A simplified model for correcting the heating capacity of air source heat pumps in high-altitude plateau areas

Abstract

The performance of air source heat pumps (ASHPs) is typically evaluated in plain areas, leaving limited insight into their performance in high-altitude plateau areas. To address this, a simplified fitting model is proposed to correct ASHP heating capacity in plateau areas. The structure of the fitting model is deduced based on physical principles. Then we regress the model on simulation data calculated by a complex model from previous study. Finally, the fitting model is validated by both simulation data and field test data from four ASHP projects comprehensively. Utilizing the fitting model, the influence of outdoor temperature and altitudes on the correction factor are fully discussed. Results show that the proposed fitting model is easy to facilitate in practical engineering. Only three sets of experiments are required to determine the constant coefficients of the fitting model, thus eliminating the necessity of establishing a complex calculation model for ASHP systems. The heating capacity and correction factors of ASHPs in the plateau areas can be accurately calculated by the proposed fitting model. The maximum error is around 0.5 % compared with the model in a previous study. When compared with the monitored data from real projects, approximately 80 %∼85 % of the points fall within the ±20 % error line. For every 1000 m increase in altitude, the heating capacity decreases by approximately 3.9 %–5.1 %. The proposed fitting model offers simplicity and convenience for designing ASHP heating systems in high-altitude plateau areas.