Aircraft Heat Exchanger-Condenser: Modeling the Features of Heat Transfer Process

Abstract

Thermal resistance of a radiator surface is formed in the course of a heat transfer at the expense of a heat-transfer coefficients ratio in hot and cold coolants. However, heat-transfer coefficients depend on a large number of factors. Factors which are of great importance for the heat exchanger condenser: change of heat-transfer coefficients on initial sites of heat exchange canals and existence of condensation and evaporation processes in coolants. These factors essentially affect on thermal parameters of a heat transfer process. In this paper the two dimensional numerical model of the compact heat exchanger with two-phase coolants in cold and hot paths is described. The model also considers change of heat-transfer coefficients on initial sites of heat exchange canals. The results of the numerical research of a heat transfer in the aircraft condenser are presented in this work. Comparison and the analysis of three combinations of thermal resistance options are executed: without initial sites and a heat-mass transfer, taking into account initial sites without a heat-mass transfer (dry air), taking into account initial sites and a heat-mass transfer in coolants.