Hi,
I'm trying to run simpl
Hi,
I'm trying to run simpleFoam on a test geometry at about M=0.05, laminar. I set up the case using FoamX with an inletOutlet boundary condition in the farfield, but since my flow is external (and there is only one hemispherical patch) this results in the solution converging to a quiescent state. If I change the 0/U boundary condition to fixedValue the problem becomes overdetermined and never converges. Is there a more appropriate boundary condition, or a method for specifying a velocitydriven external flow rather than a pressuredriven one? Thanks, Matt 
What did you choose as the inl
What did you choose as the inletValue for U?

Henry,
The internalField an
Henry,
The internalField and pressureInletOutletVelocity are both set to uniform (15 0 0). inletValue is only set for the turbulent fields, which I'm not using at present. Thanks, Matt 
Try using inletOutlet on U wit
Try using inletOutlet on U with an inletValue of (15 0 0) and zeroGradient on p.
pressureInletOutletVelocity should only be used in conjunction with fixedValue for p which I guess is not appropriate for your case. 
This results in very large num
This results in very large numbers of iterations for p (about 200 to produce a couple of orders of magnitude drop in the residual) and the solution becomes nonphysical after about 20 pseudotime steps.
As I understand it, using zeroGradient for all the boundaries of p (well, there is a symmetry plane, but that is the same thing) means that the matrix is underdetermined? 
There is a setReference to han
There is a setReference to handle this and adjustPhi is used to ensure the boundary fluxes obey continuity.

Thanks Henry, that seemed to w
Thanks Henry, that seemed to work. I'm still not getting full convergence, but have tracked down the problem to a poor quality element in the boundary region. Hopefully a better mesh will fix that.

You may be able to improve con
You may be able to improve convergence by selecting more stable/lowerorder schemes, in partricular you might find it useful to use the limited laplacian. However, improving the mesh is always preferable if possible.

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