Unsteady Simulation of Conjugate Heat Transfers with Exhaust Pulsating Temperature for Vehicle Thermal Management

Abstract

Unsteady simulation of heat transfers for vehicle exhaust system plays an important role in vehicle development process. Based on STAR-CD software, a sedan exhaust system model, which includes the exhaust gas, the exhaust pipes and aftertreatment devices, was established. In this model, the complicated boundary conditions between fluid and solid, which need to be specified in the non-coupled models, are now part of the solution and do not need to be specified. A three-dimensional unsteady simulation was undertaken for the heat transfer characteristics of vehicle exhaust system. The heat transfer characteristics with the periodic pulsating exhaust temperature were obtained and analyzed, and the unsteady mean value were compared with the steady results, and the discipline between the steady heat transfer characteristics and the periodic pulsating exhaust temperature were found.