液液混合两相流中内螺旋管道机器人运行性能分析

Operational Performance of Inner Spiral In-pipe Robots in Liquid-liquid Two-phase Mixed Flow

作为一类重要的无创肠道机器人,目前对螺旋管道机器人的研究都是针对单相液体流,但由于各类流质食物的存在,肠道环境为液液多相流状态。采用计算流体力学(CFD)方法数值,计算内螺旋管道机器人在液液混合两相流中的轴向推进力、流体动压承载量、机器人周向阻力矩和管道内壁所受最大压力等运行性能参数。结果表明:往液体环境管道中加入另一均匀分散的高黏度液体时,随着加入液体体积分数的增大,机器人轴向推进力、流体动压承载量、机器人周向阻力矩和管道内壁所受最大压力均随之增大;当加入的高黏度液体分散不均匀时,随着加入液体体积分数的增大,机器人轴向推进力呈波浪状增大,周向阻力矩也随之增大,但基本都小于高黏度液体均匀分散时的情况。

As a class of important non-invasive intestinal robots,the current research on spiral in-pipe robots at home and abroad is aimed at single-phase liquid flow environment. However,there exist some liquid foods in the actual intestine,the intestinal fluid should be liquid-liquid multiphase mixed fluid. The operational performance parameters of inner spiral in-pipes robots on liquid-liquid multiphase mixed fluid,suah as axial thrust force,fluid dynamic load,circumferential resisting moment and maximum pressure of pipe wall,were numerically calculated by using computational fluid dynamics（ CFD） method. The results show that when another evenly dispersed liquid of high viscosity is dispersed into the liquid pipe,the robotic axial thrust force,fluid dynamic load,circumferential resisting moment and the maximum pressure of pipe wall are increased with the increase of the concentration of the added liquid. When the added liquid of high viscosity is dispersed unevenly,with the increase of the concentration of the added liquid,the robotic axial thrust force is increased in the wave shape,and the circumferential resisting moment is also increased,but they are basically less than those in the case of the evenly dispersion of high viscosity liquid.