【作者】 蔡璐璐；

【导师】 王子才； 王玉田；

【作者基本信息】 燕山大学 ， 检测技术及自动化装置， 2010， 博士

【摘要】 温度是确定物质状态最重要的物理量之一,在热力学、流体力学、传热学、物理、化学、冶金等学科中所研究的基本规律都与温度有密切关系,所以温度的测量与控制在国防、军事、科学实验及工农业生产中具有十分重要的作用。随着科学技术的发展,传统的接触式测温技术和非接触式测温技术由于其自身的缺点,已无法满足科技发展的需求,因此开展新原理温度计的研制、多光谱辐射测温技术的研究是目前国内外研究的重要方向。本文主要对所设计的基于黑体腔特性的光纤高温测试系统的理论和实验展开研究。根据黑体辐射换热理论,建立了黑体腔传感器积分发射率和表面有效发射率的数学模型,以圆柱形黑体腔传感器为例,讨论了腔壁、腔盖和腔底各类型角系数的表达式及其奇点分布,分析了黑体腔几何尺寸对腔表面各点有效发射率分布的影响。在此基础上,引入半照区角系数模型,结合黑体腔表面有效发射率的分布规律和探测器尺寸、距离等参数,对黑体腔积分发射率的影响进行了详细的讨论和分析,得出了圆柱形黑体腔传感器设计的参数配置。提出应用可调谐光纤光栅滤波器实现波长选择的比色式光纤辐射温度测量方案。根据模耦合理论,建立了光纤光栅反射谱模型,分析了影响其反射谱特性的各个参数;根据光栅的弹光效应对光纤光栅的轴向均匀应力特性进行了讨论,建立了相应的传感模型。在此基础上,设计了光纤光栅可调谐滤波器的结构,同时针对比色测温方案,详细讨论了光栅中心波长、带宽等参数对不同温度段测量灵敏度的影响,得出了光纤光栅参数最佳选择。对波长选择的比色式测温方法进行了理论分析。通过对比同一温度下,小范围内不同波长的辐射功率和不同发射率时的辐射功率特性,确定了影响辐射功率的主要因素,进而结合比色测温方法,论证了波长选择的比色式测温方案的优点和可行性;根据测量所得温度信号的噪声特征,引入了小波消噪方法,详细分析了小波消噪的具体过程和实现方法,设计了相应的算法程序,在理论上论证了应用的可行性。设计了基于黑体腔特性的光纤高温测试系统,对系统的硬件组成和软件设计进行了介绍。对光纤辐射测温系统进行了静态响应和动态响应实验,分析了误差产生的主要原因。通过动态响应实验论证了应用小波滤波方法对动态温度信号进行消噪的可行性。在此基础上,对光纤高温测试系统进行了静态响应和动态响应实验。通过对高温测试系统的研究与分析,仍存在需要进一步研究和解决的问题:黑体腔表面温度不均匀时,其表面各点有效发射率产生变化,导致黑体腔积分发射率变化,即黑体腔表面温度不均匀对积分发射率的影响;黑体腔在高温测量过程中存在着热量的传递,研究黑体腔积分发射率动态变化特性;研究提高黑体腔传感器动态响应的材料和方法。更多还原

【Abstract】 Temperature is one of the most important physical quantities determining the state of matter. The basic rules, researched in the disciplines of thermodynamics, hydromechanics, heat transfer theory, physics, chemistry, and metallurgy, have the close relation with the temperature. So temperature measurement and control play very important roles in the national defense, military, scientific experiments, industrial and agricultural production. With the development of science and technology, a number of common temperature measurement technologies, such as contact temperature measurement technology and the non-contact ones, have been unable to meet the needs of scientific and technological development. Hence, researches on the thermometer principle and multi-spectral radiation temperature measurement technology are the important direction at home and abroad. This paper mainly studies fiber high temperature measurement system theoretically and experimentally, which is based on blackbody cavity characteristic.According to the blackbody radiation heat transfer principle, this paper established the mathematic model of blackbody cavity sensor integrated emissivity and the effective emissivity of the surface. And discuss the all kinds of equation on the angle factor and singular point distribution. Then analyze the effects of blackbody cavity geometry size versus the point distribution of effective emissivity of the surface on blackbody cavity. Based on this, we obtained the optimum parameters for the sensor selecting.The scheme of colorimetric fiber temperature measurement system is presented, which implements wavelength selection using tunable FBG filter. According to model coupling theory, the reflective spectrum of FBG is established and corresponding parameters are analyzed. In the same way, according to elastic-optic effect, the corresponding sensor model of FBG uniform stress in the axial direction is established. On this basis, the structure of FBG tunable filter is designed, and the best choice of FBG parameters are obtained.The colorimetric temperature measurement method, based on the wavelength selection, is analyzed theoretically. By comparing to the characteristic of the different radiation power and emissivity, at the same temperature the key effective parameters of radiation power are determined. The merits and feasibility of the wavelength selection colorimetric temperature measurement scheme are demonstrated. According to the noising characteristic of the measured temperature signal, the concrete process and implementation of wavelet de-noising are analyzed. At the same time, the corresponding algorithm program is designed, who’s the feasibility of application demonstrated theoretically.The filter high temperature measuring system, based on the blackbody cavity characteristic, is designed. And the hardware system and software design are introduced. By stationary and dynamic experiments to the fiber radiation temperature measuring system, the reasons of the system error are analyzed simultaneously. The feasibility of denoising the dynamic temperature signal using the wavelet filter method is demonstrated by the dynamic experiment. Based on it, Optical fiber high temperature measurement system is tested by stationary and dynamic experiments.According to the researches and analysis on high temperature test system, further study and the solution question still exist.When the temperature of the black body cavity surface is non-uniform, its superficial effective emissivity of each spot has change, leading to the integral emissivity of blackbody cavity variation, namely non-uniform black body cavity surface temperature affects the integral emissivity. The black body cavity has thermal transmission in the high temperature measuring process. Researching the dynamic change characteristic of the black body cavity integral emissivity, and the material and the method of enhancing dynamic response of the black body cavity sensor are necessary.更多还原