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April 1, 2013, 12:23 |
openfoam 2.2 force coefficients 0
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#1 |
Senior Member
Mihai Pruna
Join Date: Apr 2010
Location: Boston
Posts: 195
Rep Power: 16 |
The same dictionary worked in previous versions.
The case solves and there should be a net force because pressure integration shows a number greater than 0. Here is the forceCoeffs dictionary: Code:
forces { type forceCoeffs; functionObjectLibs ( "libforces.so" ); outputControl timeStep; outputInterval 1; patches ( "vol1face1" "vol1face2" "vol1face3" "vol1face4" "vol1face5" "vol1face6" ); pName p; UName U; rhoName rhoInf; // Indicates incompressible log true; rhoInf 1; // Redundant for incompressible liftDir (-0.000000 1.000000 0.000000); dragDir (1.000000 0.000000 0.000000); CofR (0.72 0 0); // Axle midpoint on ground pitchAxis (0 0 1); magUInf 100.0000; lRef 1.0000; Aref 6.0000; } |
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April 1, 2013, 13:14 |
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#2 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
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Hi Mihai,
I haven't tested this, but comparing the tutorial "tutorials/incompressible/simpleFoam/motorBike" between versions:
Code:
binData { nBin 20; // output data into 20 bins direction (1 0 0); // bin direction format gnuplot; cumulative yes; } Best regards, Bruno
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April 1, 2013, 14:57 |
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#3 |
Senior Member
Mihai Pruna
Join Date: Apr 2010
Location: Boston
Posts: 195
Rep Power: 16 |
Bruno
I tried to add that part and got an error. |
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April 1, 2013, 17:45 |
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#4 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,975
Blog Entries: 45
Rep Power: 128 |
Hi Mihai,
Now I'm confused... I've ran just now the same "motorBike" case from 2.1.x, but on 2.2.0 and 2.2.x and it calculated the forces... although I haven't compared the results... But one thing I noticed in the file "log.simpleFoam" is that it made a lot of complaints about the div schemes: Code:
--> FOAM Warning : From function gaussConvectionScheme in file finiteVolume/convectionSchemes/gaussConvectionScheme/gaussConvectionScheme.H at line 123 Reading "/home/bmss/OpenFOAM/bmss-2.1.x/run/tutorials/incompressible/simpleFoam/motorBike/system/fvSchemes.divSchemes.div(phi,U)" at line 30 Unbounded 'Gauss' div scheme used in steady-state solver, use 'bounded Gauss' to ensure boundedness. To remove this warning switch off 'boundedGauss' in "/home/bmss/OpenFOAM/OpenFOAM-2.2.x/etc/controlDict" smoothSolver: Solving for Ux, Initial residual = 0.226116, Final residual = 0.0133515, No Iterations 2 smoothSolver: Solving for Uy, Initial residual = 0.275451, Final residual = 0.0161505, No Iterations 3 smoothSolver: Solving for Uz, Initial residual = 0.172255, Final residual = 0.0161645, No Iterations 2 GAMG: Solving for p, Initial residual = 0.106832, Final residual = 0.00781284, No Iterations 2 time step continuity errors : sum local = 0.0152865, global = 0.00268025, cumulative = 0.00268025 --> FOAM Warning : From function gaussConvectionScheme in file finiteVolume/convectionSchemes/gaussConvectionScheme/gaussConvectionScheme.H at line 123 Reading "/home/bmss/OpenFOAM/bmss-2.1.x/run/tutorials/incompressible/simpleFoam/motorBike/system/fvSchemes.divSchemes.div(phi,omega)" at line 32 Unbounded 'Gauss' div scheme used in steady-state solver, use 'bounded Gauss' to ensure boundedness. To remove this warning switch off 'boundedGauss' in "/home/bmss/OpenFOAM/OpenFOAM-2.2.x/etc/controlDict" smoothSolver: Solving for omega, Initial residual = 0.00480145, Final residual = 0.000399432, No Iterations 3 --> FOAM Warning : From function gaussConvectionScheme in file finiteVolume/convectionSchemes/gaussConvectionScheme/gaussConvectionScheme.H at line 123 Reading "/home/bmss/OpenFOAM/bmss-2.1.x/run/tutorials/incompressible/simpleFoam/motorBike/system/fvSchemes.divSchemes.div(phi,k)" at line 31 Unbounded 'Gauss' div scheme used in steady-state solver, use 'bounded Gauss' to ensure boundedness. To remove this warning switch off 'boundedGauss' in "/home/bmss/OpenFOAM/OpenFOAM-2.2.x/etc/controlDict" smoothSolver: Solving for k, Initial residual = 1, Final residual = 0.0477205, No Iterations 3 ExecutionTime = 12.15 s ClockTime = 12 s And what was the error you got when you used the "binData" entry? Best regards, Bruno
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April 1, 2013, 18:54 |
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#5 |
Member
Dan Kokron
Join Date: Dec 2012
Posts: 33
Rep Power: 13 |
Bruno,
I got those same warnings when I converted from 2.1.x to 2.2.x. They are just informational. The numerics didn't change when I re-ran my case with the now recommended 'bounded' schemes. See http://www.openfoam.org/version2.2.0/numerics.php for the details. Dan |
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April 2, 2013, 05:51 |
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#6 |
New Member
Håkon Bartnes Line
Join Date: Mar 2013
Posts: 27
Rep Power: 14 |
I had the same problem when I upgraded from 2.1 to 2.2. Apparently a bug was introduced in the latest update so that if you record the forces on several surfaces, only those on the last surface in your list will be written to file.
If you define the body on which you wish to measure the forces as a single surface, it'll probably work, but the bug has been fixed in the latest git release. Read this thread for more info: http://www.cfd-online.com/Forums/ope...s-airfoil.html |
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August 7, 2014, 08:22 |
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#7 |
Senior Member
harshawardhank
Join Date: Mar 2014
Posts: 209
Rep Power: 13 |
Unbounded 'Gauss' div scheme used in steady-state solver, use 'bounded Gauss' to ensure boundedness.
when I use bounded Gauss it produce following error floating point error with unbound 'Gauss' it not produce any error |
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January 19, 2017, 10:25 |
Same problem
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#8 |
Member
sibo
Join Date: Oct 2016
Location: Chicago
Posts: 55
Rep Power: 9 |
Hi guys,
how did you solve this problem? I run into the same problem here. Unbounded 'Gauss' div scheme used in steady-state solver, use 'bounded Gauss' to ensure boundedness. Although there are many warnings, there is no error. Can we ignore this warning? I am using the OpenFOAM-3.0.1 Thanks a lot! |
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February 1, 2017, 06:23 |
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#9 |
New Member
Marija Bervida
Join Date: Mar 2016
Location: Slovenia
Posts: 9
Rep Power: 10 |
Hi Sibo,
I am also using OF 3.0.1., and I got same wqarnings. After adding in fvSchemes: div(phi,T) bounded Gauss upwind; the warnings dissapeared, and the simulation runs without any errors.
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February 19, 2017, 08:32 |
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#10 |
Member
sibo
Join Date: Oct 2016
Location: Chicago
Posts: 55
Rep Power: 9 |
Thanks for your reply!!
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