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April 6, 2011, 13:48 |
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#81 |
Member
Join Date: Oct 2010
Location: Stuttgart
Posts: 35
Rep Power: 16 |
hello francois,
thanks a lot for you support, i will try what you've suggested! may i ask you for another favour? could you please take a look into my post "Adding a new member function in src/../turbulenceModel" ? you could help me there big time..... best regards grandgo |
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April 7, 2011, 13:42 |
About mean value calculation for LES solverrs
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#82 |
Member
N. A.
Join Date: May 2010
Posts: 64
Rep Power: 16 |
Hey Folks,
I am wondering if in OF1.7, the way we extact mean values is by specifying following in controlDict file: U { mean on; prime2Mean on; base time; } I want to confirm if this is: Umean = time average of U at each cell ....(1) or Umean = time average of (U+ Uprime); ....(2) where Uprime is the sub-grid scale part. I want to get a average value using 2nd option to compare with time-averaged experimental data. Can comeone confirm what is OF1.7 doing with this mean function in controldict? If it is not doing 2nd option, how can I extract the mean using the second equation. Thank you, Nir |
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May 16, 2011, 05:55 |
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#83 |
Senior Member
Eugene de Villiers
Join Date: Mar 2009
Posts: 725
Rep Power: 21 |
Usgs or Uprime as you call it is an isotropic vector, so averaging it would result in a mean field of zero.
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September 23, 2011, 03:41 |
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#84 | |
Senior Member
Sandy Lee
Join Date: Mar 2009
Posts: 213
Rep Power: 18 |
Quote:
Could you explain detailed, what else are the differences between directMappedVelocityFlux and directMapped, nearestCell and nearestFace, setAverage=true and setAverage=false ? In addition, offset is just a distance but not a coordinate value from the inlet plane, right? |
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October 1, 2011, 23:49 |
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#85 |
Senior Member
Sandy Lee
Join Date: Mar 2009
Posts: 213
Rep Power: 18 |
Hi Tabor,
In your paper(Inlet conditions for LES using mapping and feedback control), you did not refer to "directMapped" method. Could you explain what are differences between directMapped with directMappedVelocityFlux ? |
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October 4, 2011, 15:38 |
Fluctuation with Profile
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#86 |
Senior Member
Seyyed Ali H.M.
Join Date: Nov 2009
Location: Utah
Posts: 107
Rep Power: 17 |
Hi Everyone,
I was reading about LES turbulentInlet boundary condition. It looks like this boundary condition does not have ability to read profile for U_mean and also U_rms, which can be used as a fluctuation scales. But it uses flat profile for both. Besides, I know there's a timeVaryingMappedFixedValue field that reads profiles for boundary conditions. My question is is there any boundary condition that reads profiles for mean velocity and their fluctuation scale (U_rms) and uses them to make a turbulent inlet for U? and If there's none, how can I make one? I know some C++ and some basics of openfoam, but it gets hard when it comes to openFOAM source code, as it has complicated structure.
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SAHM |
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December 29, 2011, 11:41 |
LES swirl inlet conditions
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#87 |
New Member
Vitaly
Join Date: Sep 2010
Posts: 6
Rep Power: 16 |
Hello,
I want to run a combustion simulation with swirling inlet conditions. How do I define the initial pertubations? As I understand it,directMapped is not suited for this purpose. I know that Dr.Tabor worked on this subject with his Phd student (now Doctor). Did someone implemented this method? What should I do? Did someone used Synthesised turbulence methods in swirl flows? (I'd rather to use the Mapped method, but beggars can't be choosers...) Thank You! |
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December 29, 2011, 15:38 |
dual fuel combustion
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#88 |
New Member
saeed divrakhsh
Join Date: Jul 2010
Posts: 8
Rep Power: 16 |
I want to simulate dual fuel diesel engine with OpenFOAM. can I simulate this with dieselEngineFoam? If not, which solver I must use?
If I can use dieselEngineFoam, can I use (CH4) mass fraction in initial condition such as O2 and N2? Thanks. Best Regards, |
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January 12, 2012, 07:24 |
Under resolved LES
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#89 |
Senior Member
Ehsan
Join Date: Mar 2009
Posts: 112
Rep Power: 17 |
Hello
I had the problem of under resolved solution of my LES simulation of cavitating hydrofoil flow. Is there any remedy for overcoming under resolved solutions? Is it filtering? Thanks |
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April 23, 2012, 16:29 |
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#90 |
Member
Santiago
Join Date: Dec 2009
Posts: 85
Rep Power: 16 |
Hi everyone. I am really desperate trying to find a way out of this problem using directmappedpatch. Please take a look. Any suggestion will be appreciated. Thanks
I'm trying to model a fluid structure interaction using LES. I generate the turbulence at the inlet implementing a recycling technique (similar to that of Lund et all) using directMapped BC. Now, my mesh has to be able to deform, however when I run my case I get: Create time Create dynamic mesh for time = 0 Selecting dynamicFvMesh dynamicMotionSolverFvMesh Selecting motion solver: laplaceFaceDecomposition --> FOAM FATAL ERROR: Unknown faceTetPolyPatchFaceDecomp type directMappedPatch. Valid faceTetPolyPatchFaceDecomp types are : 7 ( wall processor wedge patch empty ggi symmetryPlane ) From function faceTetPolyPatchFaceDecomp::New(const polyPatch&, const tetPolyBoundaryMeshFaceDecomp&) in file tetPolyMeshFaceDecomp/tetPolyPatches/faceTetPolyPatch/newFaceTetPolyPatchFaceDecomp.C at line 59. FOAM exiting Does this mean that deformable meshes cannot be used with DirectMapped Bc's? Do I have to set three different domains and link them together? (one recycling domain, one fluid domain with deformable mesh and one solid domain). Is there a way to use directmappedpatch with deformable meshes??? I will appreciate any help or suggestions. Thanks |
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May 8, 2012, 13:02 |
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#91 |
Senior Member
Hrvoje Jasak
Join Date: Mar 2009
Location: London, England
Posts: 1,907
Rep Power: 33 |
There is no reason why a direct mapped condition would be a problem: this is to do with the way constrained patches are created on fields. Some minor coding required, ie. you need a simple tet-fem wrapper for the direct mapped patch and fields.
Hrv
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Hrvoje Jasak Providing commercial FOAM/OpenFOAM and CFD Consulting: http://wikki.co.uk |
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May 8, 2012, 14:04 |
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#92 | |
Member
Santiago
Join Date: Dec 2009
Posts: 85
Rep Power: 16 |
I really, really appreciate you reply.
I'm glad to hear that directMappedPatch should not be a problem, however, would you be kind enough to be a little more specify about Quote:
Again I will be very grateful if you can give me any other hint. Thanks again |
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May 14, 2012, 17:04 |
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#93 |
Member
Santiago
Join Date: Dec 2009
Posts: 85
Rep Power: 16 |
@ Bruno,
Here I uploaded my solver and my case. The meshes are greatly simplified in order to make the folder small enough to be uploadable. The case as it is generates the error mentioned above. Please let me know if are able to run it. Thanks a lot The file my_PisoFSI is the solver and the other one is the case. |
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May 15, 2012, 17:57 |
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#94 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,982
Blog Entries: 45
Rep Power: 128 |
Greetings to all!
@Santiago: I'm not able to run you case because I get the following error when running changeDictionary in the "fluid" folder: Code:
Create mesh for time = 0 --> FOAM FATAL ERROR: Did not find sample (0.5 0.075 0.095) on any processor of region region0 From function directMappedPatchBase::findSamples(const pointField&, labelList&, labelList&, pointField&) in file directMapped/directMappedPolyPatch/directMappedPatchBase.C at line 373. FOAM aborting Best regards, Bruno
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May 15, 2012, 21:48 |
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#95 | |
Member
Santiago
Join Date: Dec 2009
Posts: 85
Rep Power: 16 |
Hi Bruno.
Thats strange. I run it here and i get Quote:
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May 17, 2012, 19:24 |
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#96 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,982
Blog Entries: 45
Rep Power: 128 |
Hi Santiago,
OK, I've made some progress. Using the old 1.6-ext deb package from the CAE-Team on Ubuntu 10.04, along with the swak4Foam also available with it, I've managed to reproduce your error. I've also started working on an independent add-on library(ies) (one for faces and another for cells, wrapped into a single source code folder), which I've attached the code for it. Nonetheless, it's not building yet. It did build with the sample folder for the "timeVarying*" BC, but I picked a bad example, since this one uses a type of data structure different from the "directMapped*" one. I'm attaching it already just in case someone else wants to step in and help! The idea is that after the libraries are built and possibly working, they are added to the libs list at the case's "controlDict". Best regards, Bruno
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June 17, 2012, 18:11 |
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#97 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,982
Blog Entries: 45
Rep Power: 128 |
Hi Santiago,
OK, I've made some advances in the research on how to wrap up "directMappedPatch" for tet, but don't have it working yet. It basically boils down to this:
edit: for using the latest 1.6-ext version, I had to change the "changeDictionaryDict" file on the fluid side from "(0.5 0.0 0.0)" to "(0.699 0.0 0.0)". Best regards, Bruno
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Last edited by wyldckat; June 17, 2012 at 18:12. Reason: see "edit:" |
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June 24, 2012, 15:20 |
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#98 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,982
Blog Entries: 45
Rep Power: 128 |
Hi Santiago,
Sadly, I'm at the limit of my experience with OpenFOAM source code Attached is what I've got now. I had to modify the case file "system/controlDict" by adding "libfaceDecompTetDirectMapped.so" to the libs list. The error I get when running the solver is this: Code:
--> FOAM FATAL ERROR: Attempt to cast type wall to type lduInterface From function refCast<To>(From&) in file /home/username/OpenFOAM/OpenFOAM-1.6-ext/src/OpenFOAM/lnInclude/typeInfo.H at line 115. FOAM aborting The other issue was that I couldn't create a proper "directMappedElementPatchFields.C", but I don't know if this is what is missing and/or wrong... Good luck! Best regards, Bruno
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March 19, 2013, 11:51 |
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#99 |
New Member
Kanuk
Join Date: Oct 2010
Posts: 28
Rep Power: 16 |
Hi Bruno,
Have you had any luck in implementing your direct mapped BC? I am really trying to implement a cyclic BC with the laplaceFaceDecomposition solver in 1.6-ext. It appears you are on the right track - though I too have limited c++ experience. Regardless, any insight you or anyone else out there has about writing the wrapper, I'd appreciate. I'll post back if I have any luck... Cheers, Dave |
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March 24, 2013, 13:08 |
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#100 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,982
Blog Entries: 45
Rep Power: 128 |
Hi David,
Unfortunately I was not able to figure out how it works and how it can be done I don't know if Santiago managed to figure out some other solution in the mean time. Best regards, Bruno
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