非接触红外测温技术在快速成形领域的应用研究

深入研究再制造成形过程中温度场分布及变化对实现零件的成形与组织性能一体化控制具有重要意义.分别阐述了非接触红外测温技术常用设备(包括亮度测温仪、比色测温仪和红外热像仪)的工作原理及在再制造成形领域中的应用进展,并展望了非接触红外测温技术的发展方向.     

内调制多色比色测温系统

发射率表征待测体与黑体的辐射强度之比,它与材料的性质、表面状态密切相关,随时间变化而变,并显著影响测温精度。为此提出了一种新的多色比色测温方法,该方法可以对待测体的发射率进行实时修正,具有自适应的特点,使测温仪可以快速、准确地测量温度。采用这种测温方法研制出新型的内调制多色比色测温系统,测温仪用内调制光电探测器作为探测单元,探测器能将恒定的光信号转变为交流电信号输出,便于信号放大和消噪,有效地提高了系统的信噪比。在1050～1650℃范围,测温最大误差为6．2‰。     

红外测温仪测量准确度的影响因素分析及修正方法

从红外测温原理出发,介绍了红外测温仪的构成与特点,分析了环境、发射率以及距离等因素对其测量准确度的影响。通过采用实验数据拟合曲线对测温结果进行修正的方法,重点分析了距离因素对红外测温仪测量准确度的影响。其中以有效测温距离作为分界点,分段得到了拟合曲线与修正公式。实验结果表明,此方法能够有效提高红外测温仪测量结果的准确度,具有较高的实际使用价值。     

辐射测温仪表的原理和应用

辐射测温仪表是一种被广泛使用的非接触式测温仪器。本文概述辐射测温仪表的工作原理和结构特点,着重叙述辐射测温仪表的有效发射率设定、距离系数选择和环境条件对温度测量结果带来的影响,并介绍了辐射测温技术的应用和发展。     

红外测温仪的研究

介绍了非接触式测温法的优势和一种常用的非接触式测温的应用之一：红外测温仪的测温原理,指出了红外测温系统的总体结构和信号放大、带通滤波、相敏检波等各部分电路组成的特点与要求。     

漫谈红外辐射测温仪

介绍红外辐射测温仪的测温原理、特点和广应用及检定状况,辐射温度计检定中存在的问题.     

红外测温技术在变电运行中的应用分析

红外测温技术是相对于传统的测温仪更加科学的一种测温技术,本文从红外线测温技术的原理、与传统测温仪的区别以及红外线测温技术的应用三个方面介绍了其在变电系统中发挥的重要作用。     

比色光纤测温传感器设计

本文介绍了比色测温原理,提出了一种比色光纤测温传感器的设计方案,并通过实验验证了方案的可行性。该设计方案成本低、精度高,具有一定的应用价值。     

JJF1379-2012《热敏电阻测温仪校准规范》解读

正热敏电阻测温仪由热敏电阻传感器和显示仪表组成,测温仪的工作原理是利用热敏电阻随温度变化而变化的特性进行测温,其特点是响应速度快、感温元件小、在窄温区内测量准确度高。一、修订原因及目的随着科学技术的发展,热敏电阻测温仪广泛应用于生产、生活、科研等各个领域。各种类型的热敏电阻测温仪产品不断出现。通过调研,温度范围为-80℃~     

红外测温仪的工作原理及检定数据处理方法探讨

本文主要介绍红外测温仪的工作原理、特点、阐述如何进行精确测温及详细探讨检定后的数据处理方法.     

一维高温温度场测试技术

研制了可对一维高温温度场进行测量的扫描式高温计．该扫描式高温计分为旋转扫描式光学系统、比色高温计和上位机三个部分．在分析温度场测量要求的基础上,推导了比色光学高温计的测量原理,建立了数学模型．基于光的反射理论,研究了旋转扫描式光学系统与一维温度场之间的运动关系．利用光学光纤将光学探头接收的光信号进行远距离传输,增加了测量的便利性和整套装置对测量环境的适应能力,专用的微型工控及控制系统提高了这套装置独立工作及与其他设备进行协调合作的能力．对比色高温计的波长函数和测量精度进行了标定,校验结果表明在800℃～3500℃范围内的测量精度为1％．最后,利用扫描式高温计对棒状碳／碳试样的轴向温度场进行了测量,通过几个固定点温度对一维温度场的测量精度进行了校验,最大测量误差为3．09％．     

高频焊管焊接点温度的传感及其模糊控制

针对高频焊管焊接区的测温条件 ,采用比色测温仪检测焊接点温度 ,有效地提高了测温信号的稳定性 .应用模糊控制方法调节高频感应电源的输出功率 ,控制焊接温度 ,同时设计了三种调节功能对控制效果作进一步的改善 ,实现了高频焊管温度的稳定控制过程 .     

基于波长函数的辐射温度计一点标定法及其精度的理论估计与实验验证

叙述了通过测量辐射温度计波长函数和一个温度点的输出信号,从而得到辐射温度计全量程标定方法估计了各项误差源对温度标定误差的影响,给出了重要结论。进一步以某多波长高温计为例,在黑体炉标定实验基础,进行了一点标定法的验证,结果证明该方法可以得到较高精度的标定。     

航空发动机热端表面温度场测量

航空发动机热端温度场的测量和监视对延长发动机的使用寿命具有重要意义.文章简要介绍了目前采用的各种温度测量方式,如热电偶、光电高温计、红外热像仪和示温漆,并详细介绍了多波长温度测量和谱色温度测量两种新型的温度测量方法.两种方法大大降低了温度测量对被测物体表面发射率的依赖性,适用于1000～3000℃温度范围内高温物体表面温度的测量.     

Filter Radiometers as a Tool for Quality Assurance of Temperature Measurements with Linear Pyrometers

Measurements made with a pyrometer are vulnerable to errors if the pyrometer is misaligned, inaccurately characterized, or malfunctioning. In this work, thermodynamic temperatures between 1,373 and 1,773 K were studied by measuring a variable-temperature blackbody with a linear pyrometer and four absolutely characterized filter radiometers. The filter radiometer measurements were done in the irradiance mode. In the first set of measurements, there was a 3–5 K difference between the pyrometer and the filter radiometer data. The cause was tracked to malfunctioning of the pyrometer, which was afterwards sent for repair on the basis of these results. In the second set of measurements, with the repaired pyrometer, the agreement of the temperature results was good, the mean difference being −0.41 K with a standard deviation of 0.52 K. The differences between the pyrometer and the filter radiometer temperature measurement results showed no temperature dependence. It was concluded that the filter radiometers used in the irradiance mode provided a straightforward method for the quality assurance of pyrometers.     

基于BP神经网络的黑体炉温度时序预测模型的建立

黑体炉作为标准黑体辐射热源,特别适合供多种非接触式测温仪表如光电高温计、光学高温计、辐射高温计等的分度和校验之用.但黑体炉在运行时无法预知温度的具体数值,这为实验和标定带来了诸多不便.文章在神经网络的基础上,建立了黑体炉温度时序预测模型.结果表明:神经网络不但能对黑体炉温度进行预测,而且比实际的测温仪表的精确度高出很多.     

Spectral-ratio pyrometer for measuring the temperature of carbon steels

The salient features of a spectral-ratio pyrometer for measuring the true temperature of metal steam pipes in the range from 700 to 1100°C are considered. Experimental data on the monochromatic emissivity of a carbonsteel surface during oxidation at 1000°C are given. Optimal spectral regions are chosen for a spectral-ratio pyrometer, the pyrometer is described briefly, and the results of tests with the instrument are reported. Translated from Izmeritel'naya Tekhnika, No. 2, pp. 23–25, February, 1997.     

The effects of gas pressure in plasma surface alloying process on testing accuracy of the photoelectric pyrometer

In order to control the specimen temperature precisely in a plasma surface alloying process, the measurements obtained using a photoelectric pyrometer were compared with a thermocouple system. The effect of pressure on the accuracy of the photoelectric pyrometer is discussed. The results indicate that at a specific temperature, as the working pressure increases, a larger emission coefficient ε should be used to keep the pyrometer values consistent with those of the thermocouple, which is considered to give the real temperature. The value of ε increases by about 0.1 as the working pressure increases by 5-10 Pa. With this adjustment, the error of the pyrometer is within ±3°C.     

A triple-wavelength pyrometer that measures true temperature

A new triple-wavelength spectral-ratio pyrometer that measures the true temperature of thermal radiation by minimizing the equivalent wavelength is described. An algorithm of the operation of the pyrometer and the results of its use in ferrous metallurgy are presented.     

Error analysis of a ratio pyrometer by numerical simulation

A numerical method has been devised to evaluate measurement errors for a three-channel ratio pyrometer as a function of temperature. The pyrometer is simulated by computer codes, which can be used to explore the behavior of various designs. The influence of the various components in the system can be evaluated. General conclusions can be drawn about what makes a good pyrometer, and an existing pyrometer was evaluated, to predict its behavior as a function of temperature. The results show which combination of two channels gives the best precision.Paper presented at the Second Workshop on Subsecond Thermophysics, September 20–21, 1990, Torino, Italy.