Rob,nthank you for the reply. I will take a look and try to set up the motion using layering and then will post here in case if I succeed or have any further question. nRegarding Flat Interface assumption - in the end I am looking to account for curvature (either to achieve dynamically deflecting interface during the solution or with pre-set shape of the interface). However at this point I am assuming just the flat wall motion, to gradually gain better understanding of the moving mesh capabilities.n