Transcritical CO2 heat pump dryer:: Part 1.: Mathematical model and simulation

In this study, a mathematical model and simulation code has been developed to investigate the performance of a transcritical CO2 heat pump dryer. The model takes into account detailed heat and mass transfer and pressure drop phenomena occurring in each component of the system. To take care of the variable heat transfer properties, the heat exchanger components were divided into several infinitesimal segments to examine the state, heat and mass balance and pressure drop for both refrigerant and air, and hence accurate results are expected. In Part 2 of the article, the model developed has been validated with experimental data and then the model was used to investigate effects of important operating parameters on the performance.