不同重力下月壤水平推剪阻力离散元数值分析

月面环境下重力场仅为地面环境下的1/6,研究重力场对于开挖阻力的影响,对优化设计月面环境下开挖设备具有重要意义。采用离散单元法模拟不同深度不同重力场下的月壤水平推剪试验(简化的土–开挖机械间相互作用模型),分析了重力场对开挖试验中推剪阻力、能量消耗和破坏面的影响,最后建立推剪阻力与重力场的关系。结果表明:相同推剪深度下,随重力场增大推剪阻力和能量消耗均增加,推剪前方受扰动土体范围减小;随推剪深度增加,推剪阻力增加。

DEM analyses of horizontal pushing resistance under different gravity fields

On the lunar surface, the gravity is only 1/6g while it is 1g on the earth surface. Investigating the effects of gravity has great significance to the optimization of excavator designed for lunar excavation. DEM is employed to simulate excavation tests with different excavation depths and gravity fields. The effects of gravity on excavation force, energy consumption and sliding surface are studied. Then the relation among excavation force, depth and gravity is fitted. The results show that the excavation force and energy consumption increase with the gravity while the range of affected area decreases. The excavation force increases with depth.