管内检测机器人在水平直管内运动的数值研究

采用计算流体力学和动网格技术，数值模拟了单节管内检测机器人在水平直管内从静止到匀速运动这一过程，得到了这一运动过程中机器人的运动规律。计算中将机器人作为运动边界，其受力由当前流场信息来获得，再根据受力来计算机器人的运动速度和前进距离，因边界运动而变化的计算区域根据新的边界条件用弹性变形和网格局部重构技术来更新。不同质量机器人在不同摩擦力下运动规律的计算结果表明，质量只影响机器人达到稳定运动的时间，而摩擦力会影响机器人的稳定运动速度和达到稳定运动的时间。计算结果与实验结果比较吻合，说明动网格技术模拟机器人的运动过程可以为机器人的外形设计、速度控制研究以及操作运行提供参考。

Numerical study on movement of in-pipe inspection robot in horizontal straight pipeline

The movement of single-segment in-pipe inspection robot in a horizontal straight pipe was numerically simulated by the method of the computational fluid dynamics and the dynamic mesh technology, and the law governing the movement of the robot from its initially stationary state to the moving moment at a uniform speed was obtained through the simulation. The robot was regarded as a moving body during the computation, and the force on the robot was calculated from the current flow field, and moving velocity and the distance covered were calculated. The changing computational domain by the moving boundaries was updated by introducing the technology of spring deformation and local remeshing technology. The computation results of the movement of robots of different mass, which are imposed on with different friction, were given. The mass only influences the time that the robot needs to reach a steady state while the friction influences both its final steady velocity and time. The calculated result is in a good agreement with the experimental result. The numeric simulation of the movement of a robot by the technology of dynamic mesh can be regarded as a reference for the shape design, velocity control and operation of a robot.