Research On Volatilization-diffusion Characteristics And Thermal Disturbance Model Of Lunar Soil Water Ice

As the closest extraterrestrial object to human beings,the moon has important scientific value for human beings to explore the universe,and is one of the important goals of human space exploration.The remote sensing results show that there is a lot of indirect evidence to prove the existence of water in the form of water ice on the lunar polar region.Therefore,the task of detecting water ice on the lunar polar surface has gradually become an important subject of lunar exploration projects in various countries in recent years.Existing research results show that the main storage area of lunar water ice is in the permanent shadow area of the lunar polar regions.This area is in an extremely low-temperature vacuum environment all year round.In this environment,water ice material can only exist in the form of gas-solid two-phase and is easily disturbed by the heat generated by the detection equipment during the contact detection process,which will cause sublimation phase change and the loss of sample water content and the distortion of detection data.In response to this detection problem,this paper uses experiments as the main research method to study the volatilization characteristics of lunar soil water ice under vacuum and low temperature conditions.This paper takes ice-soil mixture under vacuum environment as the research object,designs and builds an experimental platform for quantitative volatilization analysis,and conducts a large number of volatilization experiments under vacuum environment.According to the experimental results,the main influencing factors of its volatilization characteristics were explored,and a microscopic model of volatilization diffusion related to environmental parameters and sample parameters was established,and pore gas storage was used as a physical constraint.Based on the experimental results,Using ice vacuum phase change physics to analyze the volatilization-diffusion unit model,deriving the calculation model of volatilization-diffusion in the microscopic state based on the fractal theory of porous media and Darcy's law.Then numerical simulation software was used to write a simulation program for the model.Combine the volatilization unit based on the finite element method,and perform simulation calculations to verify the experimental results,and carried out a simulation analysis for the thermal disturbance during the drilling process,obtained the calculation results of the disturbance state under different working conditions,and designed a realistic environment experiment to verify the analysis result.By studying the physical phenomena of volatilization and diffusion under the vacuum of lunar soil water ice,a set of microscopic models with temperature-pore ratio as the main input parameter and a water-ice disturbance calculation method are obtained.This model can be used to calculate and evaluate disturbance of lunar soil water ice during drilling exploration.This research has enriched and improved the space detection technology for extraterrestrial volatiles,and at the same time has certain engineering guiding significance for my country's future lunar water ice detection mission regulations...