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No change in phase change using interPhaseChangeFoam |
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August 22, 2014, 09:57 |
No change in phase change using interPhaseChangeFoam
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#1 |
New Member
Reza
Join Date: Feb 2013
Posts: 8
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Hello friends,
I would like to simulate pool boiling in a box, using interPhaseChangeFoam. I am using OpenFOAM 2.3. However, I cannot see any change in alpha.water, although the temperature of the walls are higher than saturated temperature. Is anybody here to help me? Thanks, Reza |
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August 22, 2014, 12:08 |
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#2 |
New Member
Reza
Join Date: Feb 2013
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That's very weird since the temperature field covers a broad range of temperature, including below and above the saturation temperature. However, I don't see any change in alpha.water as such it remains one.
Have you ever encountered this issue? Thanks |
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August 22, 2014, 15:14 |
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#3 |
New Member
Reza
Join Date: Feb 2013
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I think I got the reason, however I cannot solve the issue.
In fact, I am modifying the interPhaseChangeFoam based on the work by Andersen at http://www.tfd.chalmers.se/~hani/kur...ChangeFoam.pdf When I add the temperature equation, I cannot see change in volume fractions of water. Is there any comment, help? Thanks |
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August 24, 2014, 10:41 |
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#4 |
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Reza
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Seems nobody is interested.
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August 24, 2014, 10:44 |
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#5 |
New Member
Reza
Join Date: Feb 2013
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The problem in this work is that I get negative temperature.
Do you have any clue to resolve this problem? Thanks |
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August 26, 2014, 15:36 |
Bug in interPhaseChangeFoam 2.1.x
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#6 |
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Parisa
Join Date: Feb 2013
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Hey Reza,
Did you solve your problem? Please let me know since I think my case is very similar to yours. Thanks, Parisa ----- I am aware that there have been lots of discussions about bugs in interPhaseChangeFoam in 2.1.0 and then the bug was resolved in 2.1.x. However, I am following the tutorial by Martin Andersen and I added the energy equation as well as temperature dependent PSat. But, I got completely unrealistic results. PSat become zero in many places in the domain since the temperature dropped much below zero. Is there any solution for that? Thanks, Parisa Last edited by wyldckat; August 30, 2014 at 09:36. Reason: merged 2 threads on the same topic, and merged two posts to make it a bit more consistent |
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August 26, 2014, 15:42 |
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#7 |
Member
Parisa
Join Date: Feb 2013
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Please let me clarify myself.
The energy equation is solved without any problem, and actually I obtained reasonable temperature distribution. However, as soon as the temperature dependent PSat is inserted, the solver becomes confused and generate some unrealistic results. So, I think the problem is coupling between PSat and temperature distribution. I appreciate if you help me at this. Thanks, Parisa |
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August 26, 2014, 18:18 |
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#8 |
Member
Parisa
Join Date: Feb 2013
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I also have the same problem with OpenFOAM 2.2.x.
Any help? |
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August 27, 2014, 13:40 |
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#9 |
Member
Parisa
Join Date: Feb 2013
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Just more updates on my problem.
I am solving the same case in OpenFOAM 2.3. In fact there is no phase change inside the domain. I am looking forward to hearing from you guys, Thanks, Parisa |
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August 27, 2014, 19:14 |
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#10 |
Member
Parisa
Join Date: Feb 2013
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Please, I am really anticipating any kind of help.
Parisa |
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August 30, 2014, 09:44 |
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#11 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
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Greetings to all!
I've merged your two threads into a single one, since almost the exact same problem. This way it makes it easier for other people to find this thread to help or to find help in any answers that can arise. Regarding your questions, I've taken a quick look at the PDF by Andersen, that Reza pointed out, and the first detail that popped up to me was: the original author used OpenFOAM 2.0.x. Now, you might not be familiar with how OpenFOAM evolves over time, but from personal experience I can tell you that solvers can change considerably between versions of OpenFOAM, therefore the probabilities of making an example that works on 2.0.x, work on 2.1.x or 2.3.x, requires some considerable time and experience. Therefore, the first step you should take is to install OpenFOAM 2.0.x and then test the case with that version. Secondly, it takes quite some time to set-up an example case that you're working on, therefore it makes it a lot harder for someone with more experience to step in and spend 2-5h trying to reproduce the same steps. Therefore, please read, study and follow these instructions: http://www.cfd-online.com/Forums/ope...-get-help.html Best regards, Bruno
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September 4, 2014, 17:18 |
Follow up
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#12 | |
New Member
Reza
Join Date: Feb 2013
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First of all thanks from wyldckat for the nice and professional explanation.
Parisa: I am sorry for delay in response. I solved that issue. However, I am changing the solver and I am using interFoam. I updated the solver with mass transfer and temperature distribution. I hesitate sending the code to you since it's not complete yet. Maybe the experts can help me, then I will resolve the problem and make the code ready for you. The problem is that the code is running for some time steps, I get boiling, and/or condensation. The results are convincing and somehow I validated with some solid results. However, after a while, the courant number increases rapidly and the rsults are ruined such that the volume fractions reach to -50 and +600. I use very low deltaT, and also adjustdeltaT is on. Any help, comment. suggestion from experts? Thanks everybody for the nice cooperation. Reza Quote:
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September 6, 2014, 14:38 |
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#13 | |
Retired Super Moderator
Bruno Santos
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Hi Reza,
Quote:
Bruno
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March 29, 2015, 06:07 |
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#14 | |
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Hi Reza,
I am interested in condensation and do you think interFoam is more suitable to solve the problem in comparison to interPhaseChangeFoam? Did you managed to solve the problem? Thanks in advance! best regards, Quote:
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April 17, 2015, 23:16 |
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#15 |
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Mihai Pruna
Join Date: Apr 2010
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there is one extra step for Martin Andersen's tutorial that is not specified I believe:
you have to recompile the phaseChangeTwoPhaseMixture, by going in that folder and typing wclean and then wmake. Make sure you first go in the file called files in the make folder in phaseChangeTwoPhaseMixture and change to LIB= $(FOAM_USER_LIBBIN) etc instead of $(FOAM_LIBBIN) then (dunno if you need to do that) do wmake from the myInterPhaseChangeFoam folder This at least makes the alpha change, not sure about the results
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April 21, 2015, 06:39 |
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#16 | |
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thanks for the answer!
did you implement is to latest version of OF or 210? Quote:
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April 21, 2015, 08:59 |
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#17 |
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Mihai Pruna
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Version 2.3.1
The tutorial should be applied pretty much the same way except for the extra compilation for the libraries i mentioned Also there is a Tfinal field in fvSolution which I made the same as T, not sure what it does yet You don't have to do this part: #include "../interFoam/correctPhi.H" I am still having issues with Courant number blowing up
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April 24, 2015, 09:17 |
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#18 |
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Mihai Pruna
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I think I have figure out how to get decent behavior, with decent time step size that allows you to simulate over longer periods of time.
I believe the evaporation rate was unphysical. I used the Kunz model into the transport properties and looked deeper into how the coefficients are determined: dimensionedScalar UInf_; dimensionedScalar tInf_; dimensionedScalar Cc_; dimensionedScalar Cv_; Uinf is the reference velocity, I set it to something like 1m/s. tinf I set dividing the diameter of the vessel by Uinf. Cc_ and Cv_ are proportional to the phase change rate.In a nutshell, the smaller they are, the smaller the evaporation rate, which would in turn lowers the maximum Courant number it gets to. In this paper: http://www.personal.psu.edu/faculty/...MEsummer99.pdf they were set to 0.2, which are values determined experimentally. Of course, you might have to set different numbers, especially since you are not doing cavitation, but rather, boiling. What I plan to do next is correlate the volume fraction/time obtained from CFD with a simple system analysis spreadsheet I did for my vessel, where I can vary some parameters and observe the boiling through basic formulas independent of geometry save for general sizing. Then I will change the Cc_ and Cv_ values accordingly to match the same evaporation rate on gross terms.
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May 27, 2015, 04:14 |
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#19 | |
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Hi,
I am not getting the correct results from when I set the inlet BC for alpha =0 which is vapur...I do not see any condensation in side the tube..what kind of geometry are you using? I am trying t simulate pipe flw but I am not sure about alpha and p_rgh BC? do you have any idea? Thanks in advance! Quote:
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May 27, 2015, 07:45 |
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#20 |
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Mihai Pruna
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As I posted earlier in the thread, to get it to work for me, I had to recompile
phaseChangeTwoPhaseMixture
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