Study On The Heat Transfer Performance Of Three-fluid Separate Type Heat Transfer Unit And Heat Exchanger Of Heat Pipe

There are many differences between the heat transfer with two-fluid and the heat transfer with three-fluid separate type heat transfer units of heat pipe. By using an analytical model of heat transfer units and heat exchanger of three-fluid separate type heat pipe, this paper presents the temperature transfer matrix equations to the kind of unit in the performance of the parallel- or counter-flow. Through the above analysis, we obtain the temperature transfer matrix equations to heat transfer units with the same heat exchanger surface. We obtain another kind of temperature transfer matrix equations to heat transfer units with different heat exchanger surface. These equations (2.15 ), (2.16), (2.18), (2.19) can be used in actual engineering checking design. Further more, by using the temperature transfer matrix equations to heat transfer units with the same heat exchanger surface, the correlation of the temperature efficiency?1,?2and some given parameters such as the heat capacity ratio M, the number of transfer units NTU, the overall coefficient of heat transfer ratio U, the ratio of the temperature difference at the inlet ?ti is obtained:Parallel-flow: Counter-flow:and the curves of the temperature efficiency are drawn out through the Matlab software. The temperature transfer matrix equations supply theory basis for academic calculation of engineering design, and the diagrams supply a shortcut way for calculating the outlet temperature of the heat exchanger.