Design And Optimization Of The Microgravity Experimental System For Coal Combustion Used For SJ-10 Satellite

The main energy of China is coal and other energies are auxiliary. Coal has high combustion efficiency and low discharge rate of pollution, which has important significance to energy conservation and emission reduction of our country. For a long time, scholars have made a large quantity of research on the combustion process of coal. Most of the research was made with earth gravity. While researching it on the ground, it was difficult to eliminate the influence of gravity and buoyancy force on combustion process. Many scientific parameters could not be accurately measured, which influenced our profound and accurate understanding on the mechanism of coal combustion. Some coal combustion experiments were operated in transient drop. It is limited by micro-gravity time, the number of kinds of experimental samples and the time of combustion. There is no doubt that the perfect microgravity environment of outer space can offer ideal platform for the research on the mechanism of combustion of coal. It contributes to understanding the combustion process of coal, raising combustion rate of coal, achieving energy conservation and emission reduction and decreasing fog and haze.The outer-space coal combustion project of “No.10 Practice” satellite offers approach for us to research the combustion process of coal without the influence of gravity. Based on this project, this paper makes relevant design and research aiming at microgravity experiment.Firstly, this paper summarizes the domestic and foreign research on the coal combustion experiments in microgravity. Based on previous research of scholars and aiming at project “No.10 Practice”, this paper designs scheme, analyzes risks and verifies design for microgravity experiment system. Secondly, it utilizes value simulation method to simulate and optimize the thermal insulation properties of heating furnace of microgravity experiment system; reasonable suggestions are given. Through simulating the heating process of heating furnace, this paper ascertains the heating power in outer-space experiment. The result indicates that it can greatly shorten heating time and decrease the total energy consumption to raise heating power in acceptable largest power. It also simulates the homogenization process of coal powder without gravity, preliminarily researches the homogenization process of coal powder without gravity and offers basis to the phenomena in outer-space experiment and the time of homogenization. The simulation indicates that homogenization time of 20 minutes contributes to getting good coal particle group and therefore contributes to operating good flame spread experiment without gravity. At last, it makes thermogravimetric analysis on the experimental samples and utilizes outer-space equipment to operate ground matching experiment to coal particle samples. Through the experiment, we can speculate coal particles are difficult to burn in the natural convection without microgravity. The observable phenomenon may be partial oxidation. At the same time, drop tower of mechanics institution of Chinese Academy of Sciences is used to operate combustion experiment of coal particles. The experiment result indicates that heat transfer and substance transmission are two factors of microgravity influencing the combustion of coal particles and substance transmission is the main factor which influences combustion process.