slip BC using boolean mask


I am going to simulate 3D rarefied gas flow through a micro-porous medium. The geometry
of a porous medium is given by boolean mask (0-gas nodes, 2-solid nodes, 1-intermediate nodes).
Now I need to implement the slip BC on the intermediate nodes.
I have tried to do it using

boundaryCondition->addVelocityBoundary1P( bb, lattice, boundary::freeslip );

were bb is:

    DotList3D bb;
	for (plint iX=0; iX<nx; ++iX) {
	    for (plint iY=0; iY<ny; ++iY) {
	    for (plint iZ=0; iZ<nz; ++iZ) {
	        if ( geometry(iX,iY,iZ) == 1 ) {

but I have failed.

Any help is highly appreciated.

best regards


The freeslip boundary only works at the domain boundaries.