Research On Pneumatic Conveying Characteristics Of Cutting Particles In Mars Regolith Subsurface Detection

The subsurface detection represented by drilling is the most direct and effective means to construct the Mars geological deep exploration profile and obtain the information of Martian regolith,geology,planetary physics and planetary chemis tr y,which has gradually become a hot spot in international research in recent years.The use of detection equipment to penetrate into the regolith for subsurface detectio n requires long-distance drill cuttings with limited volume,mass,and energy consumption,so that the regolith that occupied the penetration space is discharged to Mars surface.This paper proposes a concept of pneumatic chip evacuation system based on the in-situ pressurized collection and utilization of Mars atmosphere.An air compressor is used to collect and pressurize the atmosphere of Mars so that the high pressure gas source can be used to blow the cuttings out of the borehole.This paper focuses on the scientific problem of using the pressurized Martian atmosphere to carry out the pneumatic conveying of regolith particles,and studies the pneuma tic conveying characteristics of regolith particles in the Martian environment,provid ing the basis for the realization of pneumatic chip removal system engineering..Based on the data of the Mars landing detection mission,the characteristics of the Martian near-surface atmospheric environment(including atmosphe r ic composition,temperature,pressure,etc.)and the characteristics of the Martia n regolith particles were analysised,and the Martian environmental boundar y conditions related to the pneumatic conveying of the cuttings were determined.Based on the application background,a scheme design of the Mars drill cutting pneuma tic conveying system based on IBR robot is proposed.The theoretical model of the gas supply characteristics of the gas source system is established.The gas supply capacity of the gas source system under different input parameters is analyzed,and the gas velocity and mass flow rate of the airflow flowing through the gas pipeline under the given environmental state parameters are determined.The model was verified by CFD simulation analysis method.The energy consumption model of the atmospheric in-situ pressurized collection of the gas source system was established,and the energy consumption of the gas supply capacity were determined.Based on the airflow input conditions provided by the gas supply model,a theoretical model of the gas-solid two-phase uniform flow in the regolith conveying pipeline is established,and the pneumatic conveying characteristics of particles under different input conditions under Earth and Mars environment are analyzed.The evaluation parameters of the particle conveying effect were determined.Further more,based on the evaluation parameters of particle conveying effect,the equiva le nt criterion of pneumatic conveying between the environment of Earth and Mars is proposed.In addition,the energy loss of the particle conveying process is analyzed to guide the selection of process parameters for pneumatic conveying.A pneumatic conveying experimental platform was built and a simula nt of Martian regolith particles for pneumatic conveying experiments was selected.Through the orthogonal test method,the conveying effect of regolith particles by the airflow under different boundary conditions was studied.The main effects of each input parameters on the conveying effect were analyzed.The theoretical model was modified and the basic conclusions of the theoretical model were verified.