[mtgoncalves]

I am simulating incompressible laminar external flows in 2D (e.g. flow past cylinder, airfoil, etc.). For this I am using a hybrid solver consisting of pimpleFoam coupled to another non-OpenFOAM solver. I use pimpleFoam only to simulate the near-body flow. The meshes I use are small: the numerical boundary is close to the solid body. Hence, the boundary conditions I need to impose for U and p are unsteady and non-uniform.

With the external solver I can compute the velocity, velocity gradient, pressure and pressure gradient at the coordinates of the face centers at the boundary of the mesh used by pimpleFoam. To impose these conditions I have modified the inletOutlet and outletInlet boundary conditions such that I can change at each time step the:

• refValue for velocity at inlet faces
• refGradient for pressure at inlet faces
• refGradient for velocity at outlet faces
• refValue for pressure at outlet faces

The problem I am facing now is that for the gradients I am now only imposing the normal component. Because I can get everything from the external solver I would also like to impose the tangential component of the gradients.

So my question is: what do I need to modify in inletOutlet and outletInlet such that I can impose the actual gradients and not merely their normal component.

ps: If it makes more sense to start development from a different boundary condition (e.g. mixed or directionMixed) please tell me.

[thabuis]

If you solve your problem, I would be interested in knowing the answer

[HPE]

if there is a code example, we may try to work on that.