Analysis of vortex shape in compressor operation
1 With the vigorous development of China's automobile industry, refrigeration equipment such as refrigerators and air conditioners are becoming more and more popular, and equipments such as medical equipment, pharmaceuticals, brewing, food, electronics, electric power, light industry, machinery, chemical industry, etc., or as processing centers are used for compression. The special requirements of air and other turbocharged, scroll engines, etc., the theory of vortex compression based on conjugate curve meshing and cavity volume change is widely studied by researchers all over the world and applied to scroll compressors. Designed and manufactured. This is of great significance for improving the compression efficiency, reducing energy consumption, reducing noise pollution, suppressing global warming and causing global atmospheric circulation anomalies, avoiding the occurrence of rare and unusual snowstorms, and improving the quality of human life. During the 11th Five-Year Plan period, the increase in the localization of complete sets of equipment in the petrochemical industry, chemical industry, coal and electric oil industry, textile industry, metallurgical industry and other major fields and the intensification of the world energy crisis have provided tremendous development for the compressor industry. The market has also provided an unprecedented opportunity for the compressor industry to speed up the improvement of compressor quality and catch up with the world standard. The design theory and production technology of scroll compressors will have a big breakthrough and leap at home and abroad. Carrying out original research work, it is imperative to have a scroll compressor with independent intellectual property rights in China. 2 vortex line research development status The design theory of scroll type is the fundamental factor determining the performance of scroll compressor. It has always been the hotspot of scholars in various countries. At present, it mainly focuses on the research of single scroll type line design theory. The profiles that have been studied mainly include circular involute, regular polygon involute, line involute, semi-circular involute, algebraic spiral, variable diameter involute, envelope profile, and the like. In terms of the circular involute theory, Japanese scholar Morishita Yusheng first made detailed research, established the vortex compression geometry and mechanics model, and analyzed the compression process; Professor Jens Gravesen of the Technical University of Denmark and other aspects from the perspective of differential geometry theory, The characteristic equations, the circular involute profile theory, point out two ways to obtain efficient lines, and lay the foundation for optimizing the possibility of research; Professor Eckhard A. Groll of Purdue University, etc. The mathematical and thermodynamic performance analysis and leakage model of the whole working process of vortex compression were carried out, and the Newton Raphson algorithm was used to analyze the nonlinear coupling problem between the working chambers. In the aspect of online involute theory, Professor Li Liansheng of Xi'an Jiaotong University conducted an in-depth discussion on the involute of the line segment, derived the volume expression, analyzed the dynamic characteristics, and improved the line involute theory. Japanese scholar Makoto Hayano et al. studied the geometrical characteristics of the semi-circular involute and the analytical relationship between thermal and dynamic forces, and established the profile theory based on semi-circular involute; Huang Yundong of Xi'an Jiaotong University developed a semi-circular involute-based profile. theory. In the theory of algebraic spiral line, the Japanese company Hitachi’s Xiang Zeng and other departments conducted detailed research, and the profile line established by it was called the Hitachi line; later, a new type of scroll line was developed to accelerate the snail. The line is the reference line, and the inner and outer scroll lines are generated by the envelope method. Liu Yangjuan of Huazhong University of Science and Technology has studied and corrected the theoretical fallacy of the Hitachi line, and generated a vortex line by a simpler internal and external normal equidistant line method. However, the current research and design of scroll profiles are based on specific geometric profiles or their combined profiles to study their meshing characteristics and media compressors, and to design the vortex profile parameters due to specific geometric profiles. Once the mathematical model of the curve is determined, its inherent geometric and mathematical properties cannot be changed, and performance is fundamentally constrained. Therefore, the researchers improved and corrected the specific scroll profile, such as increasing the thickness of the root profile, setting the transition arc, using the multi-base circle, changing the position of the center of the base circle, etc., in order to obtain higher performance. Japanese scholar Takahisa Hirano et al. proposed a modified line theory based on the study of vortex compression performance. At the beginning of the base circle involute, based on the consideration of machining and improving the exhaust angle, two sections were used. The arc is corrected, that is, the PMP vortex line. The PMP type line can better improve the compression performance. Then, based on this, researchers from various countries put forward various improvement programs and theoretically demonstrated them, forming a series of improved line theory. The base circle involute correction theory includes the theory of no clearance correction and the theory of clearance correction. The theory of no clearance correction is divided into EA type correction theory and UA type correction theory, while the clearance correction theory is divided into EASA correction theory and EASAL correction theory. . In the correction of the base circle involute profile, the recent research results of Mitsubishi Heavy Industries of Japan are reflected in the fact that the upper edge of the meshing scroll formed by the base circle involute is actually divided into multiple parts and the part The height is low in the center side in the scroll direction and high in the step shape on the outer peripheral end side to improve the compression ratio and performance. Professor Wu Wenfang from Taiwan University studied the meshing principle of planar rotating machinery. Based on the PMP line theory, he carried out in-depth research and introduced the concept of CA, which changed the exhaust angle from negative to positive and derived the contour. Various variations of the profile line, using theoretical deduction and numerical simulation of two mathematical means, the various corrections of the PMP type line are studied, and the optimal correction line is obtained. Dr. Gao Xiufeng from Xi'an Jiaotong University conducted an in-depth study on the isometric arc-shaped vortex correction tooth type, and obtained the general expression of the tooth end generation method, the tooth profile and the tooth end correction parameter, which was derived by the control volume method. The analytical calculation formula of the change of the working chamber volume with the rotation angle of the moving disc is proposed, and the accurate calculation and simplified calculation method of the dynamic radial and tangential gas force area are proposed. A vortex line composed of two or more base circle involutes based on different base circles and starting points, designed by Zhang Yingyi, a researcher at LG Korea, aims to improve volumetric efficiency and reliability. Dr. Wang Guoliang and Professor Li Liansheng of Xi'an Jiaotong University proposed a new type of AAL type line, and studied the combination of double arc and linear unit. Dr. Liu Tao and Professor Liu Zhenquan of Lanzhou University of Technology proposed complex combination lines and studied the dynamic variation of geometric parameters with the rotation of the main shaft. However, the above research improves the compression performance by changing the local shape of a single scroll profile and trimming or combining a single profile. The basis of improvement and combination is based on a single specific profile, and thus it is difficult. Make breakthrough progress. The optimization study of the vortex profile also focuses on the optimization of a single specific profile parameter, and determines the design parameters such as the base circle radius, the starting angle, the vortex number, the vortex wall thickness, the vortex line pitch, and the vortex disk radius. JWBush and other scholars have carried out research work on the size optimization of single scroll profile. Japanese scholar IshiiN et al. optimized the profile structure parameters and obtained a set of specific structural parameters that conformed to the prototype. Professor Liu Zhenquan of Lanzhou University of Technology proposed the research of scroll compressor optimization based on particle swarm optimization algorithm, and established a mathematical model based on particle swarm optimization algorithm for energy efficiency ratio of scroll compressor with static and dynamic scroll, using particle swarm optimization algorithm. In order to optimize the structural parameters of the scroll of the scroll compressor, the optimization design of the dynamic and static scroll based on the genetic algorithm is proposed. Professor Qu Zongchang from Xi'an Jiaotong University established mathematical models for parameter optimization design for different structural parameters. The relationship between the number of criteria and the structural parameters of the profile was introduced. The influence of the number of criteria on the performance was analyzed to obtain the optimal number of criteria. The range gives the preferred strategy for the number of criteria under different conditions. However, the above research is also limited by the mathematical characteristics of the profile line, and can only optimize the profile parameters, but can not optimize the profile, and can not fundamentally remove the constraints, thereby improving the compression performance. At the same time, the research on the performance indexes of scroll compressors is the key factor for the maturity and industrialization of scroll compressors. At present, the research on the performance of scroll compressors mainly focuses on mechanical properties, aerodynamic characteristics, Single performance or single-disciplinary research such as vibration and noise characteristics. However, due to the limitation of single performance or single-disciplinary characteristics, there is no comprehensive consideration of the advantages and disadvantages of the scroll type line from the level of the whole machine. It is also impossible to fundamentally remove the factors that restrict the full performance of the whole machine, thus making it difficult to improve the whole machine. characteristic. 3 Summary and outlook In summary, the research on the design theory of scroll compressors at home and abroad, the starting point or the improvement of the meshing characteristics and the medium compressor mechanism for a given single scroll type mathematical model, Or optimization; or for a single performance or a single discipline of the mechanical properties, aerodynamic characteristics, vibration and noise characteristics of a scroll compressor. However, due to the limitations of the inherent characteristics of the mathematical model of a single vortex line and the limitation of the single performance of a vortex line or the study of a single discipline, the shape function itself of the vortex line character that characterizes the essential characteristics of the vortex line cannot be optimized. At the same time, the full-performance coupling effect of the scroll compressor and the multidisciplinary collaborative design mechanism have not been deeply considered. Therefore, it is difficult to make a fundamental breakthrough in the research and innovation of scroll compressors. Therefore, the design and research of the scroll compressor is based on the improvement of the overall characteristics of the scroll compressor, and the multi-disciplinary collaborative optimization design of the shape function of the scroll line which characterizes the essential characteristics of the scroll line. Research is very critical. The working performance of the scroll compressor is not only related to the design of the scroll line, but also the machining accuracy of the profile, the pulsation characteristics of the vortex flow, the mechanical properties of the mechanism, the dynamic balance characteristics of the scroll, the frictional thermal characteristics, the vibration and noise characteristics, and the compressor. The configuration of power characteristics is closely related. Therefore, the whole-machine coupling effect of multi-discipline synergistic optimization design theory and method for general scroll type lines characterizing the intrinsic characteristics of scroll lines is studied, for the establishment of scroll profile lines. The complete theory and the construction of the best performance of the vortex compression according to the actual situation have great theoretical significance and industrial value. In view of this, this paper proposes a general vortex line design theory and optimization method based on the whole machine characteristics and discipline synergy. It is based on the general scroll type line, using functional analysis theory and multidisciplinary optimization design methods and ideas. The variation law of general scroll shape and its generalized functional convergence characteristics are studied. The shape variation of general scroll shape is determined and the convergence principle of generalized functional of general scroll type line is established. The pulsation characteristics and mechanical properties of vortex flow are studied. The dynamic balance characteristics, frictional thermal characteristics, vibration and noise characteristics, compressor power characteristics, etc. The full-performance coupling effect and multi-disciplinary coordination mechanism and law of general scroll type line machine are obtained. The theory and method of multi-disciplinary collaborative optimization design of general-purpose scroll type line machine are established to optimize the scroll type with the best performance. line. Mixing Hopper,Charging Machine,Feeding Machine Blender&Mixing Machine Mixing Machine Co., Ltd. , http://www.nsdryingmachine.com