Performance Enhancement of Heat Pumps Through Selection of Refrigerants R134A and R410A in Shell-and-Tube Condenser

Abstract

This experimental study evaluates the performance of a Shell-and-Tube heat exchanger using refrigerants R134A and R410A, emphasizing the heat transfer rate and Log Mean Temperature Difference (LMTD). The experiments were conducted using a heat pump system featuring a condenser area of 0.785 m², at varying water mass flow rates (0.08 to 0.1 kg/s). Results indicated that both refrigerants exhibited increased heat transfer rates and LMTD values with rising mass flow rates. Specifically, R410A showed a heat transfer rate increase from approximately 10.46 kW to 11.32 kW (6.7%), while R134A demonstrated an increase from 9.71 kW to 10.53 kW (5.1%). LMTD values increased from 25.67°C to 27.45°C for R410A (6.7%) and from 24.17°C to 25.72°C for R134A (7.1%). R410A consistently outperformed R134A across all tested conditions, achieving maximum differences of 0.8 kW in heat transfer and 1.5°C in LMTD at the highest mass flow rate (0.1 kg/s). Thus, R410A is recommended for superior performance in Shell-and-Tube condenser applications.