Scroll Compressor Based On Combined Profile Change Study On Performance Of Working Chamber

As a new type of high-efficiency volumetric fluid machinery,scroll compressors have the characteristics of regular layout,high efficiency and stability,energy saving and low vibration,etc.,and have been widely used in many industries such as pharmaceutical manufacturing and preservation,food,industrial and agricultural drying and chemical industry.As one of the core components of a scroll compressor,the design of its profile will have an impact on the performance of the scroll compressor,such as leakage,force,power consumption,noise and vibration.Research shows that the combined profile can achieve a larger compression ratio with fewer scroll turns,and has high flexibility in the design process,so it has gradually become a research hotspot in the scroll compressor profile design.In the design of the combined molding line,the position of the molding line connection point is often selected based on the design experience,and the influence of the change of the connection point position on the flow field characteristics in the compression cavity has not been deeply explored.In order to solve this problem,this paper takes the base circle involute+high-order curve+arc combination profile as the research object,takes the position of the connection point between the base circle involute and the high-order curve as a variable,and uses theoretical calculations and numerical simulations.The combined method is used to analyze the influence of the change of the position of the connection point of the two sections on the cavity volume,the pressure and temperature in the cavity and the fluid flow in the cavity.The specific research contents are divided into the following aspects:Firstly,based on the meshing principle of the plane curve,the control equation of the general profile and the isotype theory of the constraint condition of the connection point,the generatrix equation of the base circle involute+high-order curve+circular arc combined profile is deduced;The contour equations of the inner and outer walls of the vortex tooth are generated by the equidistant line method,and the double arc correction is performed on the vortex tooth head,and the calculation formulas of the dynamic volume of the compression cavity and the pressure and temperature in the cavity are given.Secondly,the design parameters of the combined profile of the base circle involute+higher-order curve+arc are determined,and the corresponding mathematical model is established with the expansion angleφ₁ of the connection point between the base circle involute and the higher-order curve as a variable;using MATLAB The software calculates and obtains the curve of the volume,pressure and temperature of the compression cavity of different models under a working cycle,and analyzes them.The results show that when the expansion angleφ₁ of the connection point decreases,the volume,pressure and temperature of the compression chamber increase,and the compression ratio of the scroll compressor formed by this profile increases.The theoretical basis is provided for the optimal design of the combined profile of the scroll compressor.Finally,when the main shaft rotation angle is 0°,89°and 180°,the compression cavity model of the connection point at different expansion anglesφ₁ is established,and the numerical simulation calculation is carried out by the FLUENT software,and the internal pressure field,temperature field and velocity field are obtained.change rules.The results show that with the decrease ofφ₁,the maximum pressure of the pressure field increases,and its variation range becomes larger;the variation law of the temperature field i s similar to that of the pressure field;the smaller the variation range of the gas velocity in the velocity field,the more stable the flow.This is basically consistent with the theoretical calculation results.