共查询到19条相似文献,搜索用时 125 毫秒
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为了实现空间低温光学试验的深低温背景条件,对实现深低温环模技术以及氦冷却系统进行了探讨.通过分析得到以氦循环方式建立的20 K稳定深低温冷黑背景是最为合适的低温光学试验背景环境.该系统是由氦液化系统配合相应冷氦分配装置以及终端冷舱组成密闭循环系统.氦液化系统是基于由布雷顿循环和焦耳-汤姆逊作用组合而成的克劳德循环,它能持续提供一定流量和压力的液氦或冷氦气作为循环系统中制冷工质,从而为试验提供稳定的深低温环境. 相似文献
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低温真空腔体结构设计及传热分析 总被引:1,自引:0,他引:1
为适应未来航天低温光学系统的需要,研制了1套测量光学元件低温场和低温变形的系统。该系统由真空机组、低温真空腔体、防振系统、测量装置等主要部分组成。其中低温真空腔体是该系统中关键的装置,为光学元件的低温真空实验提供了必要的条件。对低温真空腔体的结构设计、真空度和传热进行了分析探讨,并且对梯形薄壁绝热支撑进行了详细结构热分析和COSMOSWORK软件的传热分析,结果表明可以满足低温真空的实验要求。 相似文献
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介绍了冷阱的结构及其设计计算,此冷阱是串联子低温再生及检漏真空系统的φ160管道上,分析了该冷阱的启动压强和液氮消耗量,得到了最佳的启动压强。 相似文献
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设计了1种新型辐射制冷器级间纤维支撑系统,介绍了其结构的设计,支撑材料的选择以及纤维接头的研制。利用MSC.Nastran有限元软件对系统进行准静态结构强度和纤维预紧力进行了分析。级间漏热的理论分析结果表明此纤维支撑系统为研制更大冷量的辐射制冷器提供了可能。 相似文献
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新风能耗为环控系统的主要能耗之一.为提高系统能效,提出了一种新风预处理系统,利用低辐射太阳能、夜空冷辐射与相变材料相结合的一种相变蓄能单元,其结构由空气换热器、水换热器和低温相变材料石蜡组成.通过该装置储存太阳和夜空冷辐射的能量,耦合空气、水换热器实现对空气的预热和预冷处理,并搭建实验台进行了相变过程、空气处理过程的冬... 相似文献
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北京正负电子对撞机重大改造低温传输管线支撑数值模拟 总被引:1,自引:1,他引:0
低温传输管线是北京正负电子对撞机重大升级改造(BEPCⅡ)中低温系统的关键设备之一.为了确保BEPCⅡ低温传输管线的设计质量,运用有限元软件包ANSYS对低温传输管线的支撑进行了热负荷的数值模拟,得到传输管线的漏热和支撑温度分布.设计了一种特殊的支撑结构来支撑多通道传输管线垂直段重量,并对该支撑进行了热和应力的数值模拟.最后确定了漏热、强度满足工程要求且结构设计简单的低温传输管线支撑方案,目前该支撑方案已经运用到实际传输管线的加工、制造中. 相似文献
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为匹配红外空间载荷低温光学镜头的光学性能,降低背景噪声,实现载荷高精度星上定标,研制了一种基于制冷机主动制冷的深低温星上定标黑体源装置(低温100 K工作),该星载黑体源装置由面黑体辐射体、低温制冷机主动制冷系统、冷量传输热管及精密测控温系统组成,通过载荷级真空辐射定标实验校验,最终实现红外遥感器对星上定标黑体源宽光谱(2~16μm)、高发射率(0.987)、深低温(100 K)的高精度定标源需求。该深低温星上定标黑体源可用于对极远极冷极弱目标探测的红外载荷星上辐射定标,其高精度、低功耗、通用性的工程化设计方法,为后续相关研究及推广提供技术支撑。 相似文献
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For many industrial, medical and space technologies, cryogenic fluids play irreplaceable roles. When any cryogenic system is initially started, it must go through a transient chill down period prior to normal operation. Chilldown is the process of introducing the cryogenic liquid into the system, and allowing the system components to cool down to several hundred degrees below the ambient temperature. The chilldown process is an important initial stage before a system begins functioning. The objective of this paper is to investigate the chilldown process associated with a flexible hose that was simulated by a channel with saw-teeth inner wall surface structure in the current study. We have investigated the fundamental physics of the two-phase flow and quenching heat transfer during cryogenic chilldown inside the simulated flexible hose through flow visualization, data measurement and analysis. The flow pattern developed inside the channel was recorded by a high speed camera for flow pattern investigation. The experimental results indicate that the chilldown process that is composed of unsteady vapor-liquid two-phase flow and phase-change heat transfer is modified by the inner wall surface wavy structure. Based on the measurement of the channel wall temperature, the teeth structure and the associated cavities generally reduce the heat transfer efficiency compared to the straight hose. Furthermore, based on the measured data, a complete series of correlations on the heat transfer coefficient for each heat transfer regime was developed and reported. 相似文献
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Yang-Hun Kim Su-Kil Lee Hyun-Man Jang Young-Woong Kim Keun-Tae Lee Chang-Youl Choi Cheol-Hwi Ryu Han-Joong Kim Si-Dole Hwang Hyung-Suk Yang Song-Ho Sohn Ji-Hyun Lim 《低温学》2012,52(12):661-666
The 22.9 kV/50 MVA AC HTS power cable system consisted of power cable with 410 m length and cryogenic system has been manufactured by LS Cable & System and installed in Icheon substation of KEPCO grid in the end of 2010. High temperature superconductor only appears the superconductivity at the constant temperate range. So in order to maintain the superconductivity, the cryogenic system is needed. The cryogenic system, the open-loop type, is consisted of the Pressure Control System (PCS), Gas/liquid separator, Circulation Pump, Decompression unit, Filter and so on. Decompression unit is a device that keeps the sub-cooled nitrogen by way of the latent heat of evaporation and includes the heat exchanger. The effectiveness-NTU method is used for the design of the heat exchanger. After installation of the cryogenic system on the site, the test of the cooling capacity of the cryogenic system and commissioning tests were performed. During the grid operation of the HTS power cable system, no major problems have been encountered to this point. The cryogenic system has been operated sufficiently to maintain a stable of the HTS power cable system. This paper will summarize the design of the cryogenic system and the results of the grid operation. 相似文献
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