Performance Investigation And Parameters Optimization Of The Circular Involute Scroll With Variable Cross-section

Scroll compressor has been widely used in industry,medical treatment and transportation because of its advantages over other compressors in structure,performance and environmental protection.Scroll is the core component of scroll compressor,because the variable cross-section scroll has better comprehensive performance than the constant cross-section scroll,the study of its profile and performance has become a research hotspot.In this paper,the geometric performance,mechanical performance and multi-objective optimization design of the circular involute scroll with variable cross-section are studied.The results can provide theoretical basis for the performance research and optimization design of scroll compressor.The main research contents are as follows:(1)According to the meshing principle of scroll profile,the profile equation and geometric model of the baseline of the circular involute scroll with variable crosssection are established.The mathematical model of the circular involute scroll with variable cross-section is obtained by using baseline and normal equidistant method.According to the principle of tooth head modification,the 2D and 3D models of the modified scroll are established.(2)According to the principle of volume calculation,the formula for calculating the working chamber volume of the circular involute scroll with variable cross-section is established,and the variation law of the working chamber volume with the orbiting angle is analyzed.The geometric and mechanical performance models of the circular involute scroll with variable cross-section and the constant cross-section scroll are established.By comparing the performance of the two kinds of scroll,it is concluded that the circular involute scroll with variable cross-section has better comprehensive performance.(3)According to the established geometric and mechanical performance models of the circular involute variable scroll with cross-section,the influence of the profile parameters on the geometric and mechanical performance of the circular involute variable scroll with cross-section is analyzed by using the control variable method and the sensitivity analysis method respectively,and the influence trend and degree of the profile parameters on the geometric and mechanical performance of the scroll are obtained.It provides a reference for the selection of optimization objectives and optimization variables in the multi-objective optimization design process of the circular involute scroll with variable cross-section.(4)The advantages and disadvantages of NSGA-II,MOPSO and MOEA/D in the multi-objective optimization design of the circular involute scroll with variable crosssection are compared,and the results show that the NSGA-II algorithm is superior in the optimization process and the optimization results.Using NSGA-II algorithm,multiobjective single initial parameters and multi-initial parameters optimization are carried out respectively for the geometric performance and integration performance of the circular involute scroll with variable cross-section,and the Pareto optimal solution set is obtained after optimization.In the multi-objective optimization of geometric performance,the ratio of tooth area to scroll area of optimized scroll decreases by23.81%,the suction volume increases by 5.49%,but the axial gas force increases by30.84%.The results show that the compression ratio of the optimized scroll increases by 16.14% and the axial gas force decreases by 5.62% in the process of multi-objective optimization.It is proved that the multi-objective optimization design of the circular involute scroll with variable cross-section can effectively improve its geometric and mechanical performance.