Software Implementation And Performance Evaluation Of Rotor Profile Design For Lobe Rotor Pumps

With the continuous development of economy and society,the level of science and technology has been improving,and the demand for hydraulic machinery in industry has been increasing,among which,the lobe rotor pump has a very wide application prospect in petrochemical,metallurgy,aerospace and energy industries because of its smooth operation,wear resistance,less clogging,low maintenance cost and low energy consumption.In recent years,scholars and enterprises have started to pay attention to the research of lobe rotor pump and achieved remarkable research results.The lobe rotor has achieved great innovation in structure,and developed towards spiralization and multi-lobe.The current rapid development of computer technology has led to changes in CAD(Computer Aided Design)technology,and more and more people are devoted to the secondary development of CAD software,while there is a great lack of rotor design software for lobe rotor pumps,which leads to frequent problems of low efficiency,slow speed and cumbersome steps when performing rotor design for lobe rotor pumps.Based on this,this study uses a lobe rotor pump as the object of study and selects a circular-involute-circular rotor profile with a high volume utilization factor to complete the development of rotor profile design software.Firstly,from the theoretical design,the rotor design process of the lobe rotor pump is analyzed,including performance design parameters such as flow rate,displacement and volume utilization coefficient,geometric parameters such as outer diameter,center distance and diameterlength ratio,and profile parameters such as base circle radius,spreading angle and knotted circle pressure angle,and all the parameters are constructed and linked to provide a theoretical basis for the parametric design of subsequent software development.Based on the principle and method of Solid Works secondary development,this study applies Visual Studio development tools to interface with Solid Works,completes the development environment,selects suitable interface objects through macro recording and API documentation,and uses C# language to design and develop the lobe rotor pump with good human-computer interaction interface based on COM technology and programming method.Based on COM technology and programming method,we designed and developed a software with good human-machine interface for the design of rotor profile of lobe rotor pump using C# language.The software can realize the three-dimensional model and two-dimensional engineering drawing of the rotor of the lobe rotor pump,which greatly improves the efficiency of the design of the lobe rotor.In order to verify the accuracy of the performance of the rotor profile design software,this study validates the performance design parameters of the software through numerical simulation and experimental methods.Based on the RNG k-εturbulence model and dynamic grid technology,numerical simulations of the lobe rotor pump were performed using Pumplinx software,and a lobe rotor pump performance test bench was built to experimentally verify the performance for specific design conditions.By varying the differential pressure,rotational speed,and diameter-length ratio parameters,the flow data from the design software,numerical simulation,and experiments were compared under different operating conditions to evaluate the error range and accuracy of the flow performance of the rotor profile design software.Through the verification,it was found that the error of the flow rate between the rotor profile design software and the experiment was within 3%,and the error of the flow rate with the numerical simulation was within 6%,and the calculation result of the rotor profile design software was closer to the experiment result,and the error was within the allowed range,which was in line with the engineering design requirements.This study analyzes the effects of differential pressure,rotational speed and diameter-length ratio on the performance of lobe rotor pumps to provide users with a certain basis for rotor design of lobe rotor pumps,taking into account the stability of the flow field while improving the overall performance of lobe rotor pumps.The results show that when the inlet and outlet pressure difference increases,the flow rate of the lobe rotor pump gradually decreases,but the flow pulsation remains basically the same,the outlet flow rate becomes smaller,and the radial force on the rotor gradually increases.As the speed increases,the outlet flow rate and outlet pressure of the lobe rotor pump increase to a certain extent,but the outlet flow rate pulsation and pressure pulsation amplitude gradually become larger,while the radial excitation force on the rotor increases,and the radial force Fx component increases by 44.17% and Fy component increases by 6.47%.With the increase of rotor diameter to length ratio,the rotor structure changes,the rotor length becomes smaller,the outlet flow rate decreases,the pressure pulsation intensity increases,but the flow pulsation amplitude and the radial excitation force of the rotor are reduced.