01.2020.313.320

A STUDY ON COOLING AND DEHUMIDIFICATION PROCESS OF A HEAT PUMP DRYING SYSTEM AT LOW TEMPERATURE

Author(s):
Hoang Ngoc Hieu†, Nguyen Van Dua‡, Vu Tuan Anh†& Trinh Quoc Dung†*

Affiliation(s):
†School of Heat Engineering and Refrigeration, Hanoi University of Science and Technology, No.1, Dai Co Viet Road, Hanoi 10000, Vietnam

‡Center for Micro Electronics and Information Technology, No. 25, Le Thanh Tong Street, Hanoi 10000, Vietnam

*Corresponding Author Email: dung.trinhquoc@hust.edu.vn

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

The heat pump drying technology at low temperature has been become widespread due to advantages of product’s quality in postharvest conditions, comparing to the conventional drying method. The efficiency of the heat pump dryer is predominately affected by cooling and dehumidification of moisture air moving through evaporator coils. Nevertheless, there is a lack of heat and mass transfer correlations for solving the problems. First attempts to fill the gaps of the heat and mass transfer problem are presented in this paper. A mathematical model is established from fundamental mass and energy equations. Numerical solutions of the model were solved by means of the Taylor series method. The results obtained in the study are the dehumidification of moist air through plain tube coils at the steady state. The other cases such as the dehumidification at finned-tube coils and dehumidification with air frost at the transient state will be shown in next papers.