Present study focuses on analysis of thermal performance of wickless heat pipe heat exchanger (WHPHE) using DI water as a working fluid for recovery of heat from hot gas at simulated engine exhaust conditions. WHPHE used in this study is constructed using copper tube of 12 mm internal diameter and 2 mm thickness with evaporator and condenser sections of length 150 mm each and central adiabatic section of length 50 mm. Bench scale experimental setup was developed to analyze thermal performance of WHPHE using De-Ionized (DI) water as a working fluid at various hot gas inlet temperature (~134, 205 and 280 °C) and flow rates (Re 2500 to 4000) using cold fluid as air at different flow rates (12, 18, 24 and 30 lpm) and inlet average temperature of 32 °C at 1.2 bar pressure.

Theoretical analysis of WHPHE is carried out using Ε-NTU method to predict the performance parameters at all operating range of experimental conditions. Comparison of experimental results with theoretical predictions shows that theoretical analysis under predicts the experimental results by an amount of 5 to 18.8% for majority of the experimental conditions and over predicts by 1.5 to 18% for few of the conditions.