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Spacecraft liquid propulsion dose directly related to the life of the spacecraft and the mission of the spacecraft arrangements, so the spacecraft during the mission, as accurately as possible to estimate the amount of propellant tanks. On the other hand, rail filling system for liquid propellant under microgravity conditions, the amount of propellant tank independent detection, the good filling to grasp the opportunity to avoid the early end of life of the spacecraft. Due to the special nature of the micro-gravity environment, lead to many methods of measurement of the amount of propellant measurement accuracy is not high, for example, on the geostationary orbit satellite propellant measurement error of 3%, will lead to the estimation error of up to six months of their life. The papers main volume incentive law with a focus on analysis of the measurement principle and its influencing factors for the superiority of the method and ground test system for the preliminary design study. First, the system has been in the field of measurement methods, and disciplines basis method involves measuring principle of the various methods of measurement detail, summarizes the advantages and disadvantages of the various methods of measurement. Focus on the volume excitation method measuring principle, analysis of the non-adiabatic processes have a significant impact on the measurement and control equation, tank pressure and gas multi-component to these sources of error, and the error model reflects the ideal measurement control equation, the equation correct. At the same time, to discuss some of the factors that might have an impact on the measurement, and the existing technical conditions, to be able to achieve the technical indicators, estimated the accuracy of the method. Secondly, in the volume on the basis of the excitation method of the measurement principle, the energizing process gas inside the tank after excitation of the thermodynamic state of the simulation. From the energy of the gas quality and the equation of state to start the the incentive process gas heat and mass transfer model, static measurements and dynamic measurement system simulation, and simulation results are discussed. Explore and construct ground test system, the system including the tank, incentive device, the measurement system and data acquisition and processing system, which incentive device motor, crankshaft, eccentric, connecting rod, bellows and piston; measurement subsystem including pressure sensors, thermocouples and the corresponding measurement auxiliary circuit. Meanwhile, the specific process of measurement and data processing flow, and the proposed revision theory verification method. Then, analyze the impact excitation frequency vibration of factors, including the natural frequency of the tank structure, liquid sloshing frequency and collaborative resonance frequency of the bubbles, and put forward a method to estimate the minimum frequency. For special dynamic pressure measurement, analysis the luminal effect on the measurement results of the effect of corrective measures. Finally, the volume excitation method based on the existing, proposed some improvements, the purpose is to seek better measurement accuracy, applicability, easy to operate and convenient measurement method. In short, the paper theoretically system studied the volume excitation method of the tank liquid propulsion dose measurements under microgravity conditions, clear the measurement accuracy of the method can meet the requirements, making the measurement error of less than 1%, is a repeatable operation simple measurement means, and to explore the ground test program, provide a reference ground for the next test.
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