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对称可倾瓦推力轴承的热弹性流体动力润滑 总被引:1,自引:0,他引:1
本文对对称可倾瓦推力轴承的热弹性流体动力润滑特性进行了理论分析,考察了温升、轴承零件的弹性变形和热变性,轴承前端的冲击压力、流体的惯性力等四类因素对轴承工作性能的影响。数学模型中的全部方程均用无量纲形式给出,并用数值方法求解,从而得到了给定条件下润滑油膜的压力、形状、温度、速度等的分布规律。 相似文献
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水润滑滑动轴承是高压海水泵关键配对副,由于水介质的弱润滑性,轴承副存在严重的摩擦发热,进而引发热卡滞等问题。考虑轴承接触表面沟槽不同构形,建立了轴承的承载与散热模型,研究沟槽数量和形状对润滑支撑和散热的影响。仿真表明:四沟槽轴承的最大温升为39.14℃,八沟槽轴承的最大温升为24.77℃,两者相差36.7%,随着沟槽数量的增加,轴承散热性能得到优化;随着沟槽数量增加,轴承内表面的最大接触应力和变形量也随之增加,相较于四沟槽轴承,八沟槽轴承的最大接触应力增加了5%,最大变形量上升了12%。因此,综合考虑沟槽结构对轴承整体支撑性能和散热作用的影响,设计双向六沟槽螺旋结构,实现海水泵轴承副内循环冷却。 相似文献
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针对动压轴承形状设计的局限性,提出了基于泛函的动压轴承形状设计方法,利用具有表征动压轴承型线函数特征的泛函集成形式表示动压轴承膜厚方程并建立控制方程,以轴承型线的泛函系数为变量,以轴承的最大承载力为目标进行形状优化.通过实例分析,得出用新方法设计出的轴承形状摆脱了原始形状的限制,并且其优化结果优于用传统方法得到的结果.该方法为设计出新的具有最佳性能的轴承形状提供了新的思路. 相似文献
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薄壁零件制造过程中的变形控制研究是现代制造领域的重要课题.针对某新型航空相机上薄壁轴承环零件复合制造工艺的复杂性,对该薄壁轴承环(GCr15轴承钢)进行了淬火工艺的Deform 3D仿真研究.根据淬火工艺参数范围列出多因素多水平的正交实验表,进行不同的试验组合模拟试验,分析影响淬火质量因素的主次关系并优化出最佳水平条件:以5℃/min的加热速度将零件加热到840℃,保温15min后在20℃流动油中淬火冷却.最后对该优化条件下的薄壁轴承环进行了淬火变形仿真分析,获得了淬火变形影响规律以及较好的淬火质量,为轴承环的后续机加试验研究奠定了理论基础. 相似文献
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本文研究瓦面变形对扇形瓦推力轴承的承载状况的影响,对于给定瓦面形状时的计算以及对轴承进行的弹性流体动力分析都表明,轴承在平面瓦和变形状态下都可能存在单值承载区、双值承载区和无承载能力的区域。各承载区域随瓦变形的型式和大小产生连续的迁移和变形,使通常按平面瓦设计的工作点发生变化。在轴承的理论分析中,特别是弹性或热弹性分析中,也会由于轴承工作区的变化使数值计算出现比较复杂的情况。 相似文献
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计及轴受载变形的粗糙表面轴承热弹性流体动力润滑分析 总被引:6,自引:0,他引:6
同时计及表面形貌、热效应和轴承表面(热和弹性)变形等,对轴受到载荷作用产生变形,导致轴颈在轴承中倾斜时滑动轴承的热弹性流体动力润滑性能进行研究,主要分析讨论表面热变形等对粗糙表面倾斜轴颈轴承热弹性流体动力润滑性能的影响.计算中,采用基于平均流量模型的广义Reynolds方程进行轴承的润滑分析,采用变形矩阵方法计算轴承表面(热和弹性)变形,采用能量方程和热传导方程计算润滑油和轴承的温度分布.结果表明,计及表面热变形时,半径间隙对轴承最大油膜压力、最小油膜厚度、油膜压力和油膜厚度的分布有较大影响;轴承载荷越大,表面热变形对轴承性能的影响越显著;表面热变形对轴承性能的影响程度与转速高低有直接关系,转速越高,表面热变形的影响越大;相比于表面弹性变形,表面热变形对轴承性能的影响较大;表面形貌是否影响轴承性能以及影响程度与轴承表面变形情况有较大关系,仅考虑热变形时,表面形貌有一定影响,同时考虑热变形和弹性变形时,表面形貌的影响非常小. 相似文献
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Analysis of heavy duty tilting-pad journal bearing taking into account pad distortion and possible adoption of rubber pad segments 总被引:1,自引:0,他引:1
In this work a comparative study has been made between the thermo-hydrodynamic performance of a three shoe tilting-pad journal bearing with rigid and elastic pads subjected to unbalance load. A case study of a bearing adopting three rubber pad segments has also been studied. The distortion of the elastic pad is introduced into the distribution of the film thickness through an iterative scheme to assess its effect on the load carrying capacity of the bearing. A finite element mesh is used to calculate the distortion of the elastic pad while a finite difference mesh is used to calculate the pressure field in the lubricant film. Results have shown a number of interesting conclusions regarding the adoption of rubber pad segments instead of tilting-pads. There is an increase in minimum oil film thickness when using elastic pad or even rubber pad segments compared with rigid pads. Also the maximum pressure and load carrying capacity are not significantly affected. 相似文献
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研究轴颈挠度和瓦块表面热弹变形对卧式水电机组径向滑动轴承静态润滑性能的影响。推导考虑轴颈挠度和轴瓦热弹变形后的油膜厚度表达式;用中心差分法结合ANSYS软件联立求解雷诺方程、能量方程、固体热传导方程、密度方程、黏度方程和轴瓦热弹变形等,得到径向滑动轴承的热弹流润滑(TEHD)特性,并与不计入轴颈挠度及轴瓦热弹变形的油膜动压润滑特性进行比较。结果表明:在考虑轴颈挠度和轴瓦瓦面热弹变形的影响后,油膜压力、温度、厚度沿着轴承宽度中心线的对称特性消失;油膜压力峰值增大,峰值点位置由轴向中心区偏移至出口区;油膜温度峰值增大,最高温度发生在出口区;润滑区内的最小油膜厚度大幅度减小,油膜最小厚度处于出口侧边界附近;轴承润滑流量减小,损耗略有增大;轴承稳态运行时,轴颈偏位角基本一致。 相似文献
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Lü Changchun 《机械工程学报(英文版)》2002,15(3):279-283,288
The viscoelastic properties of the normal PTFE plastic and strengthened PTFE plastic for bearing pad are measured. The mechanical properties of the composite material for bearing pad, which is made of the aforementioned plastics as matrix reinforced by fine bronze elastic springs, are modeled and relaxation modulus of the material are presented. The difference between these two kinds of PTFE is studied. The results show that the complex modulus of PTFE plastics for bearing pad is higher than that of normal PTFE plastics. 相似文献
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For several reasons, almost all bearings operate in a misaligned condition, the present research work deals with analyzing the performance of a misaligned tilting-pad journal bearing under transient loading condition. The elastic and thermal distortions of the pad are considered and finite element analysis is used to calculate the pad’s elastic deformation. Using finite difference method, the Reynolds equation is simultaneously solved with the energy equation to calculate the pressure distribution and hence the other bearing performance characteristics. A modified fluid film thickness equation is used to take the effect of shaft misalignment and bearing elastic and thermal distortion into consideration.The results have shown that considering the thermo-elasto-hydrodynamic distortion improves the bearing performance in the case of misalignment shaft. And, at low values of shaft misalignment, the decrease in oil film thickness due to shaft misalignment is compensated by the increase in oil film thickness due to elastic and thermal distortions. 相似文献
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建立刚性球头支撑和弹性橡胶垫支撑可倾瓦推力轴承热弹流耦合模型;在弹性橡胶垫支撑可倾瓦推力轴承橡胶垫的弹性变形分析中采用了变形协调矩阵方法,以协调匹配橡胶垫变形和水膜厚度分布,同时在搜索稳态解的过程中引入模拟退火算法;基于变分原理求解Reynolds方程,得到了轴承水膜压力分布,并比较2种推力轴承在转子存在角不对中时的静特性。结果表明:理想工况下,刚、弹支可倾瓦推力轴承稳态特性没有明显区别;当转子存在不对中时,刚性球头支撑可倾瓦轴承在不同瓦块之间受力偏载严重,进而导致瓦面最小水膜厚度过小,瓦块容易出现磨损,而弹性支撑瓦不同瓦块之间水膜力分布更均匀,利于轴承的长期可靠运行。 相似文献
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针对可变流道栅板密封,以外凸变形的流道侧壁为边界条件,建立了栅板密封在弹性元件预紧力作用下适应流道侧壁变形的理论分析模型。基于合理假设,通过分析桥接元件和栅板工作状态,指出栅板密封存在泄漏间隙和悬浮间隙;提出了工作状态下栅板密封间隙大小及分布的计算方法,为研究栅板密封流固热耦合问题提供了几何边界条件;分析了栅板厚度、桥接元件刚度和弹簧参数等对栅板密封随动效果的影响,指出泄漏间隙随栅板厚度减小而单调减小,悬浮间隙随桥接元件弹性模量和截面惯性矩减小而减小,并随弹簧刚度或数量的增加而线性减小。 相似文献
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C.M.McC. Ettles 《Wear》1980,59(1):231-245
For a pad with any given support system, the design can be scaled up directly without size effects provided only elastic distortion is considered. However, thermal distortion tends to increase directly with bearing size. By considering a wide size range of geometrically similar bearings with disc supports it is shown that the maximum obtainable unit loading decreases approximately exponentially with size.Large bearings are particularly prone to failure by a thermal ratchetting process. This effect is far less marked in small bearings where the maximum load is more likely to be limited by film thickness or mechanical strength. Methods of controlling the effects of thermal distortion are discussed. 相似文献
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ANALYSIS ON LAPPING AND POLISHING PRESSURE DISTRIBUTION OF HARD MAGNETIC DISK SUBSTRATE 总被引:1,自引:0,他引:1
0INTRODUCTIONInthemagneticrecordingsystem,thelowertherecordingflyingheightbetweenthemagneticheadanddisk,thehighertheareareco... 相似文献