Operating Characteristics of a Pump-driven Loop Heat Pipe Energy Recovery Device

A pump-driven loop heat pipe energy recovery device was proposed to reduce the energy consumption of fresh air handling in public buildings through energy recovery from exhaust air. An experimental setup was built to investigate the energy recovery device operating characteristics for 3 working fluids under 8 working conditions. The influence of working fluid and working condition on heat transfer rate, temperature efficiency and coefficient of performance (COP) of the device was studied. Results show that the device can meet the energy recovery requirements in public buildings with obvious energy saving. The heat transfer rate and COP increase with the temperature difference between indoor and outdoor air while the temperature efficiency decreases. The COP under the summer and winter conditions can reach up to 11.07 and 23.82, respectively. The performance of the device using R32 as working fluid is better than that of R22 and R152a.