Research on the Performance on Frost-Free Air Source Heat Pump with Waste Heat Desorption

Abstract

For the novel frost-free air source heat pump system (FASHP), the compressor waste heat is used to assist desorption for the desiccant on the surface of the desiccant coated heat exchange (DCHE). It can promote the desorption efficiency of the DCHE in the FASHP and reduce the energy loss, which means the improvement of the stability and performance. In this paper, a DCHE model is established, and its accuracy is verified through experimental data. The model is then used to analyze the effect of working conditions and structural parameters on the adsorption rate, desorption rate, heat exchange and proportion of latent heat in the adsorption and desorption processes. The results show that the latent heat ratio is higher, the heat exchange of the DCHE is lower and the system performance is better when the temperature of the analytical circulating air increases and the velocity decreases to 25 °C/0.5 m/s. In addition, the performance is greatly affected by the fin length and width. With the increase of parameters, the heat exchange and proportion of latent heat can be increased to 115.9 J and 69.0%.