光纤传感器测量固体材料线胀系数实验的改进

摘要

The experiment of measuring the linear expansion coefficient of solid material by using reflective optical fiber sensor was improved .To enhance the sensitivity of the fiber optical sensor ,the method of multi fiber coaxial emission/receiving was adopted .To increase the accuracy of temperature measurement ,the low‐voltage silicon heating sheet was used instead of the traditional heating meth‐ods .The linear range of the sensor output was directly compared with the linear variation of the ther‐mal expansion of the material .The improved experimental apparatus was simple and easy to operate , the measuring length of the sample was 200 mm ,and the measured linear expansion coefficient of plexiglass and brass were 131 .4 × 10-6/℃ and 18 .35 × 10-6/℃ ,the error of the experimental results was about 1% .%对反射式光纤传感器测量固体材料线胀系数实验进行了改进．光纤探头采用多光纤同轴发射／接收，提高了光纤传感器的灵敏度，低压硅胶板的加热方式改变了传统的加热方式，提高了温度测量的准确度，同时还改进了材料的加热方式，并将传感器输出特性的线性区间与材料热膨胀时的线性变化直接对比进行数据处理．改进后的实验装置简单且便于操作，可测量长度为200 m m的样品，测得有机玻璃和黄铜的线膨胀系数分别为131．4×10－6／℃和18．35×10－6／℃，实验结果的相对偏差约为1％．