Numerical Analysis On Cryogenic Propellant Tank’s Active And Passive Thermal Protection System On Orbit

The cryogenic propellant has some advantages of non-toxic and high specific impulse which become a viewpoint in the research field of power of Astronautics. When the spacecraft is on orbit (especially the deep-space exploration), the cryogenic propellant is evaporable which produces an effect on the power system. However, an efficient thermal protection system can reduce the evaporation of the cryogenic propellant in. order to make the power system to maintain good condition. So it is very important to use a practical active and passive thermal protection system to control the evaporation.This article analyzes some active and passive thermal protection systems which can meet the long-term working needs on orbit from the perspective of engineering applications. This study uses the software Sinda/Fluint and is preceded by the ways of theoretical analysis and numerical simulation about flight attitudes, orbit conditions, thermal protection systems and phase transition in cryogenic propellant tank to get the conclusion about the factors of propellant tank’s internal temperature field and propellant evaporation rate change rule.Firstly, the numerical simulation draws the general conclusions on propellant tank’s internal temperature field and propellant evaporation by changing the different flight attitudes(including 8 attitudes such as attitude towards the sun/earth and spinning attitude ) as well as the two different orbit conditions (synchronous satellite orbit and elliptical orbit).Secondly, the numerical draws the general conclusions on propellant tank’s internal temperature field and propellant evaporation by changing the passive thermal protection systems (including 8 kinds of passive thermal protection materials, 6 kinds of structural materials and MLI).At last, the numerical draws the general conclusions on propellant evaporation by changing the active thermal protection systems (including different orbit conditions, flight attitudes and several typical passive thermal protection systems). This study simulates the work of Thermodynamic Venting System and refrigeration system to study of the evaporation of the cryogenic propellant in different cases in order to research on the improvement of the internal propellant tank evaporation rate affected by those factors. Based on the above conclusions, this article analyzes the practicality of the different thermal protection systems and put forward some reasonable suggestions.