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排序方式: 共有601条查询结果,搜索用时 31 毫秒
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为了提高导弹发射车液压系统的工作可靠性,按照三级层次结构,分析了液压系统的故障模式。以起竖液压系统为例,分析了监测信号类型及处理方法,研究了基于健康度的健康评估方法。利用健康度及其分级,量化评估液压系统健康状态,并针对非健康状态开展基于故障树的故障诊断与定位研究。 相似文献
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355.
《中国航空学报》2020,33(8):2099-2109
Bent inlet pipes are often used in centrifugal compressors due to limited installation space, and an understanding of the effect on compressor stability is essential for safety and durability. This paper firstly investigates flow instability behaviors in two compressors, one with a straight inlet pipe and the other with an S-shaped bent pipe. In detail, it analyzes the resulting flow fields, instability evolution paths and surge boundaries. The results show that the S-shaped pipe obviously affects the flow field at high mass flow rates, while reverse flow mainly influences the flow field at low mass flow rates. Reverse flow first occurs at certain flow passages with a high pressure difference that is predominantly decided by the volute rather than the S-shaped bent pipe. In addition, centrifugal compressors can tolerate reverse flow to some extent so that surge would not occur immediately if reverse flow occurs unless the reverse flow region extends circumferentially and radially to a sufficiently large size. Since the S-shaped pipe is not dominant in the creation and extension of reverse flow, it does not exacerbate the stability of the central compressor to a great extent. Last but not least, the S-shaped pipe is noted to delay the occurrence of surge at 90% rotating speed, which suggests the possibility of improving compressor stability with bent inlet pipes. This result differs from the conventional understanding that inlet distortion usually deteriorates compressor stability and emphasizes the particularity of centrifugal compressors. 相似文献
356.
从A320系列飞机液压系统的原理入手,分析了在A320飞机上使用应急液压堵头的可行性,详细介绍了如何使用应急液压堵头以及航空公司为预防突发性油液渗漏故障所采取的措施. 相似文献
357.
戈和伟 《西安航空技术高等专科学校学报》2015,(1)
针对双腔作动筒对隔套强度、耐磨性的要求,研制了双金属隔套,解决了单一材料隔套刚度与耐磨性难以兼顾的技术难题。提出的双金属溶渗技术工艺方法与检测方法,有效解决了两种金属的结合、钢材料热处理后晶粒度粗大、真空熔渗时表面易氧化等问题,确保了产品质量,为双金属溶渗技术跨领域使用提供了参考。 相似文献
358.
In this paper, a novel study on performance of closed loop pulsating heat pipe(CLPHP)using ammonia as working fluid is experimented. The tested CLPHP, consisting of six turns, is fully made of quartz glass tubes with 6 mm outer diameter and 2 mm inner diameter. The filling ratio is50%. The visualization investigation is conducted to observe the oscillation and circulation flow in the CLPHP. In order to investigate the effects of inclination angles to thermal performance in the ammonia CLPHP, four case tests are studied. The trends of temperature fluctuation and thermal resistance as the input power increases at different inclination angles are highlighted. The results show that it is very easy to start up and circulate for the ammonia CLPHP at an inclining angle.The thermal resistance is low to 0.02 K/W, presenting that heat fluxes can be transferred from heating section to cooling section very quickly. It is found that the thermal resistance decreases as the inclination angle increases. At the horizontal operation, the ammonia CLPHP can be easy to start up at low input power, but hard to circulate. In this case, once the input power is high,the capillary tube in heating section will be burnt out, leading to worse thermal performance with high thermal resistance. 相似文献
359.
张清 《长沙航空职业技术学院学报》2011,11(3):50-53
电传操纵系统通道故障灯亮灭是由监控电路根据各级表决故障信息判断产生,监控电路较复杂。飞机通电和供给液压时,通道灯时亮时灭,状态多种,是电传操纵系统故障监控电路作用的结果。阐述液压系统供压状态影响座舱ПУ-220/353操纵台通道灯亮灭的工作机理。 相似文献
360.