共查询到19条相似文献,搜索用时 140 毫秒
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对某发动机涡轮盘的榫齿裂纹断口、材质和受力进行综合分析,结果表明,榫齿裂纹为起始应力较大的疲劳裂纹,盘片材料热膨胀不协调以及存在叶片共振是导致涡轮盘榫齿裂纹的主要原因。另外,GH2036材料在高温燃气环境易发生沿晶腐蚀,是导致涡轮盘提前失效的诱发因素。 相似文献
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枞树形多齿结构榫头的榫槽裂纹是国内外多种型号喷气发动机的危险故障之一.经综合分折,本文指出裂纹故障的主要原因是多齿结构和第一榫齿冷态单齿接触承载。榫头结构因素和热应力是引起第一榫槽裂纹故障的重要原因,而振动对榫槽裂纹扩展也有一定影响。建议对设计、制造和使用各个环节采取一些相应的措施. 相似文献
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几何尺寸误差对盘片接触系统强度影响研究 总被引:1,自引:0,他引:1
应用 ANSYS程序中的弹塑性接触有限元工具 ,系统地分析了榫齿超差对盘片接触系统应力分布的的影响 ,得出了一些对发动机设计和制造有意义的结论。 相似文献
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提出采用超声爬波原位检测飞机发动机叶片榫槽裂纹的方案.设计了爬波探头的数学模型,根据该模型制作了双晶爬波探头.试验结果表明,爬波探头对飞机发动机叶片榫槽裂纹具有较高的检测灵敏度. 相似文献
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镍基单晶涡轮叶片榫头疲劳裂纹扩展寿命研究 总被引:1,自引:0,他引:1
《机械强度》2015,(4):725-729
设计航空发动机涡轮叶片榫头/榫槽接触模拟试验件,基于涡轮叶片的实际工况,进行了榫头/榫槽接触疲劳试验。基于Paris公式提出了榫头接触疲劳裂纹扩展寿命模型,并采用晶体滑移有限元程序对涡轮榫头/榫槽接触进行了有限元模拟。有限元分析得到的疲劳裂纹扩展寿命与试验结果相符,表明提出的疲劳裂纹扩展寿命模型可用于指导分析榫头寿命。 相似文献
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为解决某型航空发动机密封跑道篦齿裂纹问题,对篦齿裂纹分布、微观形貌及断口形态进行观察和分析,对密封跑道的成分、组织及硬度进行检测,对密封跑道的强度及结构设计进行计算分析,确定篦齿裂纹产生的原因:密封跑道上裂纹为疲劳裂纹,裂纹的产生主要与基体材料的硬度低及齿形结构设计强度低有关,同时提出了改进措施。 相似文献
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本文对某发动机一级涡轮盘榫槽槽底的裂纹损伤从实验研究和理论分析二个视角探究裂纹损伤产生的机理及影响裂纹扩展的因素,为采取行之有效的预防措施提供理论依据。 相似文献
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J.A. Becerra Villanueva F. Jiménez Espadafor F. Cruz-Peragón M. Torres García 《Mechanical Systems and Signal Processing》2011,25(8):3168-3185
Diesel engines used in power plants and marine propulsion are especially sensitive to outage events. Any advance in the early detection of failure will increase the reliability of the electricity supply and improve its productivity by reducing costly power outages. Fault detection and diagnosis is important technology in condition-based maintenance for diesel engines. This article presents a classifier based on neural networks for identifying failure risk level in crankshafts, the engine component of greatest cost concern. The authors have developed a finite element model for crack growth that fits well with fracture appearance and produces the evolution of crankshaft stiffness with crack depth. A lumped system model of the engine uses this evolution as input, giving the instantaneous speed at the engine flywheel as a function of crack depth. All the results shown in the paper come from outputs of the simulation models which have been built from real engine data. Measurements of the instantaneous flywheel speed were not available due to the crankshaft failure. All data are extracted from this speed and are then classified using a Radial Basis Function neural network. 相似文献
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粉末冶金涡轮盘裂纹扩展失效概率分析 总被引:6,自引:0,他引:6
建立了考虑应力及断裂参数随机性的裂纹扩展失效功能函数 ,提出了亚表面裂纹扩展寿命计算方法。用 Hasofer- L ind方法分析某粉末冶金涡轮盘裂纹扩展失效概率 ,通过敏感性分析指出提高发动机可靠性的主要途径 ,具有工程指导意义。并用蒙特卡罗法和β球法进行验证 相似文献
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针对KTA50发动机在使用中出现缸盖裂纹较多的现状,详细分析了造成缸盖裂纹的原因,并在设备操作使用和维护保养等方面提出了预防措施,为降低发动机维修成本提供技术支持与借鉴。 相似文献
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《Mechanical Systems and Signal Processing》2007,21(1):502-513
A new model for vibration analysis of a crankshaft with a slant crack in crankpin is proposed, and the influence of crack depth on the transient response of a cracked crankshaft is investigated. A slant cracked shaft element is developed by deducing the local flexibility due to a slant crack. The frequently occurred slant crack in crankpin is studied, and a new finite element model of crankshaft including the slant crack in crankpin, which combines the slant cracked shaft element and Timoshenko beam elements, is derived. The support of engine block and the switching behaviour of the crack are considered, and the non-linear equation of motion for cracked crankshaft-bearing system is set up in a rotating coordinate system. The motion of a crankshaft of a four in-line cylinder engine with and without an initial crack is simulated. The influence of the crack depth on the transient response is investigated. The numerical simulation demonstrates that the current model is valid for simulating the motion of cracked crankshaft system. The results show that a useful foundation is laid for crack detection of crankshaft. 相似文献
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汽车发动机维修是一项既考验专业技能又突出实践经验的工作.汽车发动机故障原因比较多,对于不同类型的发动机故障需要采取相应的诊断技巧与维修方案.本文结合多年实践调查,以汽车发动机点火故障、发动机抖动故障、发动机烧机油故障以及冷却液故障为例,详细分析诊断技巧与维修经验,以此为今后实践教学提供经验. 相似文献