Characteristics of Frosting according to Refrigerant Flow Direction and Tube Arrangement on Heat Exchanger

摘要

In order to investigate characteristics of frost formation according to refrigerant flow types and tube arrangements on plate fin-tube heat exchanger, both inline and staggered tube arrangement heat exchangers were operated under cross counter flow and cross parallel flow conditions. As a result of frost experiments, the cross counter flow heat exchanger showed more uniform frost formation than the cross parallel flow heat exchanger in each rows. In early of the frost experiment, the cross counter flow heat exchanger which had staggered tube arrangement showed more active heat transfer than the cross parallel flow heat exchanger. After middle of the experiments, differences of heat transfer rate between the heat exchangers were decreased. However, overall heat transfer rate during the experiments was greatest in staggered tube arrangement under counter flow condition.