平衡式双螺杆压缩机主机工作过程的数值模拟与仿真分析

发布时间：2018-03-18 14:15

本文选题：双螺杆压缩机　切入点：平衡式　出处：《华东交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：双螺杆压缩机广泛地应用于军工、冶金、石油、化工、船舶、码头、电力、机械、建材、轻纺、造纸、油库、环保、食品等行业。传统双螺杆压缩机通常采用单一工作腔方式，其一端为吸气口，另一端排气口，导致螺杆转子承受单一方向的轴向力作用，而轴向力的大小随着输出压力与排量增加而增大。对于运用石油、石化领域的大排量双螺杆压缩机过大的轴向负载是严重影响其无故障运行周期长短的关键因素。为此课题组为顺应市场需求开展大幅度减少轴向负载的平衡式双螺杆压缩机研制。为了平衡轴向负载平衡式双螺杆压缩机采用双工作腔结构，，其转子受力情况、结构形式与结构参数、内部流场变化情况都有较大的改变。显然照用传统的螺杆压缩机设计理论与方法来进行平衡式双螺杆压缩机设计难以达到最佳效果。鉴此，采用流体力学、建模理论与仿真技术开展排量、螺杆型线、进排气结构条件下转子负载及热变形研究；构建平衡式双螺杆压缩机三维模型；运用ANSYS WORKBENCH等专业软件工具对其主机工作过程进行数值模拟与仿真分析；分析主机流场变化情况等等是加快平衡式双螺杆压缩机研制进程，降低研制成本的必要途径，对实现平衡式双螺杆压缩机的数字化设计起着关键的作用。文中通过对螺杆转子型线几何特性以及压缩机整机性能的研究，确定螺杆转子的外形参数以及压缩机其它主要零部件的结构及外形尺寸；在此基础上，通过PRO/E强大的三维建模能力，建立好平衡式双螺杆压缩机螺杆转子以及其它主要零部件的三维仿真模型，以无缝连接的方式导入ANSYS WORKBENCH中，在其中完成对平衡式双螺杆压缩机的数值模拟与仿真分析；针对如何提高转子轴向力分析精度，对螺杆转子精确加载方法进行了研究，提出了基于啮合接触线加载负荷法；为验证平衡式双螺杆压缩机螺杆转子轴向受力理论上为零，对其进行热应力进行分析；为了了解螺杆压缩机内部的速度场、温度场以及压力场分布情况，分别对传统以及平衡式双螺杆压缩机主机工作过程进行流场分析；为清楚的了解平衡式双螺杆压缩机中隔部以及排气座回流、涡流的分布情况以及影响因素，选取不同工况下，对其进行数值模拟；针对不同排气座结构对其内部回流、涡流的影响，选用了不同的排气座参数，分别对螺杆压缩机整机工作过程进行数值模拟，从中提取相关数据，对排气座的优化、整机的性能以及容积效率的提高有很大的帮助。文中所涉及的实例以及相关数据应用于企业的实际应用，表明了该课题有实际工程应用价值与意义。
[Abstract]:Twin screw compressors are widely used in military industry, metallurgy, petroleum, chemical industry, ship, wharf, electric power, machinery, building materials, textile, papermaking, oil depot, environmental protection, food and other industries. One end of the suction port and the other end of the exhaust port cause the screw rotor to bear a single direction of axial force, and the magnitude of the axial force increases with the increase of output pressure and displacement. The excessive axial load of large displacement twin-screw compressor in petrochemical field is the key factor that seriously affects its fault-free operation period. In order to comply with the market demand, the research group carried out a balanced double-load balancing type to greatly reduce the axial load in order to meet the needs of the market. Development of screw compressor. In order to balance the axial load balance type twin screw compressor with double working cavity structure, its rotor force condition, structure form and structure parameter, The variation of internal flow field has changed greatly. It is obviously difficult to achieve the best result by using the traditional screw compressor design theory and method to design the balanced twin screw compressor. In view of this, hydrodynamics, modeling theory and simulation technology are used to study the rotor load and thermal deformation under the conditions of displacement, screw profile, intake and exhaust structure, and the three-dimensional model of balanced twin screw compressor is constructed. It is necessary to use ANSYS WORKBENCH and other professional software tools to simulate and simulate the working process of the main engine, to analyze the variation of the main engine flow field and to speed up the development process of the balanced twin-screw compressor and to reduce the development cost. It plays a key role in realizing the digital design of balanced twin screw compressor. In this paper, the profile parameters of the screw rotor and the structure and size of other main parts of the compressor are determined by studying the geometric characteristics of the profile of the screw rotor and the performance of the compressor. Through the powerful 3D modeling ability of PRO/E, the 3D simulation model of the screw rotor and other main parts of the balanced twin screw compressor is established, and the 3D simulation model is imported into ANSYS WORKBENCH in the way of seamless connection. In order to improve the precision of rotor axial force analysis, the accurate loading method of screw rotor is studied, and the load method based on meshing contact line is put forward. In order to verify that the axial force of the screw rotor of the balanced twin screw compressor is zero theoretically, the thermal stress is analyzed, and the distribution of velocity field, temperature field and pressure field inside the screw compressor is understood. The flow field of the main engine of the traditional and balanced twin screw compressor is analyzed respectively, and in order to understand clearly the distribution of swirl and the influence factors in the baffle and exhaust seat of the balanced twin screw compressor, the different working conditions are selected. According to the influence of different exhaust seat structure on the internal reflux and eddy current, different exhaust seat parameters are selected to simulate the whole working process of screw compressor, and the relevant data are extracted from it. The optimization of exhaust seat, the performance of the whole machine and the improvement of volumetric efficiency are of great help. The examples and the application of the related data in the enterprise show that the project has practical application value and significance.
【学位授予单位】：华东交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TH45

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