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Setup of flat plate problem for laminar layer

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Old   August 7, 2011, 07:47
Default Setup of flat plate problem for laminar layer
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Could someone to tell me what boundary conditions must be put at flat plate problem for laminar boundary layer?

I have solved the problem with below boundary conditions but i see a problem (incresment of density) at left lower corner at which connect the left boundary with symmetry plane.

Left boundary: specify: pressure, all velocities
upper boundary: same of left
right boundary: all gradients are zero
left lower (x<0): symmetry
right lower (x>0): viscous wall
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Old   August 8, 2011, 19:43
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sounds like you are overspecifying the lower left boundary, or you are having accuracy issues. a rise in density at that point means that you have created a stagnation point there, which is due to your flow coming from an Euler (symmetry wall) to a Navier Stokes (viscous) wall!
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Old   August 9, 2011, 03:25
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No, i do not refer at stagnation point at connection of symmetry and wall but at start of symmetry plane (at left lower corner of domain).
As i see , some information of domain arrive here and after increse the density except of reflection of information.
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Old   August 9, 2011, 17:37
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Quote:
Originally Posted by panou View Post
No, i do not refer at stagnation point at connection of symmetry and wall but at start of symmetry plane (at left lower corner of domain).
As i see , some information of domain arrive here and after increse the density except of reflection of information.

Well, still, if you get a stagnation point (an unphysical one), you should check how the code sets the boundary conditions. Are they set twice at the point? Maybe there's a conflict, it sounds like you are over-constraining the flow there, e.g. what happens to the density in the symmetry BC routine?
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