滚动转子式压缩机的间隙泄漏模型

根据滚动转子式压缩机内制冷剂间隙泄漏的特点，利用润滑油流动模型来模拟计算制冷剂的泄漏量。计算表明，通过径向间隙的泄漏量最大，其次是通向吸气腔的轴向端面间隙的泄漏量。因此合理地设计泄漏间隙值，可以有效地降低滚动转子式压缩机的泄漏损失。     

采用油膜密封的转子压缩机内间隙泄漏研究

在转子压缩机内转子和气缸之间采用间隙配合，其泄漏通道通过油膜来密封的。考虑到转子径向间隙的动态变化，利用润滑油流动模型来计算它的制冷剂泄漏量，通过保持其它配合间隙不变，只改变转子径向间隙的性能试验来检验油膜的密封效果。结果表明，合理地设计转子径向配合的间隙值，可以有效地降低转子压缩机的泄漏损失。     

转子径向间隙对滚动转子式变频压缩机性能的影响

研究了转子径向间隙对滚动转子式变频压缩机泄漏量及性能的影响，优化出转子径向间隙的最佳取值范围，并通过实验得到了验证。     

双滑片椭圆转子压缩机径向间隙泄漏研究

建立了双滑片椭圆转子压缩机的径向间隙泄漏模型,对不同径向间隙的泄漏量进行了计算和分析,并和相同规格的滚动转子压缩机进行比较。结果表明:椭圆转子压缩机的径向间隙泄漏量在相同条件下大于滚动转子压缩机,两者的差值随着间隙的增大而增大,在间隙为80μm时,椭圆转子压缩机的径向间隙泄漏量最多可比滚动转子压缩机大2.352 g/s;压比对泄漏量的影响较大,在压比一定时,转速和转子椭圆面短轴和长轴之比对泄漏的影响并不明显。严格控制的径向间隙是提高椭圆转子压缩机容积效率的主要因素。     

双叶片转子式压缩机径向泄漏改善及优化设计

通过对双叶片转子式压缩机泵体受力特性分析,结合制冷剂、润滑油溶解特性,建立了双叶片压缩机径向泄漏对容积效率的影响计算模型。通过优化计算发现,双叶片转子式压缩机如果保持原有的圆形气缸设计,由于径向泄漏大增,容积效率较低。只有将气缸内径设计为椭圆形结构,才能有效降低径向泄漏,获得较高的容积效率。     

滚动活塞压缩机径向间隙泄漏特性试验研究

利用自主设计的径向间隙等效装置模拟滚动活塞压缩机的径向泄漏通道,在此基础上研究了压缩机主轴转速、活塞径向间隙值、润滑油黏度、径向间隙油膜密封长度等因素对径向间隙工质泄漏特性的影响。利用气体收集装置对等效装置径向间隙泄漏的气体进行收集,同时用高速摄影记录下收集装置里气泡的动态变化过程,并通过图像处理技术获取气泡的面积,进而转换得到气体的泄漏量。试验表明:径向间隙处的气体泄漏量与转速、油膜密封角、润滑油黏度等因素存在着负相关的变化规律,其中气体泄漏量对转速和油膜密封角的变化表现较为敏感,而对润滑油黏度的变化则反应最小;另外,气体泄漏量与径向间隙值呈现明显正相关的关系。     

压缩机径向泄漏通道润滑油量的实验研究

在压缩机运行过程中,通过径向泄漏通道从压缩腔泄漏到吸气腔的气体泄漏量与堆积在该处的润滑油量有极大的关系,为了准确描述径向间隙处的润滑油量,以滚动活塞压缩机本体为基础设计一套试验装置,采用高速摄影技术对径向间隙处的润滑油进行观察和图像采集,将采集的图像导入MatLab进行图像处理,得到滚动活塞压缩机在运行过程中的径向间隙处的润滑油量。以润滑油密封角为衡量润滑油量大小的指标,分析润滑油密封角与偏心轴转速、供油量、润滑油黏度的关系。结果表明:以汽缸中心点和活塞与汽缸的理论接触点的连线作为分界线,润滑油并不以该分界线作为对称中心均匀地分布在吸气腔和压缩腔两侧,而是整体偏向压缩腔侧,并且该分布规律与润滑油黏度、偏心轴转速和供油量都无关;润滑油密封角随着转速的提高而增大,随着供油量的增大而增大,随润滑油黏度的增加而减小。     

变频滚动转子式压缩机热力性能分析

考虑工质及润滑油的泄漏、吸气加热损失、残余气体膨胀等,采用有限元方法对排气阀建立模型,完善了滚动转子式压缩机的数学模型。利用模型计算和分析了压缩机在变频运行时的响应,并对其变频运行作出性能预测,指出样机合适的变频范围。     

轴承偏置角对滚动转子式变频压缩机性能的影响

研究了轴承偏置角对滚动转子式变频压缩机泄漏量及性能的影咱，并优化出轴承偏置角的最佳值。     

滚动转子式压缩机使用替代制冷剂存在的问题

介绍了制冷剂R22的替代制冷剂的热力学性能，并提出了针对滚动转子式压缩机来选择替代制冷剂的要求、评价标准以及替代过程中需要考虑的问题。     

Estimation of leakage through radial clearance during compression process of a rolling piston rotary compressor

The leakage characteristics during the compression process in a rolling piston rotary compressor were investigated in this research. The thermodynamic conditions and geometric features during the compression process were determined from the results of a numerical compressor simulation. Refrigerant R410a and lubricant oil PVE-68 were used as working fluids. Leakage models with and without consideration of the lubricant oil effect were used to examine leakage characteristics through the radial clearance. A model for pure refrigerant that included the operating conditions and geometric characteristics of a compressor was developed using the verified results of a CFD (Computational fluid dynamics) simulation. The area ratios for both the refrigerant and lubricant oil at the radial clearance was obtained by numerical analysis during the compression process of the rolling piston rotary compressor. The results showed that the cross sectional area at the radial clearance would be charged with the pure refrigerant up to a maximum of 81.2 % during the compression process.

     

叶片铰接滚动转子压缩机的运动分析

介绍了新型叶片铰接滚动转子压缩机的结构特点,与传统滚动转子压缩机相比,具有摩擦功耗少,径向泄漏少等优点,具有相当的优势和发展前景.但是,在叶片铰接滚动转子压缩机的试制初期,发现转子及滚动环有易烧与卡死的现象,为此对叶片铰接滚动转子压缩机进行了运动分析.通过运动分析发现这种叶片铰接滚动转子压缩机存在急回运动的特性,是转子和滚动环烧缸与卡死的主要原因.因此,在结论中提出了相应的注意事项和应对策略.     

Comparison of the Dynamic Behavior and Lubrication Characteristics of a Reciprocating Compressor Crankshaft in Both Finite and Short Bearing Models©

The compression force of refrigerant gas, the viscous and inertial force of the piston, and the centrifugal force of balancer weight induce rotating whirl of the crankshaft in a small reciprocating compressor. It is necessary to develop an analytical model for the accurate prediction of dynamic behavior of the compressor mechanism having coupled characteristics between the piston and crankshaft. The reciprocating compression mechanism is dynamically modeled by considering the viscous frictional force of a piston and the variation in the contact length of the piston-cylinder system, and then numerical analysis is performed for the coupled dynamic behavior of the piston and crankshaft. For the accurate predictions of the dynamic behavior and characteristics of lubrication of the crankshaft-journal bearing system, a finite bearing model is adopted. In addition, the dynamic trajectory and characteristics of lubrication of the crankshaft such as power consumption and oil leakage are compared between the finite bearing model and the short bearing approximation. The influences of the variation in the radial clearance of the journal bearings, lubricant viscosity, and mass and mass moment of inertia of the piston and connecting rod on the dynamic behavior and characteristics of lubrication such as power consumption and oil leakage are investigated.     

Lubrication characteristics of a rotary compressor used for refrigeration and air-conditioning systems (the influence of alternative refrigerants)

The rolling piston type rotary compressor has been widely used for refrigeration and air-conditioning systems due to its compactness and high-speed characteristics. However, it is necessary to develop alternative refrigerants that can guarantee environmental protection. In addition, advanced refrigerant compressors must be further developed to overcome the compatibility problems inherent in refrigeration and air-conditioning systems. The refrigerant compressor is the most important mechanical component, which determines the performances of refrigeration and air-conditioning systems. Therefore, we theoretically investigated the lubrication characteristics of the rotary compressor currently used in both refrigeration and air-conditioning systems with an alternative refrigerant. In the theoretical investigation, the Runge-Kutta method is used to analyze the behavior of a rolling piston in the rotary compressor. Subsequently, the Newton-Raphson method is used, which provided good performance in the analysis of the elastohydrodynamic lubrication of the line contacts between a rolling piston and a vane in the rotary compressor. The results demonstrate that the alternative refrigerants influence the friction force and the energy loss between the vane and the rolling piston.     

叶片铰接滚动转子压缩机的润滑系统分析

新型叶片铰接滚动转子压缩机与传统滚动转子压缩机相比,具有结构更紧凑、摩擦功耗少、径向泄漏少等优点.由于压缩机在运转工作过程中各运动部件间的摩擦不可避免,如果润滑系统设置不合理,将会造成很大的摩擦损失和密封失效,甚至会使零部件因磨损而报废.通过实验研究确定了新型叶片铰接滚动转子压缩机的润滑系统.试验结果表明,新型叶片铰接滚动转子压缩机的润滑系统是合理有效的.     

Lubrication characteristics between the vane and the rolling piston in a rotary compressor used for refrigeration and air-conditioning systems

The rolling piston type-rotary compressor has been widely used for refrigeration and air-conditioning systems due to its compactness and high-speed operation. The present analysis is part of a research program directed toward maximizing the advantages of refrigerant compressors. The study of lubrication characteristics in critical sliding components is essential for the design of refrigerant compressors. Therefore, theoretical investigation of the lubrication characteristics of a rotary compressor used for refrigeration and air-conditioning systems was studied. The Newton-Raphson method was used for the partial elastohydrodynamic lubrication analysis between the vane and the rolling piston of a rotary compressor. The results showed that the rotational speed of a shaft and the discharge pressure significantly influence the friction force and the energy loss between the vane and the rolling piston.     

The Influence of the vane on the lubrication characteristics between the vane and the rolling piston of a rotary compressor

The rolling piston type rotary compressor has been widely used for refrigeration and air-conditioning systems due to its compactness and high-speed operation. The present analysis is part of a research program directed toward maximizing the advantages of refrigerant compressors. The study of lubrication characteristics in the critical sliding component is essential for the design of refrigerant compressors. Therefore, theoretical investigation of the lubrication characteristics of a rotary compressor being used for refrigeration and air-conditioning systems was investigated. The Newton-Raphson method was used for a partial elastohydrodynamic lubrication analysis between the vane and the rolling piston of a rotary compressor. The results demonstrated that the vane thickness and the center line position of the vane significantly influenced the friction force and the energy loss between the vane and the rolling piston.