涡旋压缩机动力特性及仿真模拟研究

发布时间：2018-03-21 01:43

本文选题：涡旋压缩机　切入点：虚拟建模　出处：《兰州理工大学》2014年博士论文　论文类型：学位论文

【摘要】：涡旋压缩机作为一种新型、节能、高效、低噪、省材的容积式流体机械,与其它类型压缩机相比较具有不可替代的优越性,已广泛应用于空调制冷、动力工程等领域。目前逐渐向大气量、大功率的方向发展,应用领域也随之扩大。随着石油化工的发展,压力能的应用日趋广泛,使得涡旋压缩机在国民经济的各个部门成为必不可少的关键设备之一。随着计算机技术的发展和加工制造技术的提高,涡旋压缩机的应用领域得到更为广阔的发展。由于涡旋压缩机特殊的工作原理及结构特点,其潜在的优势并没有完全被挖掘出来。因此,研制与开发高性能的涡旋压缩机具有重大的现实意义。本文依托国家自然科学基金项目“无油润滑涡旋式压缩机的摩擦学与动力学耦合问题研究”和“变容量涡旋压缩机润滑摩擦特性与转子动力学行为研究”,以涡旋压缩机为研究对象,基于圆渐开线理论,建立了涡旋压缩机压缩腔几何模型,泄漏模型、传热模型、动力学模型；借助三维实体建模软件,得到了涡旋压缩机虚拟样机模型；通过转子系统模态、曲轴转子壳体耦合动力学、转子系平衡特性及考虑运动副间隙的机构动力学特性分析,为涡旋压缩机的可靠性设计及高性能研制提供了理论基础。首先完成涡旋压缩机的虚拟建模和运动仿真,包括建立其部件的三维实体模型、对其零部件进行虚拟装配、样机和部件的运动仿真。建立其零部件三维实体模型,根据涡旋压缩机物理样机的结构特点,描述主要零部件之间相互的位置关系和运动关系,从而确定各零部件在虚拟环境中的相对空间位置,进行虚拟样机的装配工作。校核涡旋压缩机设计是否合理、可靠、主要零部件的动作是否协调和运动过程是否存在干涉。在涡旋压缩机虚拟建模的基础上,研究涡旋压缩机转子系统动力特性,根据模态分析理论和转子单元运动方程,分析了主轴系各节点的位移和倾角；基于转子动力学理论,得出了主轴轴承的动力特性系数,建立了主轴轴承为刚性支承系统和弹簧—阻尼系统两种分析模型。应用有限元软件对涡旋压缩机两种分析模型的主轴转子系统进行预应力条件下的模态分析,分别获得了两种支承系统条件下的振型,并分析了弹簧—阻尼系统中轴承刚度对其转子动力特性的影响。利用有限元方法和多体动力学理论,对涡旋压缩机转子和壳体进行有限元模态分析,获得了涡旋压缩机转子和壳体的固有频率和振型等模态特性参数。在涡旋压缩机主轴系拓扑模型的基础上,分别建立了主轴系的多刚体模型和多柔体模型。通过对曲轴系多体动力学仿真分析,得到了气体力载荷和在柔性体条件下壳体承受主副轴承载荷等,分析了壳体在载荷作用下的动力学响应问题。根据曲柄销所受的切向力大小约为径向力四倍,通过采取平衡曲柄销所受切向力大小平均值及极小值的方法,分别分析了曲柄销切向力不平衡残余量以及曲柄销切向力最小值部分对主轴轴承的影响；对涡旋压缩机轴系和壳体进行受力分析,建立轴系和壳体的力和力矩平衡方程,将壳体的受力和主轴轴承载荷作为设计变量,来分析壳体在受力最佳的情况下,平衡重的安装角度对主轴轴承载荷的影响。在涡旋压缩机工作过程中,如果计入尺寸误差、运动副间隙和磨损间隙的存在,那么,涡旋压缩机不能完全满足平行四连杆的条件。因此,以涡旋压缩机虚拟样机为对象,建立考虑运动副间隙的转子系统多体动力学模型,并将含间隙运动副的间隙矢量模型、间隙接触碰撞力模型和摩擦力模型嵌入ADAMS软件进行多体动力学仿真。仿真结果可以准确地预测运动副间隙对涡旋压缩机动态特性的影响,为涡旋压缩机设计提供了参考和依据。通过样机动平衡试验和性能试验,验证了涡旋压缩机的优良性能及可靠性,动平衡试验必要性,为高性能涡旋压缩机的研制与开发奠定了坚实的基础。
[Abstract]:Scroll compressor as a new, efficient, energy saving, low noise, displacement fluid machinery, materials, and other types of compressors compared with irreplaceable advantages, has been widely used in refrigeration and air conditioning, power engineering and other fields. The current gradually to large volume, high power direction, with applications expand. Along with the development of the petrochemical industry, the use of the pressure energy is becoming more and more widely, the scroll compressor has become one of the indispensable equipment in all sectors of the national economy. With the development of computer technology and manufacturing technology, application of scroll compressor has more broad development. Because of the working principle and structural characteristics of scroll compressor special the potential advantage is not completely excavated. It is of great practical significance for scroll compressor and development of high performance. This paper relies on the country The project of National Natural Science Fund "oil-free scroll compressor tribological and dynamic coupling problem research" and "variable capacity lubrication and friction characteristics of scroll compressor and rotor dynamics research, to scroll compressor as the research object, based on the theory of involute, built of scroll compressor chamber geometry model, leakage model, heat transfer model. Dynamic model; using 3D modeling software, the virtual prototype model of scroll compressor; rotor system by modal, crankshaft rotor casing coupling dynamics, consideration and Analysis on the dynamic characteristics of mechanism with clearance balance characteristics of the rotor system, and provides the theoretical basis for the reliability design and high performance of scroll compressor is developed.
Virtual modeling and motion simulation of scroll compressor first, including establishing 3D model of the components of the virtual assembly of its components, and the components of the motion simulation prototype. The 3D model according to the structural features of the physical prototype of the scroll compressor, the relationship of position and motion to describe the relationship between the main components, so as to determine the the relative spatial positions of the components in the virtual environment, virtual prototype assembly work. Check the scroll compressor design is reasonable and reliable, the main components of the action is not the coordination of movement process of the existence of interference.
Based on the virtual model of scroll compressor, scroll compressor dynamic characteristics of rotor system, according to the modal analysis theory and the equation of motion of the rotor unit, the displacement and angle of each node of the main shaft system analysis; based on the theory of rotor dynamics, the dynamic characteristics of spindle bearings, a spindle bearing rigid support and spring damping system two kinds of system analysis model. Under the condition of prestressed modal analysis using the finite element software of scroll compressor two analysis model of spindle rotor system, we obtained two kinds of bearing system under the condition of vibration mode, and analyzes the spring damping system of bearing stiffness influence on the rotor dynamic characteristics.
By using the finite element method and multi-body dynamics theory and finite element modal analysis of scroll compressor rotor and shell, the scroll compressor rotor and housing to obtain the natural frequency and vibration mode modal parameters. Based on the topological model of scroll compressor spindle system, multi rigid body model were established and flexible multi spindle system model. Through the analysis of multi body dynamics simulation of crankshaft system, the gas loading and the flexible body under the condition of the main and auxiliary load bearing shell bearing, analyzes the dynamic response under the load case.
According to the crank pin by tangential force radial force is about four times, by taking the balance of crank pin by cutting method to force the average value and the minimum value, respectively analysis of the crank pin tangential force imbalance residual and crank pin tangential force minimum part of spindle bearing influence; the force analysis of the scroll compressor shaft and housing, and to set up a force and moment equilibrium equations, the shell stress and bearing load as the design variables, to analyze the case in stress optimum conditions, effects of installation angle of the balance weight on the main bearing load.
In the working process of the scroll compressor, if included in the size of the error, existence, clearance and wear gap that cannot fully meet the scroll compressor parallel four link conditions. Therefore, the virtual prototype of scroll compressor rotor system is developed as the object, the clearance of multi-body dynamic model considering the gap, and vector model of the gap the motion model and friction model, embedded ADAMS software of multi-body dynamics simulation gap contact force. The simulation results can accurately predict the effect of clearance on the dynamic characteristics of scroll compressor, to provide reference and basis for the design of scroll compressor.
The performance and reliability of scroll compressor are verified through the maneuverability balance test and performance test. The necessity of dynamic balancing test is established, which lays a solid foundation for the development and development of high-performance scroll compressor.

【学位授予单位】：兰州理工大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TH45

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