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Pressure boundary conditions
Hi all,
First I thought that if you have a boundary condition which imposes pressure only, the velocity at that point is taken as being the same as the neighbouring cell. In fact it imposes grad(v)*n = 0 near to the pressure (outflow) boundary, but I supposed that for many flows, it's not a problem. Now I wonder if solving the unknowns for boundary conditions would make the system a little less stiff. The problem is: I already have 3 equations (Navier Stokes X and Y and continuity) for each cell, as well as 3 unknowns (X and Y velocities and P). I cannot solve it if I have additional unknowns for boundary conditions. The problem for boundary conditions imposing velocity only is the same. Some people told me to read Versteeg and Malalasekera, but I didn't find exactly what I search. Any idea ? Thanx in advance |

Re: Pressure boundary conditions
for pressure b.c----
on the outflow---p=0 and any other plane normal gradient of p is =0 try it. |

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