Re: Venturi3d example
the point of view in this case is that solid is simply represented by a porosity of 0 and fluid by a porosity of 1. In the phase tranistion region there are values in between 0 and 1, to allow for a smooth transition and thereby increase stability. For more information see
Another appraoch could be the paritally saturated cells method (PSM), described e.g. in the book “The Lattice Boltzmann Method – Principles and Paractice” by Krüger et al. This however is currently not implemented in OpenLB.