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Hi, why you not read some papers by Dr. Lu Naixian and deduce those equations?


March 27, 2014, 13:02 

#37 
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Emeline Noel
Join Date: Dec 2013
Location: Paris
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Hi,
I think, it is not as trivial as you suggest in a not very friendly way. In addition, it is link to a query often ask in this forum and As far as I have searched I did not find an answer. If someone have any interrest on this, in can give some suggestion. Bye 

November 7, 2014, 18:20 

#38  
New Member
Cong Gu
Join Date: Jun 2013
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Quote:
I'm also confused. Have you been successful in finding why the volumetric source is formulated with this coefficient? It is the same as rho_mixture / (rho_1 * rho_2). 

July 11, 2015, 04:59 

#39  
Member
Przemek
Join Date: Jun 2011
Posts: 87
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Quote:
You can find an answer in Jibran Heider master thesis in chapter 2.1 http://www.cimne.com/cvdata/cntr2/sp...branHaider.pdf
__________________
best regards pblasiak 

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