多通道数据采集系统测试导热系数的研究  

Study on Thermal Conductivity Using Multimeter/Data Acquisition System

作　　者：赵惠忠[1] 张敏[2] 张杰[3] 刘震炎[4] 

机构地区：[1]上海理工大学城市建设与环境工程学院,上海200093 [2]上海水产大学食品学院制冷与空调系,上海200090 [3]河南省气象局,河南郑州450000 [4]上海交通大学机械与动力工程学院,上海200240

出　　处：《仪表技术与传感器》2008年第10期103-105,共3页Instrument Technique and Sensor

基　　金：国家自然科学基金资助项目(30771245);上海市第5期教委重点学科建设项目(J50502)

摘　　要：基于线热源瞬态模型,根据铜电阻与温度之间相关关系的特性,对微热探针内部的细小铜漆包线加以恒定的加热电压,通过多通道数据采集系统对惠斯登电桥平衡电压进行测试,从而得到了微热探针内部、探针、待测样品的温度变化,进而得出被测样品的导热系数。该测试方法具有线性相关度高>0.999 9,标定偏差小的特点,最大偏差仅为2.5%,采用该测试方法测试液体以及松散材料导热系数,测试的最大误差<3.5%。该测试方法具有测量时间短,通常<20 s;试样温升<2℃,对被测样品的影响较小的特点。Based on the linear thermal resource model, the thermal conductivity of experimental sample was determined. The balance voltage of Wheatstone bridge was measured when a constant copper temperature varied with resistance variance. The thermal conductivities were determined by the variance of the tiny probe inner temperature, the tiny temperature and the experimental sample temperature. The following conclusion could be drawn, the linear correlation of this method is higher than 0.9999 and the measurement err is less than 2.5%. Using this experimental set to determine thermal conductivities of some samples, the max err of measurement is less than 3.5%. The experiment sample were got less affect for test,and the test time were less than 20 s and the temperature risen is less than 2℃.

关 键 词：导热系数 微热探针 数据采集系统 惠斯登电桥 

分 类 号：TH81[机械工程—仪器科学与技术] TK31[机械工程—精密仪器及机械]