基于最小油膜厚度的齿轮基本参数选择

利用Dowson-Higginson公式推导出齿轮基本参数与最小油膜厚度的关系式，并基于Matlab编程绘出相应的关系曲线图，通过关系曲线图揭示出齿轮基本参数对最小油膜厚度的影响规律。最后，结合传统设计参数选择的理论，提出在满足强度、寿命前提下提高润滑性能基本参数的选择原则，为齿轮设计中基本参数的选择提供了理论指导。     

齿轮啮合沿齿面油膜厚度的分布

总结了齿轮啮合时油膜厚度分析计算的方法,并对一般机械工业中重合度ε＞1,即存在两齿啮合的普遍情况的油膜厚度进行了分析计算,得到了齿轮传动沿啮合线的油膜压力、油膜形状,为齿轮传动的失效分析和摩擦学设计提供分析计算基础.     

齿轮传动抗胶合模糊可靠性分析与计算

阐述了一般工程机械的齿轮传动抗胶合可靠度的计算，分析了可靠度计算中的模糊性，给出了抗胶合模糊可靠度的计算公式，并以实例予以说明。     

齿轮传动模糊可靠性优化设计

依据统计学和模糊数学理论,考虑设计参数的随机性和模糊性,建立圆柱齿轮传动模糊可靠性优化设计的数学模型;并针对实例进行计算,给出最优参数,验证了此模型和优化方法的正确性和可行性.     

具有模糊可靠度约束的双圆弧齿轮传动设计参数的模糊优化设计

在充分考虑了双圆弧齿轮传动各设计参数的模糊性和随机性基础上，结合传统的优化设计方法，探讨了具有模糊可靠度约束的双圆弧齿轮的模糊优化方法。     

机械强度模糊可靠度计算的一种方法

利用最大应力最小极限应力的概念,建立了机械强度的模糊可靠性计算公式,推导出最大应力和最小极限应力具有常用隶属函数时模糊可靠度的计算公式。     

球磨机减速器齿轮传动的模糊优化设计

介绍了球磨机减速器齿轮传动单目标优化问题数学模型的建立，在以体积为最小的基础上，提出以模数、齿数，螺旋角，齿宽为主要优化目标的单目标函数，并采用模糊设计理论和惩罚函数子程序相结合进行优化，通过对实例进行计算，结果表明该方法经济可靠，收敛速度快。     

应力和强度均为模糊变量时的模糊可靠度计算方法

提出了一种应力和强度均为模糊变量时,模糊安全事件隶属函数的确定方法,进而给出了该情况下,模糊可靠度的直接计算方法及随机模拟方法,其原理同样适用于解决应力和强度其它不同组合时,模糊可靠度的直接计算问题。     

基于闪温法的传动齿轮抗胶合可靠度分析与计算

以Block闪温法为基础，论述了齿轮传动抗胶合可靠性分析模型和计算方法，并用实例加以说明，为探索可靠性技术在齿轮抗胶合承载能力计算中的应用进行了有益的尝试。     

齿轮强度的模糊可靠性设计

本文根据模糊可靠性设计理论,对齿轮强度的模糊可靠性设计计算方法进行了初步的探讨,并给出了计算实例。     

An experimental investigation into the oil film thickness of Wildhaber/Novikov gears using a simulation machine: Part I

The basic requirements for simulation of conditions of contact between W/N gear teeth are discussed. A disc machine based on a crowned cylindrical disc rolling inside a hollow cylinder has been designed, manufactured and used for experimental measurements [1]. The details of design and the extent of simulation of W/N gear tooth contact condition achieved on this disc machine are discussed in this paper. The results of measurement of oil film thickness along with instrumentation details will be published in Part II.     

基于熵理论的齿轮强度的模糊可靠性设计

针对模糊可靠性设计中隶属函数特征值确定困难的问题,引入熵理论,可以在不完全依靠经验的前提下,对齿轮可靠性的模糊程度进行数值计算,定量地描述隶属函数特征值与可靠性的关系,给出了应用示例,为机械模糊可靠性设计提供了新方法。     

A study on the circumferential groove effects on the minimum oil film thickness in engine bearings

This paper presents the effects of circumferential groove on the minimum oil film thickness in engine bearings. The fluid film pressures are calculated by using the infinitely short bearing theory for the convenience of analysis. Journal locus analysis is performed by using the mobility method. A comparison of minimum oil film thickness of grooved and ungrooved bearing is presented. It is found that circumferential 360° groove only reduces the absolute magnitude of the oil film thickness, but 180° half groove affects the shape of film thickness curve and position of minimum oil film thickness.     

Effect of proprietary oil additives on elastohydrodynamic film thickness

A study is reported of the effect on a simulated elastohydrodynamic contact of the addition of three proprietary products to the lubricating oil. Chromatic interferometry was used to study changes in lubricant film thickness. Under the conditions employed it was found that Molyslip did not affect film thickness markedly, but there is evidence that solid particles of molybdenum disulphide did enter the contact. STP and Redex both increased the film thickness as a result of increasing the viscosity, but this effect was greatly reduced at high shear rates. No evidence was found for the formation of permanent or semi-permanent surface films, although results have so far only been obtained at room temperature.     

Relationship between calculated film thickness and wear in elastohydrodynamic contacts of gears

Gear oils are important design elements and it is necessary to establish data relating their performance to operating conditions and gear design. Due to a combination of elastic distortion and increased viscosity due to high pressure, a hydrodynamic film is generated in gear tooth contacts. In this paper the authors consider the use of the Dawson and Higginson equation to relate film thickness to the performance of gears with respect to wear rate and present experimental data obtained using the FZG gear test procedure. Initial results of an experimental programme to determine actual pressure viscosity characteristics within highly loaded contacts are also presented, since the authors consider that it is errors in the pressure viscosity relationship that cause the lack of correlation between theoretical film thickness and experimental data on scuffing.     

基于Matlab的动压轴承油膜特性仿真研究

对动压轴承的静特性求解方法进行了理论研究,以Matlab为工具,通过联立Reynolds方程、能量方程、温粘关系及膜厚方程,利用差分法,编制计算程序,对油膜厚度场、温度场、压力场进行了数值求解,分析了油膜厚度、温度及压力分布规律。以某动压轴承为例,计算得出了该轴承下瓦的温度、压力及膜厚的数值,并获得了其三维模型,实现了油膜特性的可视化,使其具有较强的真实视觉感,有助于提高滑动轴承的设计质量,为轴承故障诊断提供了一种可行的途径。     

Quantitative elastohydrodynamic film thickness of mechanically degraded oil

The low-shear viscosities of new oil and used (degraded) oil were measured to moderately high pressure. Shear-thinning flow curves were generated over a range of shear stress important to EHL film forming. Mechanical shear degradation only affected the viscosity at low shear stress while the viscosity at high stress remained unchanged. A recently published film thickness equation for double-Newtonian shear-thinning, employing the measured rheology, predicts the surprising result that thickness of the EHL film was not changed by the degradation although the low-shear viscosities were reduced substantially. Colorimetric measurements of the film thicknesses validate the predictions. Concern over the permanent loss in viscosity due to degradation may be misplaced when addressing EHL films.     

Development of a method to calculate the strength reliability of tooth gears based on the fatigue resistance when the teeth bend

A verified method is discussed regarding how to calculate the strength reliability of tooth gears when they bend and thus resist fatigue. It is based on the computer simulation of random values and the mathematical apparatus of nonparametric statistics. The effective and tolerable bending stresses are described with samples generated by nonparametric sensors. It allows for the correct assessment of the probability of the failure-free performance of tooth gears under any loading conditions.     

Simultaneous monitoring of oil film thickness and temperature in fluid film bearings

This paper reports on the application of an eddy current sensor with an active compensation for changes in sensor temperature to simultaneous monitoring oil film thickness and temperature in a tilting pad thrust bearing. Sensor design, calibration procedure, sensitivity and accuracy are described. Test equipment along with sensor mounting is also presented. Tests were run at different rotational speeds and bearing loads as well as different supplied oil flow rates to evaluate sensor performance in various operating conditions. During the tests film thickness and temperature were simultaneously measured. Temperatures were compared with data from thermocouples installed in the pads and thermistors mounted in the collar. Tests have shown that the sensor can successfully be used to reliably monitor the conditions within the bearing.     

The investigation of oil film thickness in heavily-loaded contact

An experimental study of the shape and thickness of the oil film during rolling in a thrust ball bearing has been carried out by the interference method.The experimental results showed good agreement with theory. Oil film thickness was affected mainly by the rolling velocity, viscosity of oil and maximum Hertzian stress. The groove radius had no effect on the film thickness. With increase of rolling velocity the film thickness increases and then reduces sharply owing to temperature rise and the non-Newtonian properties of the lubricant. A qualitative similarity was derived from the experimentally observed dimensionless shapes of the film and of the dimensionless theoretical shapes of the oil film for the lubricant in the non-Newtonian state. The flat “squashed” contact area diminished and disappeared with rise in velocity, which agreed with theoretical predictions.Good agreement was found between the theoretical and the experimental values of the oil film thickness and the friction coefficients for a ball sliding on a plane. Values of relaxation time for oil agree with values observed by the vibration method.The interference method is proposed to estimate the relation of the relaxation time for lubricants to the pressure and temperature up to maximum Hertzian pressures of 14,000 kg/cm². Experimental studies by the interference method and the solution of the non-isothermal hydrodynamic contact problem for liquids both in the Newtonian and non-Newtonian state provide a method of calculation of the friction coefficient.