Satellite Thermal Analysis In Various Environment And Thermal Control Optimization Of Single Machine

With the development of space science and technology, human exploration of space is more and more. Especially since entering the 21 st century, countries around the world are scrambling to develop the aerospace industry, and many ground-breaking progress has also been made in China at the same time. Space technology does not only reflect a country’s level of science and technology, but also has brought a lot of convenience of aspects of daily life to all. So the development of the aerospace industry is essential, and one of the key initiatives is to do thermal analysis of satellite. The probability of the damage to satellites due to the failure of thermal control system is very high, which have leaded to the failure of satellite launch in United States, Canada, Japan and other countries. According to shortcomings of the traditional thermal control system,many scholars have studied that and proposed some optimization scheme, but that does not fully meet the development of the satellite. Therefore, this paper will study the thermal analysis of satellites and optimization scheme of the temperature of single machine, when satellites fly in orbit under variable conditions.This paper has studied the thermal analysis of a hypothetical satellite model by using Monte Carlo method and finite element method to calculate the satellite external heat flux and temperature distribution of the entire satellite, respectively. For the problem of temperature distribution of the entire satellite, this paper has presented a heat control program of liquid metal in microchannel, and has done the similarity analysis and dimensional analysis of it. Then, the paper has discussed the thermal control system of liquid metal in microchannel, starting from the performance of electromagnetic pump and the shape of microchannel, and optimized the calculation of the temperature gradient, which is too large, of the partial single machine and large-scale single machines by applying the optimization system to the satellite in different postures, Finally, this paper analyzes the impact of various factors on single machine temperature, and sensitivity analysis has been carried out.The numerical results show that the heat flux of the outer surface of satellite is greatly influenced by posture, that is obviously periodical; The temperature of single machine within the satellite is influenced by its own power, the next single machine, the temperature of the adjacent structural plates and external heat flux; Increasing the power of electromagnetic pump enhances the effect of heat exchanger of the micro-channel heat exchanger; when the fluid rate is equal, the effect of heat exchanger of the rectangle micro-channel heat exchanger is the best in a variety of shapes; Liquid metal in microchannel heat exchanger system can effectively achieve the control of single machines within the satellite and local temperature gradient; The emissivity of coating on single machines has the greatest impact on the temperature of single machines.