A criterial analysis of the effectiveness of air-to-air heat exchangers with periodic change of airflow direction

Abstract The physico-mathematical model of the regenerative heat exchanger with periodic changes of air flow direction has been developed. The model takes into account phase transitions both on the surface of air channels of heat exchange matrix and directly in the airflow. In this paper, the results of the influence of parameter groups on the heat exchanger effectiveness are generalized. Such generalization is reached by identifying the governing dimensionless groups in the system of equations. The analysis using the generalized parameters allows considerably simplifying the study of processes with a large number of parameters. In addition, the influence of air humidity and temperature on the sensible and latent effectiveness of the heat exchanger has been analyzed. Computations enable determining the heat exchange matrix material that is the most suitable in terms of its thermophysical properties.