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March 31, 2010, 06:10 |
help: results depend on writeInterval
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#1 |
New Member
Christian Koch
Join Date: Mar 2010
Posts: 1
Rep Power: 0 |
Hi everyone !
I am using OpenFOAM for simulating solidification of a two immiscible fluids. For that, I augmented the interFoam solver with a few things such as heat-treatment, thermophysical properties and a solidification model. As you can imagine, the solver-code now looks pretty different to the original one. So far, my first runs gave me promising results. BUT yesterday when I did a long-time simulation, the results differed heavily from former ones. My first runs, which gave me physically feasible results, used a delta_t of 1e-3 sec and I wrote out every 10th timestep. Then the long-time run used the same delta_t of 1e-3 sec but a writeInterval of 1000 timesteps (to have one data folder for each second). So far the code ran smoothly with little courant-no and continuity-errors. But the visualization showed highly unphysical behaviour that differed heavily from the runs with every 10th timestep written out. I did NOT change the delta_t, ONLY the writeInterval. Has anyone made a similar experience ? Any idea on what could cause that behaviour ? I guess my code overwrites a variable from the last timestep with a value that it reads from the last written-out folder. But apart from the createFields.H (which I definately only use once BEFORE the time-loop) I could not find any read-and-write command, at least in the code lines I did by myself. Does anyone know of OpenFOAM reading values from the last WRITTEN-OUT timestep rather than using the value from the actual last timestep ? I am using 1st order "Euler" as ddt-scheme and my controlDict looks as follows application myFreezeFoam; startFrom startTime; startTime 0; stopAt endTime; endTime 20; deltaT 0.001; writeControl timeStep; writeInterval 1000; purgeWrite 0; writeFormat ascii; writePrecision 6; writeCompression uncompressed; timeFormat general; timePrecision 6; runTimeModifiable no; adjustTimeStep no; maxCo 0.1; maxDeltaT 0.1; Thanks a lot for any suggestions and best regards, Chris |
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March 31, 2010, 08:39 |
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#2 |
Member
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Have you made sure that you don't have alpha1=0 in your visualising of the results? This can give strange results with phases.
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September 1, 2010, 19:42 |
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#3 | |
Member
Join Date: Nov 2009
Posts: 48
Rep Power: 17 |
Hi Chris,
Have you managed to solve your problem? Would you please explain how did you implement a solidification in interFoam. Is it possible to share your implementation? Thanks, Mehran Quote:
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Tags |
different results, interfoam, read error, read results, writeinterval |
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