Finite Element Analysis of Three-Fluid Heat Exchanger for Diesel Engine Exhaust Heat Recovery System

Abstract

In internal combustion engines, only a part of the fuel energy flow is transformed into power available at the crankshaft, while the most part of the fuel energy flow is lost as coolant, exhaust gases and other waste heat flows.The focus of this study is to evaluate the performance of three-fluid re-circulating type heat exchanger to recover energy from exhaust gas The cold fluid is re-circulated to enhance the recovery of heat from the exhaust gases. Finite element model of the heat exchanger is developed based on the detailed geometry and the specific working conditions and the effectiveness of the heat exchanger is computed. Non-Dimensional parameters are introduced which makes the analysis more versatile. The effectiveness is computed for different values of NTU, Heat capacity ratios, Overall heat transfer coefficient ratio between fluid channels and the inlet temperature.