GEAR算法在随机轨道模型计算中的应用

本文对随机轨道模型中颗粒相常微分方程组的刚性问题进行了分析，结果表明：当采用常规算法如四阶Runge－kutta法求解方程组时，方程组的刚性是导致某些情况下计算发散或计算时间过长的原因。为此，本文将适用于求解刚性方程组的Gear算法应用于随机轨道模型的计算中，取得了良好的效果．     

Measurement of steering gear impedance

Proper simulation of noise in hydraulic circuits requires reliable experimental data to be used in the simulations. In automotive power steering applications, obtaining reliable impedance data for both the pump and steering gear is critical for the success of any fluid-borne noise simulation program. Collecting data for power steering pumps has been the subject of various studies. Steering gears, on the other hand, have received little attention. The purpose of this paper is to present a comprehensive assessment of the need of such data and describe a test setup for obtaining the data according to recent ISO standards. This paper describes the results obtained and presents several studies. In particular, the effects of pressure, steering position, slave pump and steering fluid on rack impedance will be studied. Furthermore, repeatability and production variability of measured data will be addressed.     

引进螺杆压缩机高速齿轮的失效分析与国产化研制对策

本文针对进口螺杆压缩机中的高速驱动齿轮，对其进行了玻坏失效分析和几何参数测定。根据工作特点、运行情况和破坏现象，在选材、设计、制造、热处理和工艺参数选择等方面进行了改进性设计，达到了原设备的使用要求。本文所提供的设计方法对进口零、部件国产化的研制具有一定的参考、借鉴意义。     

生产现场环境中的噪声影响及其改善措施——以某齿轮生产车间为例

采用理论分析和实地调研的方法研究和讨论了噪声对生产现场环境的影响,阐述了噪声对工人健康、生产效率影响的研究现状.在对某齿轮生产车间进行问卷调查和实地测量的基础上,分析了该生产车间的噪声情况,并结合车间实际情况,从声源传播途径控制和接受点采取防护两方面提出了控制噪声的具体实施措施.     

Bifurcation of multi-freedom gear system with spalling defect

This study focuses on the bifurcation characteristics of the four degree-of-freedom gear system with local spalling defect to explore the spalling nonlinear dynamic mechanism. The dynamic model of the gear system with spalling defect, time-variant mesh stiffness, and nonlinear clearance is established to investigate the effect of spalling defect on mesh stiffness and dynamic bifurcation. The primary resonance and internal resonance responses of the spalling model are analyzed by the averaging method, and the bifurcation characteristics with the evolvement of spall and internal excitation are studied by employing the singularity theory for the two-state variable system, which reveal the different bifurcation characteristics caused by the spalling defect. The results obtained herein can provide a theoretical basis to spalling fault diagnosis of gearbox.     

基于承载接触特性的直齿面齿轮滑动摩擦啮合效率研究

为了解决直齿面齿轮滑动摩擦啮合效率的问题,基于弹性流体动力润滑理论,提出了一种计算直齿面齿轮啮合效率的方法.首先,运用轮齿接触分析(TCA)和轮齿承载接触分析技术(LTCA)对直齿面齿轮承载啮合过程进行数值仿真;其次,运用非牛顿准稳态热弹流理论建立滑动摩擦系数的计算模型,从而建立直齿面齿轮啮合效率的计算模型,最后分析了输入扭矩、转速等对啮合效率的影响.结果表明:滑动摩擦系数是影响齿轮啮合效率的重要因素;齿面不同位置滑动摩擦系数也不相同;滑动摩擦系数受输入转速、输入扭矩的影响.该方法为直齿面齿轮的进一步优化计算提供一定的理论依据.     

Modelling dynamic behaviour and noise generation in gear pumps: Procedure and validation

The paper presents a methodology for noise and vibration analysis of gear pumps and its application to an external gear pump for automotive applications. The methodology addresses the use of a combined numerical model and experimental analyses. The combined model includes a lumped-parameter model, a finite-element model and a boundary-element model. The lumped-parameter (LP) model regards the interior parts of the pump (bearing blocks and gears loaded by the pressure distribution and the driving torque), the finite element (FE) model regards the external parts of the pump (casing and end plates), while the boundary element (BE) model enables the estimation of the emitted noise in operational conditions. Based on experimental evidences, attention has been devoted to the modelling of the pump lubricant oil: the fluid–structure interaction between the oil and pump casing was taken into account. In the case of gear pumps all these important effects have to be considered in the same model in order to take their interactions into account. The model has been assessed using experiments: the experimental accelerations and acoustic pressure measured in operational conditions have been compared with the simulated data coming from the combined LP/FE/BE model. The combined model can be considered a very useful tool for design optimisation.     

软质齿轮影像法测量及系统误差和随机误差分析

通过实验了解影像法测量时的误差特性,分别对塑料、木质等软质齿轮公法线及模数在数显投影仪进行测量,并对实验数据进行分析处理,得到测量的系统误差主要来自测量时零线的对齐误差,通过对比检定法计算得出。随机误差主要来自于测量人员对齿廓的瞄准误差,通过A类不确定度进行计算得出。另外测量仪器的不确定度,按B类不确定度计算,由于其远小于A类不确定度,故忽略不计。对比塑料齿轮和木质齿轮测量的结果,得出软质齿轮测量的随机误差与材料、加工特性及表面质量相关的特点。木质齿轮的加工变形小于塑料齿轮,而且加工后齿廓表面质量较好,使得木质齿轮测量的随机误差小于塑料齿轮的随机误差。     

外啮合齿轮泵随机内泄漏模型的研究

为了获得更加精确的外啮合齿轮泵内泄漏数学模型,将不确定性理论引入齿轮泵传统内泄漏模型中进行研究。将齿轮泵的轴向间隙、径向间隙、液压油温度、工作压力和输入转速作为随机变量,运用随机因子法和代数综合法建立齿轮泵随机内泄漏模型,进而获得在不确定性下的齿轮泵容积效率。将随机内泄漏模型研究结果和传统模型的计算结果分别与实验结果进行比较,证明随机内泄漏模型的正确性和优越性。     

谐波齿轮传动减速器的固体润滑失效机理

在同型号的谐波轮传动减速器和相同的试验条件下，考察了不同固体润滑薄膜体系的润滑性能和磨损特性；结合试验后柔轮和刚轮的工作表面形貌和磨粒的分析，初步探讨了固体薄膜润滑下谐波减速器的磨损机理及其润滑失效机理，结果表明，谐波减速器齿轮磨擦副的润滑膜配伍是影响谐波减速器润滑状态和运行寿命的重要因素。在分析研究的基础上，提出了改进谐波减速器齿轮副固体润滑的设想，并且研制出在给定条件下适用的固体润滑薄膜体系。