Dear ff3d Users,
I would like to solve the Stokes problem around an obstacle, which imposes
a non-uniform slip boundary conditions on its surface.
The slip velocity is determined by the gradient of a solute concentration, "RHO"
around the obstacle. More precisely, by the projection of the gradient along the
obstacle surface:
V_{slip} = grad_{tangent}(RHO) = grad(RHO) - n.(n.grad(RHO))
where "n" is the unit normal vector on the obstacle surface.
Does it make any sense to define this slip boundary conditions as I did in the
line 11, below? Or may be the tangential gradient is already implemented in
ff3d?
With the best regards,
M. Tasinkevych.
/**************************************************************************************
1 mesh M = read(medit,"MESH.mesh");
2 function RHO = read(medit,"
concentration.bb",M);
3
4 solve(u1,u2,u3,p) in M
5 {
6 test(U1,U2,U3,P)
7 int ( ...... ) = 0;
8
9 // slip boundary condition of obstacle
10
11
u1 = dx(RHO) - nx*(nx*dx(RHO) +ny*dy(RHO)+nz*dz(RHO) ) on obstacle ;12 " and similar equations on u2 and u3"
13}
//**************************************************************************************