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Hooman December 4, 2015 12:13
simple question on pressure boundary condition
 
At walls, were velocity is zero, is the normal pressure gradient always equal to zero or is that for incompressible flows?

FMDenaro December 4, 2015 12:56
Quote:
Originally Posted by Hooman (Post 576234)
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)

Hooman December 4, 2015 13:36
Is it set to zero in simulations?
In particular laminar flows?

FMDenaro December 4, 2015 13:58
Quote:
Originally Posted by Hooman (Post 576239)
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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