Simulation And Experimental Study On Air Flow Field Of High-speed Rotating Disk In The Closed Chamber

Closed chamber rotary disks are widely used as a typical mechanical structure,such as mechanical hard drives,circular saw blades,compressors and so on.In order to improve the stability of the disk,it is of great practical significance and application value to study the coupling characteristics of the fluid and the disk in the closed chamber of high speed rotating disk.In this paper,the characteristics and laws of rigid and flexible rotating disks under gas-solid coupling are studied by means of theory and experiment.The rotating disks with different rotational speed,inclination angle,thickness,axial position and shaft diameter are analyzed.Experiment is designed to verificate the correctness of the theoretical simulation results.First,according to the theory of fluid mechanics,the flow field of rigid rotating disk in closed chamber is analyzed theoretically.Based on the internal cavity structure of the server hard disk,the three-dimensional model of the air chamber is established and the grid is divided.With Fluent software,the boundary conditions are set according to the real flow state of the fluid and the simulation is performed.The results of the velocity field,pressure field and vorticity field of the rigid disk chamber are studied at different rotational speeds.The results show that the velocity and pressure in the chamber ascend with the disk speed increased.At the specified speed,the velocity and pressure increase gradually along the radius of the disk.At high rotating speed,the head has obvious influence on the flow field in the chamber.Secondly,the gas-solid coupling characteristics of flexible rotating disks in closed chamber are further studied.The flexible rotating disk models and chambers with different rotational speed,inclination angle,thickness,axial position and shaft diameter are established.The COMSOL software is used to simulate the gas and disks by two-way gas-solid coupling.Finally,the results are post-processed to obtain the stress-strain cloud and gas velocity of the cloud under the action of gas-solid coupling.The effects of rotating disk displacement and stress on the velocity and pressure distribution in the chamber were investigated.The results show that the coupling between the disk and the fluid causes the inclined disk to have deformation perpendicular to the motor shaft.The disk position ascends and the pressure in the chamber decreases and the change of the speed is not obvious.The disk stress and the pressure decreases and the fluid velocity ascends with the increase of shaft diameter;when the thickness increased,the stress ascends and the displacement decreases.Finally,the experimental schemes are designed and experimental software and hardware are built to carry out experimental study of closed chamber rotating disk.The sealing chamber is constructed by using a plexiglass plate,and three pressure sensors are arranged equidistantly in the radial direction of the upper cover,and the tachometer is arranged on the outer edge.When the disk at different rotating speeds and axial position of the chamber,sensors collect the disk speed and the pressure inside the chamber.The pressure data is processed to obtain the characteristics of the fluid pressure in the chamber with the disk speed and position.The experimental results show that the simulation results of the flexible disk are correct.In this paper,the characteristics of the flow field in the closed cavity of a rigid rotating disk are studied by means of theoretical simulation and experimental verification.The coupling characteristics of the flexible disk and the air in the closed chamber are studied,which has great research value and practical significance.