内啮合转子压缩机齿间接触力研究

内啮合转子压缩机的齿间接触力直接影响到材料的选用、加工的费用，运行的可靠性、啮合的效率等等，目前国内外缺乏相应的计算方法。通过一些合理的假设，采用弹性力学方法，建立了齿间接触力的数学模型，通过选取一定的压缩机结构和运行参数，对齿间接触力和支撑力进行了求解。计算的结果表明，每个外齿在转动一周的情况下将Z2次和内齿之间产生接触力，而且接触力和气体力相比数值很小。研究结果对内啮合压缩机的设计有一定的指导作用。     

结构参数对内啮合转子压缩机受力特性的影响

在分析内啮合转子压缩机独立结构参数对转子影响的基础上,通过定义2个相对结构参数,将影响较大的3个独立结构参数关联在一起,研究了相对结构参数对工作腔压力分布、转子上承受的气体力和气体力力矩以及主轴驱动力矩的影响。研究结果表明,λe对气体力和内外转子上的气体力矩影响较大,随着λe的增大,气体力逐渐减小,内外转子上承受的气体力矩波动加剧,特别是当λe增大到一定值后,外转子上气体力矩会始终为负;λa对主轴驱动力矩影响较大,随着λa的增大,驱动力矩的平均值和变化幅度均增大。在不考虑其他因素的情况下,选择较大的λe和较小的λa对改善压缩机受力情况有利。研究结果可为内啮合转子压缩机的设计及结构参数优化提供一定的参考。     

摆动转子压缩机受力分析与理论计算

在较大压差工况下,摆动转子压缩机比滚动活塞压缩机有更明显的优势。但由于其独特的结构,导致部件受力复杂,使实际设计计算缺乏理论依据。为此,本文对各部件受力进行了理论分析和数值计算。结果表明:气体力是影响大多数力变化的主要因素,部分运动部件之间存在较大的作用力;排气阀开启时刻,各作用力达到最大值;除气体力形成的负载力矩外,摆动转子与偏心轮之间的力矩是压缩机内的第二大负载力矩。     

考虑气体力影响的涡旋压缩机转子系统稳定性研究

针对气体力对涡旋压缩机转子系统造成的动不平衡问题,建立了考虑气体力作用的涡旋压缩机曲轴转子系统力学模型、力与力矩平衡方程,采用平衡铁与曲柄销错开一定角度安装的方法,平衡惯性力和气体力引起的转子系统动不平衡。通过数值计算获得不同转速条件下动平衡所需主副平衡铁质量、平衡铁安装角,并分别与传统设计方法下应用于变转速工况时的结果进行了对比分析,结果表明:该方法能有效的减小主副轴承、机架的受力,提高涡旋压缩机的稳定性,对涡旋压缩机的生产应用有一定的参考指导意义。     

螺杆空压机转子受力有限元计算研究

螺杆压缩机转子受力的准确计算是保障压缩机可靠性的基本条件。本文利用有限元方法对螺杆空压机阴阳转子所受气体力进行了分析计算,提出了实现转子受力计算的有效、快速的方法及实施方案。同时对转子所受轴向力进行了试验测试,验证了该方法的准确性。     

含运动副间隙的涡旋压缩机驱动轴承动力学仿真分析

以某卧式涡旋压缩机转子系统为研究对象,针对动涡盘倾覆力矩作用下运动副间隙对驱动轴承动力学特性影响问题,建立含运动副间隙的转子系统动力学模型,根据计算结果在ADAMS软件中添加气体力进行仿真分析。仿真结果表明:运动副间隙对驱动轴承的加速度和碰撞力影响较大,轴承存在固定的偏磨区域,且间隙越大影响越显著,转子系统的精度和可靠性越差。仿真结果为涡旋压缩机的优化提供了重要的理论参考。     

环板式行星分度凸轮机构针齿受力分析

为了了解环板式行星分度凸轮机构的受力情况,以便对机构的针齿进行强度校核,从而进行强度设计,故对凸轮与针齿之间的受力情况进行了分析.用向量对凸轮与针齿的啮合状态、受力状态及受力针齿进行了数学表示,建立了变形协调条件,根据力矩平衡条件求出了凸轮与针齿之间的作用力的大小和方向.研究结果表明,该机构存在凸轮与某些针齿脱离接触的时刻,接触的针齿未必参与受力,针齿是否参与受力要根据该时刻该接触点的压力角大小而定,针轮所受总啮合力的变化规律与从动件的运动规律一致.     

基于离散像素法的双螺杆压缩机螺杆转子间隙布置方法

为了保证双螺杆压缩机转子在工作运行时的平稳性,提出了一种基于离散像素法的啮合间隙布置方法,根据像素筛选原则及间隙判定原则,结合齿轮啮合及磨损原理, 基于双螺杆压缩机转子的齿廓型线特征以及转子在加工工况下的热膨胀仿真结果,对双螺杆压缩机阴阳转子的齿间间隙布置方法进行了研究,利用所提方法可在一对无啮合间隙的阴阳转子的端面型线上合理布置齿间间隙,调整转子啮合位置,减小双螺杆压缩机运行过程中的振动和磨损,降低运行功耗。     

刮板输送机链轮链条啮合特性分析

链传动系统是刮板输送机的关键部件,链轮链环是链传动系统的关键部件,驱动链轮与链环的啮合力学行为与驱动链轮的磨损相互影响。为了研究链轮与链环啮合过程中链轮与链轮接触力的规律,首先从链环与链轮啮合过程进行理论分析,并对链轮链环啮合过程接触力的变化进行了分析,然后建立基于MSC.Adams的刮板输送机链轮链环虚拟样机模型,分析正常启动至长期输送功率工况下链轮与链环接触的动力学特性,分析得出环链与链轮啮合过程中接触合力、接触切向力和接触法向力的变化规律及接触力的最大值和对应的位置,最后基于LS-DYNA软件对链轮链环啮合过程进行了接触应力进分析,得出链轮链环啮合过程中接触应力最大值和对应的位置,为链轮链环啮合接触研究提供了参考。     

基于Recurdyn履带式海底行走机构不同工况性能分析

针对海底钴结壳和热液硫化物矿区的地形力学特点,在传统路面履带式车辆的基础上,设计了实心轮-橡胶履带啮合式海底行走机构。根据该履带式海底行走机构的结构特点进行动力学建模,在处理啮合力时,应用弹性接触理论,将啮合力等效为弹性接触力;对机构的驱动力进行分析,并对影响因素进行分析。基于Recurdyn搭建海底行走机构简化动力学模型,施加约束、接触力及运动函数控制,针对机构在海底运行时的不同类型的地形环境及工况进行分析。由分析结果可知,实心轮与履带销的啮合力随着其间的正压力变化而变化,正压力达到最大值对应出现最大的啮合力,且正压力和啮合力随着履带的传动出现周期性变化的趋势;同时,由于履带速度的动载荷造成行走机构的速度、加速度、驱动力矩等有较大的脉动,但是从整体上来讲,啮合驱动式行走方案还是相对较平稳的。     

四列氮氢气往复压缩机外力及其平衡的分析与计算

以4M50-27.3/18.5-260型氮氢气往复压缩机为研究对象,分析了作用在其曲柄连杆机构上的各作用力,从振动的角度对其受力进行分析与分类,可知往复惯性力、旋转惯性力及倾覆力矩能传到机器外部而引起压缩机的振动,属于“外力（或外力矩）”,并用Matlab软件,计算分析且绘制了压缩机列的气体力、往复惯性力、往复摩擦力和活塞力图.利用添加基础或弹性支承或者通过各列曲拐错角的合理配置的方法,对引起振动的外力进行平衡,有效减小机器的振动与噪声.     

驱动轴承内嵌式双涡旋齿涡旋压缩机气体力的分析

使用涡旋型线始端展角和终端展角几何参数,对驱动轴承内嵌式双涡旋齿涡旋压缩机的吸气容积、排气容积、压缩比建立了计算公式;对作用于双涡旋齿动涡盘的气体力建立了分析模型;并通过计算与传统的双涡旋齿气体力进行了比较。结果表明,驱动轴承内嵌式双涡旋齿涡旋压缩机相对于传统的双涡旋齿涡旋压缩机,切向、轴向和径向气体力均减小,输气量更大,运行更平稳。     

渐开线行星齿轮啮合力的动态仿真

利用solidworks建立了参数化渐开线齿轮三维实体模型,并导入多体动力学分析软件ADAMS.根据Hertz弹性撞击理论,在齿轮之间施加碰撞力,实现了齿轮啮合.并对行星齿轮啮合过程进行了仿真分析,研究了在不同条件下啮合力的变化情况.     

A Contact Force Model Considering Meshing and Collision States for Dynamic Analysisin Helical Gear System

The current research on gear system dynamics mainly utilizes linear spring damping model to calculate the contact force between gears. However, this linear model cannot correctly describe the energy transfer process of collision that often occurs in gear system. Focus on the contact-impact events, this paper proposes an improved gear contact force model for dynamic analysis in helical gear transmission system. In this model, a new factor associated with hysteresis damping is developed for contact-impact state, whereas the traditional linear damping factor is utilized for normal meshing state. For determining the selection strategy of these two damping factors, the fundamental contact mechanics of contact-impact event a ected by supporting forces are analyzed. During this analysis, an e ect factor is proposed for evaluating the influence of supporting forces on collision. Meanwhile, a new restitution of coe cient is deduced for calculating hysteresis damping factor, which suitable for both separation and non-separation states at the end of collision. In addition, the time-varying meshing sti ness(TVMS) is obtained based on the potential energy approach and the slice theory. Finally, a dynamic analysis of a helical gear system is carried out to better understand the contact force model proposed in this paper. The analysis results show that the contribution of supporting forces to the dynamic response of contact-impact event within gear pair is important. The supporting forces and dissipative energy are the main reasons for gear system to enter a steady contact state from repeated contact-impact state. This research proposes an improved contact force model which distinguishes meshing and collision states in gear system.     

部分负荷工况下双螺杆制冷压缩机转子轴向受力试验研究

为了提高双螺杆压缩机运行的可靠性,对部分负荷工况下转子轴向受力进行了试验研究,测量了部分负荷下压缩机转子齿槽内气体压力的变化趋势以及转子轴向受力的变化特性,并根据转子轴向受力组成,分别得到了气体轴向力和端面轴向力对转子轴向受力的影响.研究结果表明:随着负荷降低,由于转子工作过程压缩段长度的减小,转子轴向受力呈现出不断减...     

An improved friction model and its implications for the slip, the frictional energy, and the cornering force and moment of tires

An improved friction model was proposed with consideration of the effect of the sliding speed, the contact pressure and the temperature, and it was implemented into a user subroutine of a commercial FEM code, ABAQUS/Explicit. Then, a smooth tire was simulated for free rolling, driving, braking and cornering situations using the improved friction model and the Coulomb friction model, and the effect of the friction models on the slip, the frictional energy distribution and the cornering force and moment was analyzed. For the free rolling, the driving and the braking situations, the improved friction model and the Coulomb friction model resulted in similar profiles of the slip and the frictional energy distributions although the magnitudes were different. The slips obtained from the simulations were in a good correlation with experimental data. For the cornering situation, the Coulomb friction model with the coefficient of friction of 1 or 2 resulted in lower or higher cornering forces and moments than experimental data. In addition, in contrast to experimental data it did not result in a maximum cornering force and a decrease of the cornering moment for the increase of the speed. However, the improved friction model resulted in similar cornering forces and moments to experimental data, and it resulted in a maximum cornering force and a decrease of the cornering moment for the increase of the speed, showing a good correlation with experimental data.     

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.     

静止叶片式空气压缩机的研究

提出了一种新型静止叶片式空气压缩机,该压缩机具有一个做摆动运动的转子和一个静止不动的叶片,叶片的外端与气缸的内孔壁面密封紧固连接,叶片的侧端与端盖密封紧固连接,借此减少了气体直接从压缩腔向吸气腔窜逸的通道,有效地消除了压缩机在这些部件间的泄漏损失和摩擦损耗。介绍了压缩机的结构特点及工作原理,建立了压缩机的数学模型。研究表明:转子的扭摆惯性力矩对滑块与叶片运动副的摩擦及磨损有较大影响,应减小转子的转动惯量以降低滑块与叶片间的接触力;转子与端盖的轴向间隙对压缩机内部泄漏损失十分敏感,应采取轴向密封措施以减少转子轴端处的泄漏量。