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SPH boundary & discontinuity correction terms

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Old   July 9, 2012, 05:47
Default SPH boundary & discontinuity correction terms
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Tarek
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I'm working on a CFD Matlab code using smoothing particle hydrodynamics (SPH) approach.

I have a great problem with the consistency at the boundaries & the discontinuities due to Shock waves. They make the code results totally wrong. I've tried to add terms for normalization & correction defined by (Liu) & (Chen) in the governing equations but I fail to get right answers.

Could anyone help me how to use the normalization & correction techniques in Navier-Stokes equations especially in discontinuities
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Old   July 27, 2012, 05:15
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Daniel Barcarolo
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What are you using to model your boundary conditions??
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Old   July 27, 2012, 05:26
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I used virtual exterior particles to mirror the fluid particles near the boundary. I didn't use boundary virtual particles.
Now I achieved the right results near the boundary. But in the wave discontinuity, I have an inaccuracy in result (represented in form of varying non-smooth results for a flow).
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Old   July 27, 2012, 05:36
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So you have used ghost particles...?

And are you also using Artificial Viscosity SPH?
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Old   July 27, 2012, 05:38
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Yes I used Monaghan Artificial Viscosity
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Old   July 27, 2012, 05:46
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As far as I know with AV SPH you will always encounter some problem with your results. If you want more quality and precision you should look for preciser variants of SPH like Riemann-SPH and delta-SPH...
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Old   July 27, 2012, 07:05
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OK I'll check & try that....many thanks
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