Study of Hydrodynamic Lubication Mechanism based on the Theory of Turbulence

基于湍流理论的流体动力润滑机理研究

• 批准号: 61460101
• 负责人: NAKABAYASHI Koichi
• 金额: $ 3.97万
• 依托单位: Nagoya Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-61460101/
• 关键词: Fluid Mechanics; Turbulrnt Flow; Lubrication; Couette Flow; Sinusoidally Waved wall; Pressure Gradient; Inertia Effect; 非平衡乱流; 乱流クエット流; 波状壁乱流

First of all, turbulent plane Couette flow has been experimentally investigated to consider the structure of turbulent lubrication in an unloaded journal bearing. Mean velocity and turbulence have been measured in essentially fully developed flow from laminar to turbulent region. Mean velocity profiles are compared with theoretical profiles and the results of direct numerical simulation in the transition region. In the fully developed turbulent region, the velocity follows the logarithmic velocity profile U^+=2.5lny^++ 5.1 obtained by telbany and Reynolds in the wall region but outside the buffer layer layer, and the velocitybany and the velocity-defect law (U_c-U)/u*=R_f(1-y/h) in the core region, where U_c, u* and h are centerline vrlocity, friction velocity and half channel depth, respectively. Skin friction coefficient, turbulence intensity, Reynolds shear-stress and energy-density spectra are also discussed in comparison with the other results obtained previously.Subsequently, the … More structure of turbulent flow in the lubrication for the eccentricity ratio m=0.3 in a loaded journal bearing has been experimentally investigated in the two-dimensional channel between a sinusoidally waved wall and a plane noving belt. The flow is accelerated and decelerated in the main flow direction with the pressure gradient alternating in sign,so that the turbulence is in disequilibrium and greatly influenced by the inertia effect of the flow. The velocity profiles in the wall region are displaced above the logarithmic velocity profile of the turbulent Ciuette flow, depending on y^+ and x/1 (x=coordinate in the direction of main flow ; 1=one wavelength of sinusoidally waved wall). The value of U^+ in the wall region can be given by the function of both Van Driest damping constant A^+ and Karman constant k, which depend on a perssure gradient parameter <nu>dp/dx/(<rho>u*^3) and an inertia effect parameter. Half-power law and velocity defect law were also found in the gradient layer and the core region, respectively. Distribution of Reynolds shera-stress is much influenced by the inertia effect of normal velocity component caused by the secondary flow. Turbulence in tensities,ROO<<U'^2>> and √<V'^2>, were also measured and discussed. Less

首先，湍流平面Couette流已被实验研究，考虑在空载滑动轴承湍流润滑的结构。在从层流到紊流区基本上完全发展的流动中测量了平均速度和紊流度。将平均速度剖面与理论剖面和过渡区直接数值模拟的结果进行了比较。在充分发展的湍流区，在缓冲层外的壁区，速度服从Telbany和Reynolds的对数速度分布U^+=2.5lny^++5.1;在核心区，速度服从对数速度分布U ^+=2.5lny^++5.1，速度亏损定律（U_c-U）/u*=R_f（1-y/h），其中U_c，u* 和h分别为中心线速度、摩擦速度和半槽深。分别文中还讨论了表面摩擦系数、湍流强度、雷诺剪应力谱和能量密度谱，并与已有的结果进行了比较。 ...更多信息 在正弦波形壁面与平面环带之间的二维通道中，对偏心率m=0.3的滑动轴承中的润滑湍流结构进行了实验研究。流动在主流方向上加速和减速，压力梯度的符号交替变化，使湍流处于不平衡状态，并受流动惯性效应的影响很大。壁面区域的速度分布在紊流的休埃特流的对数速度分布之上，这取决于y^+和x/1（x=主流方向的坐标; 1=正弦波形壁面的一个波长）。壁面区域的U^+值可以由货车Dryest阻尼常数A^+和卡门常数k的函数给出，它们取决于压力梯度参数<nu>dp/dx/（<rho>u*^3）和惯性效应参数。在梯度层和核心区分别存在半幂律和速度亏损律。二次流引起的法向速度分量的惯性效应对雷诺切应力的分布有很大的影响。湍流的强度，ROO&lt;&lt;U '^2&gt;&gt;和ROO &lt;V'^2&gt;，也被测量和讨论。少

项目成果

Nakabayashi,Koichi: "Basic Study on Turbulent Lubrication (3rd Report, Turbulence Charac- teristics with Pressure Gradient Alternating in Sign)" Summary of the 65 Annual Conference of Japan Soc. Mech. Engs.(1988)

Nakabayashi,Koichi：“湍流润滑的基础研究（第三次报告，压力梯度符号交替的湍流特性）”日本社会学会第 65 届年会摘要。

中林功一, 鬼頭修己, 岩田裕司, 加藤英司, 上原年: 日本機械学会論文集B編. 54. (1988)

Koichi Nakabayashi、N. Kito、H. Iwata、Eiji Kato、T. Uehara：日本机械工程师学会会议记录，第 B. 54 卷（1988 年）

Nakabayashi,Koichi: "Basic Study on Turbulent Lubrication(1st Report, Turbulent Plane Couette Flow)" Trans. Japan Soc. Mech. Engs.54. (1988)

Nakabayashi Koichi：“湍流润滑的基础研究（第一次报告，湍流平面库埃特流）”，Trans。

Nakabayashi,Koichi: "Basic Study on Turbulent Lubrication (2nd Report, Consideration on Velodity Distribution with Pressure Gradient Alternating in Sign)" Summary of Tokai-branch no.833-1 Conference of Japan Soc. Mech. Engs.883-1. (1988)

Nakabayashi,Koichi：“湍流润滑的基础研究（第二次报告，对压力梯度符号交替的速度分布的考虑）”日本社会学会东海分会第 833-1 号会议摘要。

中林功一, 鬼頭修己, 岩田裕司: 日本機械学会東海支部講演概要集. No. 883-1. 51-52 (1988)

Koichi Nakabayashi、Osumi Kito、Yuji Iwata：日本机械工程师学会东海分会讲座摘要第 883-1 号（1988 年）。