Numerical Simulation Study On The Mechanics Of The Enhanced Heat Transfer In Compound Flow Channels

The plate heat exchanger has become the most widely used industrial equipment because of its low-cost, higher heat transfer efficiency and flexibility. Domestic and foreign researchers have done many studies on fluid flow and heat transfer characteristics, and discovered that shortcomings exist in the plate heat exchanger such as large resistance losses and low heat-exchange efficiency. Therefore, in order to reduce the pressure drop and improve heat-exchange efficiency, this paper presented a new structure of the corrugated plate heat exchanger--plate heat exchanger with compound corrugation flow channels.In this paper, the heat transfer enhancement mechanism of the plate heat exchanger is studied by means of numerical simulation. The main contents are as follows:(1) The heat exchanger performance of compound channels, chevron channels and mixed channels were compared and the simulation results showed as follows:Compared with chevron channels with small corrugation inclination angle, the heat transfer coefficient of the composite channel was increased by 14%, in other words, the heat transfer efficiency of compound channels were improved.Compared with chevron channels with large corrugation inclination angle, the pressure drop of the compound channel was decreased by 20%. An improved resistance performance of the compound channel is proven.Compared with mixed channels, the heat transfer coefficient of the compound channel was increased by 8%, which shows that compound channels could improve the heat transfer efficiency and have a positive effect on the heat transfer enhancement.(2) By studying on the characteristics and the heat transfer of the flow channels of three kinds of plate array by numerical simulation, when place the plate according to the opposite direction of the corrugated inclined and the upper and lower side of compound flow channel has the same corrugation inclination angle, the heat transfer of compound corrugation flow channels is enhanced, and the ratio of pressure drop and heat transfer coefficientheart increased.(3) In order to study how corrugated inclination angle affects heat transfer coefficient and pressure drop of a plate heat exchanger with compound flow channels, a lot of experiments have been made. An experimental plan was made based on 2 factors, the large corrugated indination angle ?2 and the small corrugated indination angle ?1. By simulating the heat transfer processes, the performance parameters were got. And the large corrugated inclination angle has a significant effect on the performance parameters of compound flow channels. And the heat transfer coefficient increases as the corrugation inclination angle inerease.