Calculation of heat transfer characteristics of a finned wall

The reliability and resource of the radio-electronic equipment of the spacecraft is increased by ensuring optimal temperature conditions. Thermal control systems maintain the set temperature mode and heat removal from the onboard equipment to the surrounding space. Finned heat exchangers are an important element of the design of thermal control systems, which allows intensifying the heat transfer process. The calculation of the characteristics of finned heat exchangers must be carried out taking into account their parameters and the physical properties of the heat transfer agent. The organic liquid LZ-TK-2, which has a very low freezing point and other useful performance characteristics, is considered as a heat transfer agent. The dependences of the local heat transfer coefficient of the LZ-TK-2 heat transfer agent on the wall temperature are calculated using criteria equations. Based on the numerical solution of the two-dimensional problem of thermal conductivity, the temperature fields in finned walls of various configurations are determined. Calculations of the heat transfer coefficient of the finned wall of the heat exchanger were made in two model approximations, the error of using a simplified approximation that does not take into account the temperature dependence of the local heat transfer coefficient was determined.