A magnetically controlled spiral capsule robot is designed. When the robot is running in a pipe filled with mucus, computational fluid dynamics is used to analyze the fluid field (velocity, streamlines, and vorticity) in the pipe, and particle image velocimetry is used to measure the above fluid field surrounding the robot. The measured fluid field is basically similar to the numerical result. The relationship between the operating parameters of the robot and the performance of the robot is further calculated and analyzed. The results show that the resistance to the robot in the forward direction, average turbulent intensity of the fluid surrounding the robot, and maximum fluid pressure to the pipe wall are proportional to the robotic translational speed. The resisting moment of the robot in the forward direction, average turbulent intensity of the fluid surrounding the robot, and maximum fluid pressure to the pipe wall are proportional to the robotic rotational speed.

This study focuses on the phenomenon of oil trapping in the tooth spaces of spur gears.It presents the first obtained results in order to provide an estimation of the powerlosses due to the compression of the oil trapped between the inter teeth meshing spaces ina high-speed transmission for internal and external spur gears. It first allows, to modelthe inter teeth spaces at any time and offers limits for the trapped fluid volume andaxial and radial discharge surfaces. The discretization impact result is discussed.Then,the influence of certain design and operating parameters such as module, pressure angle,addendum modification coefficient and rotational speed on these discharge surfaces andtrapped volume is presented.