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31.
The dynamic response of the rotor depends on not only itself but also the dynamical characteristics of the structures that support it. In this paper, the coupling vibration characteristics of the rotor and supporting structure are studied using one simple rotor-supports model firstly, and then the dynamic stiffness of the typical supporting structure of an aero-engine is investigated in use of both numerical and experimental methods. While, one simulation strategy is developed to include dynamic... 相似文献
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As multi-discipline coupling and components interference often affect the aircraft configuration decision-making and analysis during conceptual design process, this article presents an approach of multidimensional game theory based on aircraft components to deal with this problem. The idea is that the configuration decision-making process is regarded as the game for different disciplines and technologies, and the aircraft components are players. The payoff function with highest total gain means that according to the game protocols and multidimensional theory, the optimal aircraft configuration within the strategy set will be chosen. The decision-making model is applied to conceptual design process of the high altitude long endurance (HALE) unmanned aerial vehicle (UAV) based on the assessment of technological risk. The obtained optimum configuration is quite consistent with the current HALE UAV development trends. Thus, taking into account the coupling and interference factors, the multidimensional gaming model based on aircraft components will be an effective analysis method in the decision-making process of aircraft optimum configuration. 相似文献
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飞机上耐高液(气)压部附件易发生泄漏破损等问题,对飞机的安全运行至关重要。本文开发了一种测试系统,以气体和液体为介质,以飞机蓄压器为例,通过压力检查、泄露测试、摩擦阻力测试,检测待测部件是否合格。检测结果证明,该测试系统可作为飞机机械系统耐高液(气)压部附件检测的一种参考方法。 相似文献
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Rotating experimental investigations were carried out to study the oil sealing capability of two different floating ring seals in cold/hot state for aero-engine. High-speed Floating Ring Seal(HFRS) is a seal with the inner diameter of 83.72 mm and maximum speed of 38000 r/min, and Low-speed Floating Ring Seal(LFRS) is another seal with the inner diameter of 40.01 mm and maximum speed of 18000 r/min. In hot state, sealing air with the temperature of 371 K and oil with the temperature of 343 K was employed to model the working conditions of an aero-engine. Comparisons between floating ring seal and labyrinth seal were done to inspect the leakage performance.More attention was paid to the critical pressure ratio where the oil leakage began. Results show that the critical pressure ratio in cold state is obviously larger than that in hot state for both seals. An underlying sealing mechanism for floating ring seal is clarified by the fluid film, which closely associates with the dimensionless parameter of clearance over rotating diameter(2 c/Dr). Another fantastic phenomenon is that the leakage coefficient in hot state, not the leakage magnitude, is unexpectedly larger than that in cold state. Overall, the leakage performance of the floating ring seal is better than the labyrinth seal. 相似文献
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以对转压气机为研究对象,在数值方法校验的基础上,应用全通道定常流场分析手段计算了对转压气机不同周向畸变条件下的三维流场,获取了周向总压进气畸变对该压气机性能以及流场结构的影响效应,确定了对转压气机的临界畸变角,分析了不同畸变强度对压气机性能的影响规律,探讨了周向总压畸变在对转压气机中的发展演化过程。结果表明:(a)所研究的对转压气机临界畸变角约为72°,略高于传统动-静叶排交替的压气机临界畸变角;(b)相比均匀进气工况,当畸变指数为0.24时,对转压气机失速点压比和失速裕度分别下降3%和9.6%,当畸变指数为0.5时二者分别下降8.3%和19.8%;(c)未畸变区与畸变区流体之间存在的压力梯度影响转子叶片相对来流速度。进入畸变区叶片来流相对速度减小,负荷降低,退出畸变区叶片来流相对速度增大,负荷增大;(d)上游转子使得畸变水平提高,下游转子反向旋转效应抑制了来流相对速度变化趋势,增强了气流在其叶片通道中的掺混,使得畸变水平有所下降。 相似文献
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在分析现役老龄化舰载直升机动部件载荷特点的基础上,结合直升机所处的海洋腐蚀环境,讨论了舰载直升机的损伤类型和损伤容限寿命管理方法在其寿命分析中的应用,比较了损伤容限法应用于舰载直升机动部件与应用于固定翼飞机的不同点,重点讨论了损伤容限方法应用于工程实践亟待解决的关键技术。 相似文献
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In this paper, harmonic balance method, exact formulation and numerical simulation method are adopted to study the effects of different friction stiffness on the stability of 1.5 degrees of freedom aeroelastic system. On this basis, the expressions of input energy and dissipated energy are deduced, and the energy method is used to reveal the mechanisms of the stable boundary and unstable boundary existing in the system and the effects of different friction stiffness on the stability of the system. Studies have shown that the stability region and the critical aerodynamic damping ratio of the system rise with the increase of the friction stiffness, while the friction stiffness has little effect on the stability boundary. In the analysis of the stability of system, the results of harmonic balance method, exact formulation and Newmark of numerical simulation method are in good agreement. Compared with exact formulation and numerical simulation method, the concept and conclusion of harmonic balance method are simple in the system stability analysis. 相似文献