Experimental investigation of steady state heat transfer phenomenon in Pontiac G6 vehicle exhaust system
Specifically, this work describes the characterization of the exhaust gas heat transfer through steady state gas and surface temperature measurement on chassis dynamometer. Experiment has been performed on instrumented prototype research vehicle following the road load conditions. This was accomplished by applying predefined loads and grades to the load cell of the chassis dynamometer. The exhaust gases have been routed carefully outside of the laboratory to ensure no temperature changes in the test cell. The data contained in this present work include temperature measurements at 48 locations starting from exhaust manifold to the tail pipe of the exhaust system. This temperature data provides a through insight of the heat transfer characteristics through the exhaust system by different modes including conduction, convection and radiation. The computed temperature data is employed to calibrate the 3D CFD simulation results to eliminate the prototype phase and aid in vehicle development shrinking time. Interior and exterior Nusselt numbers were computed with the acquired exhaust thermal data and it correlated well with the Reynolds number. Nusselt number calculation based on the ideal correlation of Sieder-Tate for fully developed flow in the pipe was found to be less than the measured Nusselt number. This is attributed to the exhaust pulsatile flow and entrance effects. To compensate this Convective Augmentation Factor (CAF) was introduced and defined as the ratio of the measured Nusselt number to the ideal Nusselt number Sieder-Tate correlation. The CAF values correlated well with the interior Reynolds number. ^
Engineering, Automotive|Engineering, Mechanical
Sainoju Korremla, Shiva K, "Experimental investigation of steady state heat transfer phenomenon in Pontiac G6 vehicle exhaust system" (2007). ETD Collection for University of Texas, El Paso. AAI1449760.