Definition of flow condition at boundaries

[jaclu23]

Dear all,

I would like to further define the flow condition at the boundaries, e.g. in case of the given rectangular duct flow example.

• Is there a way to prescribe a certain inflow and outflow angle (or velocity vector)?
• Could a pressure difference between the inlet and outlet be used instead of a velocity?
• How could two opposite walls of the duct be implemented with a periodic boundary condition?

Presented BENCHMARK Case:

void main_setup() { // cylinder in rectangular duct
// ##### define simulation box size, viscosity and volume force ############
const float Re = 25000.0f;
const float D = 64.0f;
const float u = rsqrt(3.0f);
const float w = D;
const float h = 3.0f*D;
const float nu = units.nu_from_Re(Re, D, u);
const float f = units.f_from_u_rectangular_duct(w, D, 1.0f, nu, u)

Thanks for any help or advice!