共查询到20条相似文献,搜索用时 62 毫秒
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介绍了一种传递标准钨带灯亮度温度的全自动检定装置,该装置满足JJG 110—2008《标准钨带灯》检定规程中对标准钨带灯检定的要求。研制的程控电源直流稳定度小于0. 02%/min,并且设计为数字电路、控制电路、交流电路及功率电路等功能互不干扰,结合软件实现标准钨带灯的自动检定,从而提高了检定质量及工作效率。 相似文献
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针对以精密钨带灯为标准器的精密光电高温计校准,介绍了光电高温计的工作原理、有效波长的概念和对高温计有效波长测量基本要求;详细阐述了采用钨带灯的直接比较分度法中灯电流的亮度温度波长的修正方法。基于高稳定度钨带灯物理模型计算了亮度温度-波长变化率,给出拟合公式。举例说明钨带灯电流的波长修正。定性分析了不同类型钨带灯物理模型差异对亮度温度-波长变化率的影响。 相似文献
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介绍了在2000年度全国大区级法定计量技术机构800℃~1700℃温度比对中,采用标准光学高温计及其本身有效波长,测量指定有效波长下高稳定度真空钨带灯亮度温度的一种更为合理的不确定度评定方法,同时给出评定结果和适用范围。 相似文献
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针对<标准钨带灯检定规程>、<标准温度灯检定规程>中关于分度点稳定时间的不同要求进行了分析,通过实验验证了800℃时稳定时间延长的合理性. 相似文献
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经典的短波高温修正模型不适用于中长波红外温度计的发射率修正和不确定度评定。采用有效亮度温度概念,得到了对于温度范围和测温波长具有广泛适用性的发射率影响模型以及具有简明物理含义的微差近似形式,包含了经典亮度温度理论中的发射率影响修正和环境辐射误差修正。定量分析了经典的短波高温修正模型的误差。针对黑体辐射源的不同溯源方法,讨论了辐射温度计校准中的发射率影响修正方法,并给出修正实例。所用方法可用于辐射测温应用、辐射温度计校准和黑体辐射源校准中的发射率和环境影响修正以及辐射源发射率不确定度对校准结果不确定度贡献的计算。 相似文献
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Accurate determination of temperature is one of the prime requirements in almost all the areas of physical metrology as it affects the process of any of the industrial manufacturing products. Planck’s equation serves the best approximation for determining temperature of a thermal radiating source. The ratio of pyrometric output signal due to intensities of two radiating sources can be utilized to measure temperature of an unknown source in terms of the temperature of reference metal freezing point source or a high stability tungsten strip lamp. The present paper provides an assessment of a set of tungsten lamps having strip or ribbon filament when compared against the emission of high stability standard lamps. The temperature measured in terms of electrical current across the lamp terminals has been estimated with an uncertainty reasonably acceptable for accurate determination of radiance temperature by these lamps. The uncertainty of temperature at each comparison point for lamps under assessment has been evaluated and reported. The best uncertainty of temperature was estimated to be ±1.7 K at 1073 K, ±1.5 K at 1273 K and ±3.7 K at 2473 K. The uncertainty at 1,073 K is higher as compared to at 1,273 K, is because of very low value of photocurrent signal produced due to low intensity observed at this temperature. The industrial strip lamps, compared against reference standard lamps serve as accurate sources of radiance temperature for comparing the disappearing filament Opto-spectral pyrometers used as direct temperature measuring instruments in the laboratories and in industries in the range above 1,073 K to as high as 2,500 K. 相似文献
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对SPCC冷轧钢带进行不同温度的热处理,热处理温度为550、600、650、700、750℃,保温时间5 min,然后快速水冷。研究不同热处理温度对SPCC冷轧钢带组织及力学性能的影响。结果表明,随着热处理温度的升高,SPCC冷轧钢带的屈服强度及抗拉强度升高,延伸率则降低,洛氏硬度增大。经550、600℃热处理后的SPCC冷轧钢带的金相组织为铁素体+球粒状珠光体,经750℃热处理后的金相组织则为铁素体+岛状珠光体。 相似文献
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黑体辐射源的多波长有效亮度温度校准和不同溯源方式特点分析 总被引:1,自引:0,他引:1
介绍了中国计量科学研究院建立的标准变温黑体辐射源和有效亮度温度比较装置;阐述了黑体辐射源多波长有效亮度温度校准的2种方法,给出典型校准结果并分析了辐射源特性。比较分析了3种溯源方式的性能特点及其应用的影响因素。提出控温复现性的概念,它是以往未被重视的辐射源关键性能参数。多波长有效亮度温度校准是可减小或消除有效发射率和接触测温测点温差影响的溯源方案,与传统溯源方式特性互补,可用于评价辐射源的有效发射率和测点温差,对控温复现性好的辐射源效果最优。 相似文献
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Xiaogang Sun Peng Xiao Guibin Yuan Jingmin Dai 《International Journal of Thermophysics》2009,30(1):249-256
The temperatures and emissivities of the metallic thermal protection blanket at (900–1,300) °C are investigated experimentally
by using a multi-wavelength pyrometer. A linear relation between the emissivity and true temperature at different wavelengths
is assumed. Based on this assumption, the true temperatures and spectral emissivities of the metallic thermal protection blanket
at the two temperature measurement points can be calculated simultaneously. Some experimental results for the practical data
processing of measurements performed on the metallic thermal protection blanket show that the difference between the calculated
temperature and the temperature measured by a standard thermocouple is within ± 10°C. 相似文献
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采用双温双压法原理研制了一套宽温度范围、测试室压力可变的标准湿度发生器。它能够测量发生温度范围为-50~90 ℃、相对压力范围为-50~0 kPa、扩展不确定度为0.3%RH~0.8%RH(k=2)的5%RH~96%RH全量程相对湿度。其测试室尺寸为150 mm×400 mm,样气流量为5~30 L/Min。通过设计高精度饱和器压力和流量自动调节装置,采用工控机与PLC相结合的操作控制方式,实现了全自动运行。冷镜式精密露点仪和重量法湿度计的实际测试结果均验证了其不确定度。 相似文献
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K. Boboridis A. Seifter A. W. Obst D. Basak 《International Journal of Thermophysics》2007,28(2):683-696
The radiance temperature of nickel at its melting point was measured at four wavelengths (in the nominal range of 1.5 to 5 μm)
by a pulse-heating technique using a high-speed fiber-coupled four-channel infrared pyrometer. The method was based on rapid
resistive self-heating of a specimen from room temperature to its melting point in less than 1 s while simultaneously measuring
the radiance emitted by it in four spectral bands as a function of time. A plateau in the recorded radiance-versus-time traces
indicated melting of the specimen. The melting-point radiance temperature for a given specimen was determined by averaging
the temperature measured along the plateau at each wavelength. The results for several specimens were then, in turn, averaged
to yield the melting-point radiance temperature of nickel, as follows: 1316 K at 1.77 μm, 1211 K at 2.26 μm, 995 K at 3.48 μm,
and 845 K at 4.75 μm. The melting-point normal spectral emittance of nickel at these wavelengths was derived from the measured
radiance in each spectral band using the published value of the thermodynamic (true) melting temperature of nickel. 相似文献
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衬底温度对碳纳米管生长和结构的影响 总被引:2,自引:0,他引:2
用CH4、NH3和H2为反应气体,利用等离子体增强热丝化学气相沉积在沉积有Ta缓冲层和Ni催化剂层的Si衬底上制备了准直碳纳米管,并用扫描电子显微镜和透射电子显微镜研究了它们的生长和结构随温度的变化.结果表明生长的准直碳纳米管是竹节型结构,其直径随衬底温度的降低而减小,生长速率随衬底温度的升高有一极值.从催化剂在衬底温度作用下的变化开始,分析了衬底温度对碳纳米管生长和结构的影响. 相似文献
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耐低温氟醚橡胶结构和基本物理性能研究 总被引:2,自引:0,他引:2
研究了耐低温氟醚橡胶的结构特征和基本物性,结果表明;^19F核磁共振谱中20-30×10^-6处化学位移是醚键的特征,-8×10^-6和-2×10^-6是-CN基团的指纹峰;V GLT和СКХ-260МПАН耐高温老化性能不低于F246氟橡胶,但低温性能能远优于F246,二者均可满足-50℃低温使用要求而且СКХ-260МПАН可以在更低温度下保持柔顺性。 相似文献