[QBeast]

Hi guys,

I'm modelling a doubly periodic channel flow of rectangular section, to summerize, it's:

orientation:
x streamwise (mean flow direction-set to periodic)
y wall normal (non-slip Boundary condition)
z spanwise (periodic)

flow direction: x
x and z periodic
and non-slip condition at the upper and bottom wall,

I need some help to write an UDF to impose a spanwise velocity forcing wave travelling downstream which is likely to be coordinate and time dependent like A(z).Sin(Kx.x+Ky.y).Sin(w.t), on the whole domain and update every timestep, I've been looking around but found a 3 yers old thread dealing with roughly the same thing (tank with cg motion).

I've already worte UDFs generating waves at the inlet but did that only on Velocity_inlet boundary condition, Is there a way to perform the same thing to a whole domain ie every single node will have its spanwise velocity forcing contribution changing every timestep.

I'm wondering if the DEFINE_SOURCE macro is an option for pointing out every cell and adding/updating y momentum?
found this on the forum

http://www.cfd-online.com/Forums/flu...urce-term.html

thanks in advance, best regards.