Study on the Dehumidification and Heat Transfer Performance of Heat Pump Drying Systems

This study investigates the dehumidification and heat transfer performance of heat pump drying systems by combining numerical simulation with experimental methods. An air condensation model was developed for the air-side of the heat pump evaporator, and a heat pump system experimental bench with controllable airspeed, temperature and humidity was built. The average absolute percentage errors between simulation and experimental results for the air temperature difference and dehumidification of air flowing through the evaporator were 2.9% and 5.01%, respectively, which verified the accuracy of the model. Based on experimental results, this study further discusses the simulation boundary conditions of the condensation model under different air conditions. The combined simulation and experimental findings reveal that under constant temperature and humidity conditions, the air temperature difference and dehumidification capacity across the evaporator exhibit similar trends and stage characteristics. Under constant air volume and humidity conditions, the air temperature difference across the evaporator decreases with increasing inlet temperature, while the dehumidification capacity shows the opposite trend. The conclusions of this research provide a reference for developing more accurate dehumidification and heat transfer models for heat pump drying systems.