Experimental investigation of high-temperature heating in open-loop air cycle heat pump system utilizing compressed gas waste energy recovery

Recycling waste energy from compressed gases has consistently been a focal point in the field of energy conservation. This paper presents a novel open -loop air cycle heat pump system designed to recover waste energy from compressed gases. The system maintains stable operation and provide hot water above 80 degrees C even under extreme ambient temperatures (below -30 degrees C), thereby catering to diverse heating needs across a wide temperature spectrum. Experimental results show that, when the ambient temperature varies from 10 degrees C to -20 degrees C, the heating capacity and water temperature difference between inlet and outlet only decrease by 4.82% and 4.99% respectively, suggesting negligible impact. However, when water flow rate varies from 4 m 3 /h to 10 m 3 /h, the heating capacity marginally increases by 3.35% while the water temperature difference between inlet and outlet significantly decreases by 141.95%. Continuous increase of inlet water temperature T w, in at 0.40 degrees C & sdot; min - 1 results in an initial 10% decrease of heating capacity, following which the system automatically adjusts to another stable operational state of around 50 kW heating capacity. This transition has minimal effect on the water temperature difference between inlet and outlet and temperature rise rate of outlet water temperature. The expansion work recovery efficiency of turbine -compressor coupled module is approximately 90%.