Numerical Analysis of Heated Channel Flows by a Space-Marching Finite-Volume Technique

The design phase of devices involving many different flow phenomena requires efficient numerical simulations which, although based on some approximations, are able to manage complex flow modeling and fluid structure interaction. The attention of the present study is devoted to liquid rocket engine cooling channel flows, whose main characteristics to be taken into account are: high wall heat flux, of the order of 10MW/m2; high flow Reynolds number, of the order of 106 ÷ 107; fully three dimensional flow; near-critical thermodynamic conditions of the fluid; fluid decomposition reactions; coupling between flow and wall temperature evolution. The proposed approximation is to use parabolized Navier-Stokes equations. Parabolization is obtained by neglecting viscous derivatives in the space-marching direction and by considering the streamwise pressure gradient as a source term evaluated on the basis of the overall momentum balance. The algorithm is based on a finite volume approach, with a modified Roe’s approximate Riemann solver for a fluid governed by a generic equation of state. Validation of the approach is presented by comparison of channel flow results with full Navier-Stokes solutions and experimental data. Results show that the present approach is a practicable one for the study of cooling properties of real fluids in channels.