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基于进化算法的液体动力润滑轴承优化设计 总被引:1,自引:0,他引:1
采用Matlab语言,分别运用改进型粒子群算法和基本粒子群算法,在最大限度满足液体动力润滑径向滑动轴承的承载量系数值,以达到滑动轴承承载能力的条件下,对内燃机径向滑动轴承进行了优化设计,计算机仿真结果表明:采用改进型粒子群算法优化的轴承孔直径、轴径直径、轴承宽度、承载量系数等优化参数效果最好,符合实际工艺要求,且滑动轴承承载能力最强。改进型粒子群算法优化结果明显优于基本粒子群算法的优化结果,从而表明了改进型粒子群算法应用于内燃机问题的优化求解切实可行。 相似文献
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一、引言高压齿轮泵设计中,由于齿轮承受较大的液压径向力,其滑动轴承往往是决定齿轮泵寿命的重要环节。按照传统的滑动轴承设计方法,轴被认为是绝对刚性的,即轴和轴承始终平行。可是由于径向力的作用,轴总要产生一定的挠曲变形。这个变形改变了油膜的形状,因而改变了油膜中的压力分布,使油膜的承载能力发生变化。为了提高轴承的承载能力,往往加宽轴承的宽度以降低轴承比压。但由于宽度增加,轴加长,使其变形更多。故有时这样做并不一定带来好的结果。现代有限元理论的发展为计算带有挠曲变形轴的滑动轴承的计算提 相似文献
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Boncheol Ku Youngdo Park Chiun Sung Youngchul Han Junghoon Park Yujin Hwang Jungeun Lee Jaekeun Lee Hyeongseok Kim Sungyoung Ahn Soo Hyung Kim 《Journal of Mechanical Science and Technology》2010,24(8):1631-1635
This study examined the tribological behavior of journal bearings made from polytetrafluoroethylene (PTFE) composites and aluminum (Al) alloys. The PTFE composite journal bearings consisted of a steel backing with a thickness of 1.6 mm, a middle layer of sintered porous bronze with a thickness of 0.24~0.27 mm, and a surface layer of PTFE filled with fluorinated ethylene propylene (FEP) powder and carbon fibers with a thickness 0.06~0.14 mm. The other was an aluminum alloy journal bearing consisted of a steel backing with a thickness of 1.5 mm and a surface layer of an Al-6Sn-6Si alloy with a thickness 0.35~0.75 mm. A series of lubrication tests were performed using a journal bearing tester under various normal loads. The tribological properties for each journal bearing were evaluated by measuring the lubricant oil temperature and friction coefficient as a function of the applied normal load. In addition, the chemical compositions and microstructures of the journal bearing materials used in this study was analyzed by inductively coupled plasma (ICP), optical microscopy (OM), and scanning electron microscopy (SEM), respectively. The experimental results showed that the Al alloy journal bearings reduce the friction coefficient by 28 % compared to the PTFE composites bearings. In addition, the Al alloy journal bearing worked properly at the maximum load of ~ 8,000 N without adhesion. However, the PTFE composite journal bearings exhibited strong adhesion at the loads ranging from 6300 to 8000 N. This suggests that the Al alloy is a more promising material in journal bearings than PTFE composites. 相似文献
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This paper presents the development of a numerical model for high speed and water lubricated journal bearings with different boundary slip arrangements. The effect of boundary slip and its possible mechanism are analyzed and discussed. The results suggest that a suitable combination of slip/no-slip surfaces on the sleeve of a journal bearing enables improvement of the tribological performance through (i) suppressing the occurrence of cavitation, (ii) enhancing the load bearing capacity, and (iii) reducing the interfacial friction between bearing sleeve and shaft. Such improvement becomes more significant for the bearings with smaller eccentricity ratio, smaller width and larger diameter. 相似文献
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Experimental data were obtained in liquid hydrogen (?423 F) on two series of 40-mm-bore ball bearings utilizing various retainer materials. Effects of diametral clearance and retainer material on limiting DN value (product of bearing bore in mm and shaft speed in rpm) were investigated at thrust loads to 500 lb and at speeds to 41,200 rpm. An analysis was made to determine the effect of ball size and race curvatures on the heat generated in bearings of both series as a result of ball spin. The results, supported experimentally, indicate that higher limiting DN values at a specific thrust load could be obtained with an extremely light series (1908) bearing with open-race curvatures than with a light series (108) bearing. Successful operation to a DN value of 1.6 million was obtained with 1908 bearings (at 110 lb thrust load) using two different retainer materials. The glass-fiber-filled PTFE (polytetrafluoroethylene) retainer exhibited much less wear than the MoS2-filled phenolic retainer at these test conditions. 相似文献
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起飞转速是空气轴承的重要性能指标。以螺旋槽空气轴承为研究对象,运用摄动法求解等温可压缩条件下螺旋槽气体润滑轴承压力分布的微分方程,得到空气轴承压力分布及承载力等特性;以最大承载力为目标,计算螺旋槽空气轴承的结构参数,并对设计的空气轴承进行试验,探究其不同载荷下的起飞速度。试验结果表明:空载状态下,转速约为1 200 r/min时空气轴承的转子与轴承套脱离接触,达到起飞速度;螺旋槽空气轴承的起飞速度与起飞转矩均随着的载荷的增加而逐渐升高,随着转速的升高,轴承的承载能力也越来越大。研究表明所设计的螺旋槽空气轴承具有良好的性能,为后续螺旋槽轴承设计优化及实际应用提供了理论与实践基础。 相似文献
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为研究润滑介质种类对于气浮轴承性能的影响,通过FLUENT对采用空气、二氧化碳、氢气与氦气作为润滑介质的气浮轴承进行数值计算,分别对静压轴承承载力随供气压力的变化趋势以及动压轴承承载力随转速的变化趋势进行分析;并对不同环境压力和温度下的二氧化碳润滑动压气浮轴承承载力变化趋势进行研究。数值计算结果表明:润滑介质种类对于静压、动压气浮轴承的承载特性均具有明显影响;不同润滑介质润滑下静压气浮轴承的承载力由大到小排序大致为空气、氦气、氢气、二氧化碳;不同润滑介质动压气浮轴承承载力变化趋势基本与润滑介质黏度变化趋势保持一致;二氧化碳润滑动压气浮径向轴承的承载力受环境温度与压力的影响主要体现在其工质黏度(随温度与压力)变化,二氧化碳润滑动压止推轴承的承载力随环境压力的增大近似呈线性增大。 相似文献
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Florian Grün István Gódor Wolfgang SailerHans-Peter Gänser 《Tribology International》2012,46(1):119-127
We simulated the tribological functionality of two heterogeneous tribomaterials used in conformal contacts by means of a FEM-based approach: journal bearing material AlSn20 and polymeric sealing material PTFE with bronze filler particles. For AlSn20, the emergency running capability, which is based on the activation (melting) of the soft phase tin, was simulated taking into account thermo-elasto-plastic behaviour of the material. For the PTFE bronze compound, we analysed the load bearing capacity of the particle-structured surface with varying volumetric fraction of particles, temperature, load and creep behaviour of the PTFE Matrix. The results show benefit of heterogeneous designs over homogeneous materials. 相似文献
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Shigeru Inami Satoshi Takayanagi Tomoo Kubo Hidetaka Nanao Ichiro Minami Shigeyuki Mori 《Lubrication Science》2008,20(4):299-310
Poly(tetrafluoroethylene) (PTFE)‐blended poly(ether‐etherketone) (PEEK)‐based materials for bearings was evaluated by ring‐on‐disc test equipment. The role of PTFE on load carrying capacities was studied from the viewpoint of tribochemistry. The load carrying capacities of PEEK‐based materials were improved by the addition of PTFE. The dispersion degree of PTFE in PEEK strongly affected the tribological properties. Time‐of‐flight secondary ion mass spectroscopy and X‐ray photoelectron spectroscopy were employed to study the surface chemistry of the rubbed surface. The results indicate that the formation of boundary film composed of PTFE is beneficial to improve load carrying capacities. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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均压槽与静压气体轴颈轴承承载特性的关系研究 总被引:2,自引:0,他引:2
主要研究通过开设不同结构形式的均压槽来提高静压气体轴颈轴承的承载能力和刚度,利用加权余量法和有限元离散化方法求解雷诺方程进行数值计算和仿真,针对单排孔和双排孔轴颈轴承,分析不同长度的周向均压槽,以及不同数量、不同位置和不同长度的轴向均压槽对轴承承载能力和刚度的影响规律。结果发现:开设周向均压槽和轴向均压槽都可以提高轴承的承载能力,相比开设周向均压槽,开设轴向均压槽对提高轴承的承载能力更为有效,而且只开设一条或两条轴向均压槽就能显著提高轴承的承载能力,通常将轴向均压槽置于气膜间隙较小的位置时能使轴承的承载能力和刚度最大。数值仿真结果通过试验进行验证,研究结果可用以指导高承载和高刚性静压气体轴颈轴承的设计。 相似文献
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Load capacity tests were conducted to determine how radial clearance variations affect the load capacity coefficient of foil air bearings. Two Generation III foil air bearings with the same design but possessing different initial radial clearances were tested at room temperature against an as-ground PS304 coated journal operating at 30000 rpm. Increases in radial clearance were accomplished by reducing the journal's outside diameter via an in-place grinding system. From each load capacity test the bearing load capacity coefficient was calculated from the rule-of-thumb (ROT) model developed for foil air bearings. The test results indicate that, in terms of the load capacity coefficient, radial clearance has a direct impact on the performance of the foil air bearing. Each test bearing exhibited an optimum radial clearance that resulted in a maximum load capacity coefficient. Relative to this optimum value are two separate operating regimes that are governed by different modes of failure. Bearings operating with radial clearances less than the optimum exhibit load capacity coefficients that are a strong function of radial clearance and are prone to a thermal runaway failure mechanism and bearing seizure. Conversely, a bearing operating with a radial clearance twice the optimum suffered only a 20% decline in its maximum load capacity coefficient and did not experience any thermal management problems. However, it is unknown to what degree these changes in radial clearance had on other performance parameters, such as the stiffness and damping properties of the bearings. 相似文献
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以超临界CO 2涡轮机主轴支承静压轴承为研究对象,基于Fluent软件建立静压轴承气膜的三维分析模型,分析了轴承结构、偏心率、气膜间隙对气膜压力、承载力和刚度的影响。结果表明:双排进气结构静压轴承的气膜压力、承载力和刚度均高于单排进气结构;偏心率对承载力有显著的影响,承载力和偏心率呈非线性正相关;在偏心率一定的条件下,平均气膜间隙较小的静压轴承承载力和刚度更高;刚度和偏心率呈现高度的非线性关系,刚度随偏心率的增大先增大后减小,偏心率为0.32时出现极值,且极值前刚度的增长梯度明显高于极值后刚度的减小梯度。 相似文献