Use of Subdomains for Inverse Problems in Branching Flow Passages

Abstract

For inverse problems in complex flow passages, a calculation procedure based on multizone Navier-Stokes method was developed. A heuristic approach was employed to derive wall shape corrections from the wall pressure error. Only two subdomains sharing a row of control volumes were used in the present work. The grid work in the common region was identical for both subdomains. The flow solver, inverse calculation procedure, multizone Navier-Stokes method and subdomain inverse calculation procedure were validated independently against experimental data or numerical predictions. The subdomain inverse calculation method was applied to determine the wall shape of the main duct of a branching flow passage. This main duct was to minimize the pressure gradient downstream of the sidebranch. Inverse calculations resulted in a range of wall shapes with wall pressure distribution approaching the design (prescribed) wall pressure distribution. The present approach was illustrated for laminar, incompressible flows in branching passages. However, the method presented is flexible and can be extended for inverse turbulent flow calculations in multiply connected domains.