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介绍了国内航天器应用的泄漏检测技术及国外先进的航天器泄漏检测技术和泄漏检测标准;分析了航天器泄漏检测技术的发展趋势。 相似文献
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聚四氟乙烯软管内管在多次使用后发生渗漏.采用体视显微镜和扫描电镜对渗漏软管及复现试验软管进行观察与分析.结果表明:软管内表面存在制造工艺缺陷,在多次使用过程中在较高的油压作用下缺陷处沿厚度方向发生低周疲劳扩展,局部区域形成穿透损伤,导致软管发生渗漏. 相似文献
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检漏间是飞船在航天发射场进行检漏分析的重要设施设备。在对飞船检漏间的基本结构组成进行分析的基础上,建立了基于小孔泄漏模型的飞船检漏间泄漏过程数学模型,并进行了仿真分析。同时,对飞船检漏间迷宫式密封结构的泄漏途径进行了分析,在此基础上,建立了飞船检漏间泄漏因素的故障树模型。依据该模型,通过分析排查试验,明确了泄漏故障发生的具体位置、泄漏原因以及泄漏机理。在采取针对性维修措施的基础上,飞船检漏间漏率指标达到了平均<100Pa/24h的范围,满足了设计指标<150Pa/24h的要求。实际泄漏检测试验表明:上述方法简单、有效。 相似文献
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William F. Dempster 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
Processes which produce slow changes in air composition in a closed ecological system (CES) may not be noticed if the leak rate of the CES is significant. Dilution of the system’s air with outside air can mask these processes. A tightly closed CES provides the opportunity for slow changes to accumulate over time and be observed and measured. Biosphere 2 (volume 200,000 m3) had a low leak rate of less than 10 percent per year. Oxygen declined slowly at varying rates reflecting seasonal influences, which averaged to about 140 ppm per day during the first 16 months of the two-year closure. Computer simulations of the observed rate of oxygen loss combined with other hypothetical leak rates suggest that the decline would have been hidden by a leak rate as low as one percent per day. Sealing Biosphere 2 involved rigorous design specifications and inclusion of two expansion chambers (called “lungs”) to accommodate expansion/contraction of the atmosphere, which enabled limiting the pressure difference between inside and outside atmospheres to the range of ±8 Pa (0.08 mBar). Measurement of leak rate was by two methods: the first, measuring the rate of deflation of the lungs while holding a constant elevated pressure differential enabled calculation of an estimated leak rate within the usual operating pressure differential range; the second was to measure the progressive dilution of trace gases spiked into the atmosphere. Both methods confirmed leakage to be less than 10 percent per year. Operational data from the 40 m3 Laboratory Biosphere is used to illustrate how normal variations of temperature, humidity and barometric pressure would combine to force leakage and rapidly dilute the internal atmosphere if it were not equipped with a lung. It is demonstrated that very high degrees of closure for a CES enable experimental observation of small imbalances in atmospheric cycles or slow accumulation of trace gases that could otherwise be masked by dilution with atmosphere external to the CES. 相似文献
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动态比较法校准正压漏孔的漏率 总被引:4,自引:0,他引:4
介绍了校准正压漏孔漏率的动态比较法,可以校准的正压漏孔漏率范围为1×10-4~1×10-7Pam3/s。参考漏孔动态比较法是用一只漏率已知的正压漏孔作参考标准,分别让示漏气体通过参考正压漏孔或被校正压漏孔后,在内充大气的累积容器中累积不同的时间,产生大致相同的示漏气体增量;静态膨胀后,测量它们在动态流量法系统中产生的动态平衡分压力,再进行线性近似比较计算出被校正压漏孔的漏率。定量气体动态比较法是采用定量的示漏气体作参考标准,替代参考漏孔动态比较法中示漏气体通过参考正压漏孔后在累积容器中的累积量。 相似文献
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针对大型卫星在总体装配生产过程中需要对其密封性能、仪器的安装精度、质量特性性能指标进行准确测试的要求,研制了单点、总漏率四极质谱和氦质谱测试系统及相应的标定装置,实现了大型卫星电推进系统密封性能的准确测试和实时比对校准;研制了基于三坐标转换机的大载荷质心、转动惯量集成质量特性测试系统和直接比对校准转子,单次安装测出所有轴向的质量特性参数;研制经纬仪、激光跟踪仪联合高精度角度和位置安装精度测量系统,研制基准转换器,实现测量坐标系的转化和测量精度的实时校准。完成了数个大型卫星总装过程的专业测试工作,保证了大型卫星的总装过程装配质量。 相似文献
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通过对常用的大气压累积法氦质谱检漏过程的理论分析,指出了该方法可能的系统误差。分析认为:对于表面材料粘附几率较小的被检件,可以采用常用的大气压累积检漏方法进行总漏率的测量,而对于表面材料粘附几率较大的被检件( 如表面存在大量的有机材料等) ,如采用常用的大气压累积检漏方法进行总漏率的测量必将带来较大的系统误差。最后,提出了消除该系统误差的等分压常压累积检漏技术,并与常用的常压累积法检漏技术进行了比较。 相似文献
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漏率与压力关系的研究 总被引:8,自引:1,他引:7
在高压密封系统中,漏率与压力的关系,目前仍然处于探索之中。对不同的刚性物理漏孔进行了不同压力状态下的漏率试验,发现了漏率的函数关系。在试验的基础上,经理论分析,验证了其规律的正确性。同时,发现随着漏孔长度的减少而压力指数变大的规律。 相似文献