I’m presently working on the implementation of Zou/He BC for a D3Q19 code, and I’m running into some problems. I would like to ask, if someone could provide me with some simple example code (C/C++/Mathlab) for a 3D implementation.
I have a sucessfully implemented the BC, and running a simple test (Dirichlet inlet, Neumann outlet, remaining Periodic) I got the correct velocities at the inlet, correct pressure/density at outlet, but in the bulk I have a small constant deviation in velocity, and I don’t see why. I assume, that there is something wrong either with the BC or with the workflow. I’ve already made benchmarks with simple 2D cases, which were really good, thus I think the main structure/code should be ok.
I’m using the slightly different implementation of Zou/He BC from ?[ Hecht M and Harting J (2010) Implementation of on-site velocity boundary conditions for D3Q19 lattice Boltzmann simulations. Journal of Statistical Mechanics…], wich - up to now - was clear to me, but presently I’m really confused!
Please, could anyone give me some advices?