译文：本论文描述了发展的数值模拟绕流一个笼罩的螺旋锥齿轮的建模策略。策略，然后施加到一系列关键的护罩参数的参数变化。罩盖和齿轮的问题是通用的，虽然根据所采用的罗尔斯·罗伊斯航空发动机内部的齿轮箱。护罩齿轮的需要来自这样的事实，螺旋伞齿轮，旋转时，像一个风扇的行为。工作是由齿轮移动周围的流体，通常是空气与油颗粒悬浮在里面，这创建了一个寄生损失，简称为风阻功率损耗。在本论文的工作是研究如何风阻功率损耗可以影响由齿轮和罩的几何特征，一个更大的项目的一部分。大直径（200毫米）齿锥齿轮运行在高转速（> 10,000 RPM）的的风阻功率损耗形成的总功率损耗的主要部分，这是很重要的。
已经制定了这项工作的研究4种不同的流体流量设置：Taylor-Couette流，锥形Taylor-Couette流，无罩的螺旋锥齿轮，一个笼罩的螺旋锥齿轮的建模策略。 Taylor-Couette流的工作提供了基本的环境中试验各种数值技术和增益熟悉的CFD的商业计划，将用于整个论文（流利），随着啮合程序GAMBIT。它给了称为锥形Taylor-Couette流的流量，然后将其用于模拟流Taylor-Couette流的变形例中，在气缸与圆锥体所取代，理解。 4流行的湍流模型进行了比较，让一个决定，’^好’的湍流模型使用在一个笼罩齿轮的建模，并开始发展的战略。此策略，然后施加到更复杂的几何形状的一个开式齿轮，模拟实验数据已经上创建了一个内部的钻机。要确认笼罩螺旋锥齿轮建模的策略的适用性，它适用于两个罩，实验数据是可用的。结果表明，数值模拟，可以捕捉到相对性能护罩的。然后继续考虑一系列的参数变化，即3个关键的寿衣参数是不同的3举止，生产27变化的工作。这些参数可以影响风阻功耗：评估每个参数的影响的风阻功率损耗已被赋予多少。在’好’和’坏’的情况下的流场的描述，并通过近似使用可压缩流的伯努利方程的形式，已经提出了一个’坏’的寿衣是’坏’的原因。
原文：This thesis describes the development of a numerical modelling strategy for simulating the flow around a shrouded spiral bevel gear. The strategy is then applied to a series of parametric variations of key shroud parameters. The shroud and gear in question are generic, although based upon those employed in the internal gear box of a Rolls-Royce aeroengine. The need to shroud the gear comes from the fact that a spiral bevel gear, when rotated, acts like a fan. Work is done by the gear to move the surrounding fluid, usually air with oil particles suspended in it, which creates a parasitic loss, referred to as the windage power loss. The work within this thesis is part of a larger project which has investigated how windage power loss can be affected by geometric features of gears and shrouds. This is important as for large diameter (>200mm) bevel gears running at high speeds (>10,000 RPM) the windage power loss forms a substantial part of the total power loss.
The modelling strategy has been developed in this work by studying 4 different fluid flow settings: Taylor-Couette flow, Conical Taylor-Couette flow, an unshrouded spiral bevel gear, and a shrouded spiral bevel gear. Work on Taylor-Couette flow provided a basic setting in which to trial various numerical techniques and gain familiarity with the commercial CFD program which would be used throughout this thesis (FLUENT), along with the meshing program GAMBIT. It gave an understanding of the flow, which was then used to simulate the flow in a modification of Taylor-Couette flow where the cylinders are replaced with cones, called Conical Taylor-Couette flow. Comparisons were made between 4 popular turbulence models, allowing a decision to be made on the `best’ turbulence model to use in the modelling of a shrouded gear, and to start to develop the strategy. This strategy was then applied to the more complex geometry of an unshrouded gear, simulating experimental data which had been created on an in-house rig. To confirm the applicability of the strategy to modelling shrouded spiral bevel gears, it was applied to two shrouds for which experimental data was available. It showed that numerical modelling can capture the relative performance of the shrouds well. The work then continued by considering a series of parametric variations, whereby 3 key shroud parameters are each varied in 3 manners, producing 27 variations. Each of these parameters can affect the windage power loss: an assessment of how much each parameter affects windage power loss has been given. A description of the flow field in `good’ and `bad’ cases has been given, and through approximating the flow by using the compressible form of Bernoulli’s equation, reasons for a `bad’ shroud being `bad’ have been presented.
正文结束!
天勋机械主营：
小模数齿轮，
螺旋伞齿轮，
伞齿轮，
弧齿锥齿轮，
螺旋锥齿轮，
园林工具齿轮，
缝纫机齿轮，
割草机齿轮！
