排序方式: 共有47条查询结果,搜索用时 31 毫秒
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密封材料空间环境失效分析 总被引:5,自引:0,他引:5
吴国庭 《中国空间科学技术》1997,17(6):40-44
对空间环境造成载人航天器密封材料的各种失效机理进行了分析。材料低温脆化,高温时表面脆化;真空时材料内挥发成份的溢出,使材料渗透性增大;辐照使密封件失去弹性:这些是空间环境中温度、真空和辐照使密封失效的主要原因。真空条件下,密封件挥发成份中的可凝物在光学元件表面的凝聚从而破坏表面光学特性,是密封设计中一个值得重视的现象。 相似文献
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串联密封系统泄漏率的测定 总被引:3,自引:0,他引:3
从理论上讨论了用常规氦质谱仪检漏方法测定两密封件串联密封的气路系统各密封件“单密封”泄漏率的问题。给出了解析结果, 所得出的结论应用在工程实践中有利于提高产品质量, 具有经济价值。 相似文献
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本文是一篇关于箭载电子仪器结构密封设计的文章,是多年来结构设计和实践经验的总结.文中对密封原理、密封装置的设计要点、密封圈和固紧螺钉的选择、壳体受压变形情况诸方面进行了论述. 相似文献
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侯珍秀%余志洋%刘云猛%王立峰%吴福迪 《宇航材料工艺》2007,37(6):15-20
为研究X形丁腈橡胶密封件在往复轴的静压工作状态和往复工作状态下都能可靠地密封,利用大变形非线性有限元方法对此密封机构的各种工作状态进行了分析,并讨论了不同状态下,各应力状态的分布规律和各应力随不同工作压力的变化规律。结果表明:无论何种工作状态,其高应力区均分布在密封圈非压力侧凹圆处或间隙挤出处,且上行时的接触应力大于下行时的接触应力。 相似文献
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《中国航空学报》2021,34(4):320-331
The windage loss caused by protrusion in a rotor–stator cavity has been studied in detail, and there are abundant fitting formulas that have been summarized to calculate the moment coefficients. Some other theorists have emphasized its effect on the sealing efficiency, proposing that installation of protrusion could alleviate gas ingestion. However, the protrusion shape which is an influential factor on the sealing efficiency has not been focused in previous research. Using the experimental method of measuring CO2 volume fraction, cavity pressure, and power consumption, we investigated the effects of several typical protrusion shapes on various parameters for two sealing structures, in order to obtain the optimal shape. Results showed that a variation of the protrusion shape had little impact on the static pressure, but the total pressure and the sealing efficiency increased in different degrees. Furthermore, even though the hexagon shape resulted in the highest sealing efficiency, we observed that the drop shape had the best overall performance in all of the eight models, which could result in higher efficiency of the turbine cavity. The combination of a radial seal structure and protrusion could improve sealing efficiency better. 相似文献