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	Experimental study of heat transfer enhancement for molten salt with transversely grooved tube heat exchanger in laminar-transition-turbulent regimes 期刊论文 OAI收割 APPLIED THERMAL ENGINEERING, 2018, 卷号: 132, 页码: 95-101 作者: Chen, YS; Tian, J; Fu, Y; Tang, ZF; Zhu, HH \| 收藏 \| 浏览/下载：26/0 \| 提交时间：2018/09/06 Concentric Tube Corrugated Tubes Region Flow Roughness Reactor Channel Wall
	Study on ultra-light secondary baffle for coaxial two-mirror telescope (EI CONFERENCE) 会议论文 OAI收割 2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China 作者: Zhang L.; Zhang L. 收藏 \| 浏览/下载：78/0 \| 提交时间：2013/03/25 The coaxial two-mirror telescope consists of two mirrors facing each other. Classical two-mirror arrangements are Gregorian and Cassegrain. These systems are usually applied to space telescopes and often have optical baffles to prevent stray light from entering the focal plane. The optical baffles consist of concentric rings suspended between the secondary and the primary mirror. The secondary baffle for a large two-mirror optical system is designed and analyzed in this paper. According to mission of a telescope the structure should have high stiffness and high reliability and light weight. Compared with invar aluminum alloy and titanium alloy carbon fiber composite is currently the best material in terms of weight-to-strength ratio. It also has advantages of high temperature tolerance and low thermal expansion. So carbon fiber composite is chosen as material to meet requirements of the coaxial telescope. In this paper optimization method based on finite element analysis (FEA) is used for design the secondary baffle. Minimum weight of the baffle is chosen as an objective function. Thicknesses of former tube and vanes are chosen as variables. Analysis results show that the designed secondary baffle has maximum diameter of 180mm total length of 120mm and weighs 142g. And its fundamental frequency reaches 651Hz. Therefore the baffle has many advantages such as ultra-light weight high stiffness and dimensional stability etc. The optimization method and the baffle design can be helpful to other coaxial telescopes such as Cassegrain Gregorian and their subdivisions. 2012 IEEE.
	Method for the fabrication of isometric mesh on the concave of a spherical substrate (EI CONFERENCE) 会议论文 OAI收割 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies - Advanced Optical Manufacturing and Testing Technologies, November 2, 2005 - November 5, 2005, Xian, China 作者: Feng X.-G. 收藏 \| 浏览/下载：39/0 \| 提交时间：2013/03/25 Metallic mesh has been widely used in electromagnetic interference windows. While the duty ratio of curved mesh equals to planar mesh' the theory of planar mesh may be applied to curved mesh according to equivalent-circuit model. So the idea that latitude lines intersect latitude lines to form isometric mesh on the concave of a sphere is put forward and the method of fabricating the mesh by concentric optical scan is introduced. The movement parts of equipment consist of an erection turning a horizontal dividing and a pitching dividing spindle. Firstly a spherical substrate is fixed on the horizontal dividing spindle that has been set horizontally on the erect turning spindle the substrate revolves around the axis of the erect spindle the tube of object lens that is fixed on the pitching dividing spindle steps at pitching direction and a revolving circuit of the substrate corresponds to a step of the tube. Gradually a set of latitude lines is attained. Afterward the substrate makes a quarter turn around the horizontal spindle another orientation latitude lines are also gained. Thus the isometric mesh on the concave of a spherical substrate is gained. The process comprises surface cleaning coating photoresist laser direct writing development evaporated film dissolving photoresist and plating. The fabricated spherical mesh has a line width of 7 m and a period of 600m. Experiment shows that infrared transmission and electromagnetism shield efficiency of the metallic mesh are relatively consistent with theoretical value.