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Free surface flow modelling using SPH with periodic boundary condition

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Old   February 14, 2018, 21:12
Smile Free surface flow modelling using SPH with periodic boundary condition
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Hi all,
I am trying to simulate a free surface flow over an inclined surface with explicit incompressible SPH and periodic boundary conditions in x-direction. The flow is driven by gravity in x direction (gsin(theta)). But I can't get the analytical solution and the velocity keeps increasing until it converges to a value which is not what I expect (as you can see in the figure). Does any of you have any idea what could cause this problem?
Thanks a lot
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Old   February 15, 2018, 00:33
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I don't know how you set up your case. Inclined and periodical b.c. does not fit. Do you use inclined gravity?

Periodic b.c. couples the outlet with the inlet. You have to ensure, that from physics both sides are real equal. If the outlet transforms energy to the inlet, your velocity will increase until blowup.
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Old   February 15, 2018, 00:42
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Thank you for your response.
What I did was I set up a horizontal domain and inserted a body force in horizontal direction to account for the gravity (g*sin(theta)).
Best regards
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