Subjects: Geosciences >> Space Physics submitted time 2017-03-10
Abstract：传统接触测量的方法无法对高温范围的金属材料的热膨胀系数进行测量，结合静电悬浮无容器技术和图像测量方法， 通过半导体激光器加热悬浮的样品，在加热的过程中利用CCD采集悬浮样品的图像，采用方向梯度算法提取图像中样品的边缘， 并利用球谐函数拟合样品的体积，计算得到材料在不同温度下的热膨胀系数。采用纯锆的金属材料样品进行实验，在 750-1800℃的温度范围内，测量得到固态样品锆的热膨胀系数随温度变化的表达式，验证了该测量方法的有效性和精度。
Peer Review Status:
Awaiting Review
Subjects: Geosciences >> Space Physics submitted time 2017-03-10
Abstract：随着材料研究逐渐深入，材料制备和材料分析的方法越来越重要，然而，一些重要的物理性质是开展相关研究的基础。 由于一些材料熔点高、难熔化，同时，传统手段无法避免容器壁的污染，或者无法在真空条件下进行试验避免气体的污染， 或者由于实验性质原因只能测量特定的材料；这些方法很难测量材料在高温下过热过冷阶段的热物理性质。本文系统介绍了 静电悬浮技术这种新型的实现深过冷的方式，达到对材料热物理性质进行测量的目的。静电悬浮技术使样品在两极板间悬浮， 在悬浮的状态下采用激光对样品进行加热，使材料达到高温熔化，同时进行热物性的测量。本文对比了几种实现测量典型热 物理性质的方法，了解静电悬浮的优势，以及详细地介绍了静电悬浮技术对材料的熔体密度、热膨胀系数、表面张力和粘度 系数以及比热的测量。
Peer Review Status:Awaiting Review
Subjects: Geosciences >> Space Physics submitted time 2017-03-10
Abstract：针对大型高海拔空气簇射观测站水基切伦科夫探测阵列测距系统，提出了一种基于超声波测距技术的测距系统，并完成软硬件设计。该系统的下位机以LVCN318和PLC为核心，主要完成数据的采集与处理，上位机部分基于OPC技术，实现上位机与PLC的通信以及数据的显示与存储。基于该系统分别进行了障碍物测距与液位测量实验，实验研究表明，液位测量与障碍物距离测量的误差皆小于11mm，在LVCN318的误差范围内，为水基切伦科夫探测阵列测距系统的设计与研制奠定了基础。
Peer Review Status:Awaiting Review
Subjects: Geosciences >> Space Physics submitted time 2016-05-13
Abstract： The facility for combustion experiments in space is lightweight, small sized and multi- functional. In this paper, a prototype system used for flame structure display and temperature measurement is presented, which combined the schlieren method, rainbow schlieren deflection method and differential interference method. It is also lightweight and small sized. As for the prototype system, the flame structure display function was checked by schlieren method in microgravity drop tower, and the temperature measurement function was checked by rainbow schlieren deflection and differential interference method under normal gravity condition. Results show that the resolution of flame structure was not less than 1 mm, and temperature field measurement was accurate with relative error smaller than 2%. Such prototype system is important to the promotion of space combustion science experiment technology and will be beneficial to the future combustion experiments in space.
Peer Review Status:Awaiting Review
Subjects: Geosciences >> Space Physics submitted time 2016-05-13
Abstract： A measurement and control system of three-dimensional(3D) position information of electrostatic levitation based on position sensitive detector(PSD) is setup and structure of PSD and position measurement and control principle of electrostatic levitation are analyzed.Output signal of PSD is processed by STC12C5A60S2 MCU,corresponding relationship between suspension sample position information and output voltage of PSD is obtained,and communication between MCU and upper PC,data analysis and processing,and position control on levitation sample are realized.Use zirconium materials to carry out suspension experiment and test results indicate that the system can realize non-contact measurement of sample position information and stable suspension of sample,and it has advantages of stable operation and reliable detecting data,and so on,and this measurement system laid foundation for material suspended heating and undercooling research.
Peer Review Status:Awaiting Review
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