I am trying out LB for the first time and am looking at modeling flow within a region that has both porous and free flow conditions. I am just becoming familiar with the openLB library now, and have gone over a few introductory papers and texts on the LB method and am looking to set up the probabilistic bounceback condition for the porous material as described in several texts, including Ch. 9 of Sukop and Thorne (Lattice Boltzmann Modeling), I wondered if someone would be able to point me in the right direction as to
(1) whether I can use LB to model such as situation using openLB
(2) how this might be achieved.
Thanks in advance for any help that is offered!
Not sure what you mean by “probabilistic” bounceback, but the example cylinder 2d uses bounceback to represent an obstacle. Ive succesfully modified this code to model the open-porous interface, the only bit that requires modification is where to place the bouncaback nodes in iniGeometry.
Thanks for your response,
what I’m looking for is a way to implement the “Dardis and McCloskey” method. It is described Sukop and Thorne as follows:
“The method entrails specifying the porous medium by a ‘probabilistic’ bounce-back based on solid density. This provides a means of transcending the pore scale. Porosity can be varied arbitrarily so that assigning 0 to solids density, to fractures and macropores for example means that flow in those areas can still be simulated using the NS solutions… We can think of the method in comparison to the standard LBM approach for porous media where we can take a binary image of a medium that is segregated into pore space and solids; in the Dardis and McCloskey method, we can use a gray scale image that reflects the porosity”
I appreciate any suggestions on how to implement this.