Research On Straight-cylindrical Involute Multi-output Internal Gear Pump

As a typical hydraulic pump,the internal gear pump has the advantages of large displacement,compact structure,large power to volume ratio,small flow pulsation and low noise,but the gear is exerted a great radial force and can not output multi-stage flow at the same time,these problem limit its application and development.In order to solve the above problems,this paper proposes a straight cylindrical involute multi-output internal gear pump.Compared with the traditional internal gear pump,it can reduce the radial force of the driving gear,output two kinds of different sizes of flow and change the way to reduce system overflow losses according to different working conditions.This paper firstly carried out the structure design of the multi-output internal gear pump,introduced its working principle and structure features,analyzed three different working ways,namely,the inside pump working alone,the outside pump working alone,and the both of them working together.Finally,the Solidworks was used to build three-dimensional models of parts and assembly.This paper focused on analyzing the force situation of the gears,the floating crescent board and the floating side plate.It also probed to the influence of the gear arrangement on the radial force of the gears,putted forward the idea of maximizing the reduction of the joint gears while inside and outside pump working together,and used Ansys Workbench software to simulate the strength of the joint gear shaft and the force of the floating crescent board.This paper performed a detailed calculation about the shape parameters of the back pressure chamber of the floating side plate.By using the genetic algorithm of Matlab software,the algorithm function is used to optimize the back pressure chamber parameters.In addition,this paper not only calculated and discussed about the method of reducing the pulsation of the pump output flow,but also deduced the necessary conditions of the output flow pulsation at the inside and outside pump working together way and calculated the leakage of the pump theoretically.At the end of this paper,the two-dimensional flow field of the inside and outside pump is simulated.This chapterdivided the mesh by using Gambit software,and calculated the flow field model numerically by Fluent software,and analyzed the internal flow field pressure and velocity cloud diagram and provided the theoretical basis for the optimization design of the internal flow channel of the pump.According to the theoretical analysis and structural calculation of the whole paper,manufactured the prototype of multi-output internal gear pump and set up the pump performance test rig.The prototype experiment verified the working principle of the pump and provided the experimental basis of the optimization design.