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Old   December 4, 2015, 13:13
Default simple question on pressure boundary condition
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At walls, were velocity is zero, is the normal pressure gradient always equal to zero or is that for incompressible flows?
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Old   December 4, 2015, 13:56
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Originally Posted by Hooman View Post
At walls, were velocity is zero, is the normal pressure gradient always equal to zero or is that for incompressible flows?
the normal component of the pressure gradient evalated at the wall is never exactly zero ... the Prandtl theory for the BL shows it is of order (1/Re)
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Old   December 4, 2015, 14:36
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Is it set to zero in simulations?
In particular laminar flows?
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Old   December 4, 2015, 14:58
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Is it set to zero in simulations?
In particular laminar flows?
setting dp/dn = 0 is an approximation, it would imply that

dvn/dt = n.(diffusion - convection)
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