二阶连续变截面涡旋压缩机的综合特性分析

发布时间：2018-06-08 09:56

本文选题：组合型线 + 二阶连续　；参考：《兰州理工大学》2016年硕士论文

【摘要】：涡旋压缩机以其高效节能、微振低噪等明显优势而备受关注,广泛应用于空调、真空泵、制冷等行业。涡旋压缩机因其结构设计和运行方式的独特性,使其关键零部件涡旋盘的几何与力学特性直接影响着涡旋压缩机性能的提高,因此涡旋式压缩机综合特性的研究分析具有重要意义。组合型涡旋压缩机在减少涡旋圈数的同时又能实现高压比,缩短了工作介质在腔内的流动时间,减少了泄漏量,因此组合型线涡旋压缩机的研究得到了广泛的关注及在工业上的大量应用。目前研究较多的变截面组合型线多是以一阶连续为光滑边界条件构造而成的,对于以二阶连续为条件构造的组合型线的研究分析少之又少。针对这种现状,本文提出了一种新型二阶连续的组合涡旋型线,并建立几何模型及力学模型,通过对所建模型的联立求解,并与一阶连续组合型线涡旋压缩机的力学特性数据结果进行对比,分析不同型线之间的构造方式对其工程性能的影响。具体内容有以下四方面:(1)以圆渐开线—高次曲线—圆渐开线为母线构造组合涡旋型线,通过对涡旋型线及其工作过程的分析建立工作腔的动态容积模型,在此基础之上,依据整机结构特性进一步完成对力学模型的构建。(2)运用MATLAB分析软件对所建的容积和力学模型进行求解,首先分析压缩腔容积特性和工作介质的压力-时间历程,其次分析工作运行条件中的动力学特性,尤以轴向、切向及径向气体力为主,并将二阶连续与一阶连续的进行综合对比,阐述了两者的优势与差异。结果表明:型线的不同构造方式对机构的动力学特性的影响显著,其中轴向气体力波动相差不大,一般在5N以内,而切向和径向气体力的幅值波动和变化速率有显著影响。当曲轴转至型线连接点处,二阶连续和一阶连续的作用力差值达到最大。(3)研究组合型线在连接点处连续性条件对其综合性能的影响,选取不同的连接点展角1j,2j及高次曲线弧长,通过MATLAB软件对所建立的容积模型和力学模型进行求解分析,将所得的二阶连续组合型线的分析结果和一阶连续的数据进行对比分析。结果表明:连接点展角位置及高次曲线弧长主要影响切向和径向气体力的波动波动和变化速率。(4)基于现有加工设备对所设计的涡旋盘进行实体加工,并采用表面粗糙度仪对涡旋盘精度进行检测,结果表明:曲率连续变化有利于提高涡旋盘的加工精度,对于涡旋盘啮合过程中的接触刚度和疲劳强度有较好的改善。
[Abstract]:Scroll compressor is widely used in air conditioning, vacuum pump, refrigeration and other industries because of its obvious advantages such as high efficiency and energy saving, small vibration and low noise. Because of the unique structure design and operation mode of the scroll compressor, the geometric and mechanical properties of the scroll disk, the key component of the scroll compressor, have a direct impact on the performance improvement of the scroll compressor. Therefore, it is of great significance to study and analyze the comprehensive characteristics of scroll compressor. The combined scroll compressor can reduce the number of vortex circles at the same time realize the high pressure ratio, shorten the flow time of the working medium in the cavity, and reduce the leakage. Therefore, the research of combined vortex compressor has been widely concerned and widely used in industry. At present, most of the combinatorial lines with variable cross-section are constructed under the smooth boundary condition of first order continuity, but the analysis of combinatorial lines with second-order continuous condition is very rare. In view of this situation, a new type of second order continuous combined vortex profile is proposed, and a geometric model and a mechanical model are established. Compared with the results of mechanical characteristics of the first order continuous combined line scroll compressor, the influence of the construction mode between different profiles on its engineering performance is analyzed. The main contents are as follows: (1) taking the circular involute, high order curve and circular involute as the busbar to construct the combined vortex profile, the dynamic volumetric model of the working cavity is established through the analysis of the vortex profile and its working process, on the basis of which the dynamic volume model of the working cavity is established. According to the structural characteristics of the whole machine, the construction of the mechanical model is further completed. The MATLAB analysis software is used to solve the volume and mechanical model. Firstly, the volume characteristics of the compressed cavity and the pressure-time history of the working medium are analyzed. Secondly, the dynamic characteristics of the working conditions are analyzed, especially the axial, tangential and radial gas forces, and the advantages and differences between the second order continuous and the first continuous are comprehensively compared. The results show that the dynamic characteristics of the mechanism are significantly affected by the different structural modes of the profile, in which the axial gas force fluctuates little, generally within 5 N, while the amplitude fluctuation and the rate of change of the tangential and radial gas forces are significantly affected. When the crankshaft turns to the joint point of the shape line, the difference between the second order continuous force and the first order continuous force reaches the maximum.) the influence of the continuity condition of the combined shape line at the joint point on its comprehensive performance is studied. The different joint point extension angle 1J / 2j and the arc length of the high order curve are selected. The volume model and mechanical model are solved and analyzed by MATLAB software, and the results of the second order continuous combined profile are compared with the first-order continuous data. The results show that the angle position of joint point and arc length of high order curve mainly affect the fluctuation and change rate of tangential and radial gas forces. The surface roughness instrument is used to detect the accuracy of the scroll disk. The results show that the continuous change of curvature is helpful to improve the machining accuracy of the scroll disk, and the contact stiffness and fatigue strength of the vortex disk during meshing are improved better.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TH45

【相似文献】