Abstract: The thermal propellant gauging system (TPGS) method is a method for measuring the residual amount of satellite propellant with active heat source input. It calculates the residual amount of propellant according to the temperature variation data of the measuring point when the tank heated by a specific power heating plate, and the measuring point is attached on the tank wall. In order to obtain an accurate thermal analysis model based on the gas-liquid distribution characteristics of plate tank in orbit in the microgravity environment, numerical simulation of the TPGS method is carried out with computational fluid dynamics (CFD) method to analyze the influence of different acceleration conditions, filling ratio and measuring point position on the accuracy of the TPGS method. The results show that the propellant climbs up along the deflector in the microgravity condition, and the wall area covered by the fuels larger, which results in the temperature variation in microgravity condition is obvious different compared with ground condition. It is found that, in the microgravity condition, when the measuring points are distributed away from the heat source, the temperature resolution of the measuring points is higher, and the measurement accuracy of the TPGS method is higher.

Key words: thermal propellant gauging system method, microgravity, vane type surface tension tank, propellant, residual propellant gauging method