Remove species through a Wall

PK

Hi,

I am trying to simulate the problem of a capture of a species in a 2 species flow (for exemple S1 is the main specie and S2 is the second one). It is a 2D problem and the flow is the one around a cylinder defined as a wall (for example). This cylinder is the source of the capture of the S2. have several questions (even after going through some related questions in this Forum). -I guess that I have to use the user DEFINE_SOURCE macro and write my own UDF -WHen I am removing S2, shal also remove the coresponding momentum (opposite problem when adding a specie in a cell) : if so how should it be done excatly ?. -What about if this capture concerns not only the neighboring cells but also a depth of cells around this cylinder ; how to access to those cells ?. Thanks for your help