发动机羽流作用下的实时月尘运动仿真

Real time simulation for lunar dust blown by engine exhaust plume

月尘运动是月球探测器软着陆过程中不可或缺的重要环节,针对发动机羽流作用下月尘运动真实感不强和月尘颗粒运动模型过于简单的问题,提出了一种逼真的实时月尘运动仿真方法.通过计算流体动力学(CFD,Computational Fluid Dynamics)和二次谢别德插值(Quadratic Shepard)方法,分析和计算单个月尘颗粒的运动学模型,得到一定初始条件下粒子运动的二维轨迹曲线;通过分析粒子的数量、初始位置、初始速度、生命周期等参数对粒子运动学的影响和变化规律,抽象出月尘系统的粒子集;建立基于月尘粒子集的月尘运动模型.实验结果显示:该运动模型逼真的模拟了发动机羽流作用下月尘腾起、飞溅、弥漫、消散等运动过程,视觉真实感和实时性能良好,对研究真空环境中的月尘运动及月球软着陆等相关领域具有一定的参考意义.目前该方法已应用于北航虚拟现实国家重点实验室月球软着陆仿真系统.

The spray of lunar dust at a lunar landing site is necessary for lunar soft landing simulation. For the model that predicted trajectories of lunar dust blown by the engine exhaust is too simple and the 3D visualization is not strong sense of reality, a physics-based simulation for real-time movement of lunar dust was presented. Using computational fluid dynamics（CFD） and Quadratic Shepard＇ s interpolation, the lunar dust particle trajectory path was simulated by analyzing and computing the ballistics model. A set of particles in the lunar particle system was extracted by analyzing number of particles, initial position, initial velocity, life cycle and other parameters on particle kinematics and variation. Lunar dust particle system based on the particle set was built. The results show lunar dust particles propelled by engine exhaust including jumping, splashing, diffusing and dissipating with visual realism and good real-time. This method has a certain significance for studying trajectories of lunar dust in a vacuum and other related fields. The method has been successfully applied in simulation system of a lunar soft landing.