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uncorrect interFoam forces results

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Old   January 28, 2020, 11:33
Default uncorrect interFoam forces results
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Kil
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Hello everyone!
I'm new OpenFOAM user. I recently calculated the ship's resistance using the interFoam solver. To my great regret, it wasn't possible to get correct results.
The projection of pressure forces on the ship's hull in the X-direction has too large a spread (see the figure). Tell me please, what this may be caused by?
(I'm used OpenFoam Version 7 and DTCHull tutorial)

P.S. Sorry for my bad English
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Old   January 28, 2020, 12:09
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The tutorial uses the localEuler time scheme to compute a steady solution, so you will not see "correct" results until the simulation converges (i.e. you should only look at final result -- and even then it looks like you should run it out longer).

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Old   January 29, 2020, 12:51
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Quote:
Originally Posted by clapointe View Post
The tutorial uses the localEuler time scheme to compute a steady solution, so you will not see "correct" results until the simulation converges (i.e. you should only look at final result -- and even then it looks like you should run it out longer).

Caelan
Could you help me to understand why, it was possible to calculate the pressure forces in the DTCHull tutorial with enough accuracy (see figure 1)?
Do I need to increase the number of iterations (i.e. reduce the time step) or do I need to improve the quality of the mesh (see figure 2)?
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Old   January 29, 2020, 16:09
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I have never run the tutorial; I am just trying to explain why you might be seeing the behavior you are seeing. Accuracy is always relative to the application, and I cannot comment on what is good enough for this case -- perhaps someone else with more experience could be of more help. Running it out longer or making the mesh better are both possible things to try.

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Old   January 30, 2020, 12:23
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Ok. Thanks a lot!
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Old   January 30, 2020, 12:27
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Has anyone ever used DTCHull tutorial and intterFoam solver tell me please how I can get accurate results!
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Old   October 10, 2020, 13:14
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As time goes on, there are more and more questions, but there are no answers to them....
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