Study on key design parameters of subway source heat pump system with capillary exchanger

Abstract

As an emerging subway waste heat utilization system, capillary network subway source heat pump system has high practical value. At present, there are many researches on capillary network heat exchanger, but little research has been done on the influencing factors and design optimization of the entire system. The orthogonal test method is used to determine the key design parameters affecting the subway source heat pump system. The multi-factor analysis method is used to optimize the system design. The results show that the key design parameters that affect the subway source heat pump system are the cooling and heating load ratio and the flow velocity in the capillary tube. Meanwhile in the future system design, the range of the cold-heat load ratio of the subway source heat pump system is between 1: 1.5 and 1: 2.5 and the flow velocity in the capillary tube is between 0.05 m/s and 0.09 m/s, which can be used as a reference for system design.