利用数字散斑相关法测量热膨胀系数

Approach of digital speckle correlation to measure thermal expansion coeffcient

提出用数字散斑照相技术结合PC机软件对热膨胀系数进行测量的方案,并通过实验验证了该方案的可行性.通过用最科学、最合理的最小二乘法处理数据拟合最佳温度-位移曲线,由实验数据计算出来的铜管热膨胀系数与公认值相比只有1.2%误差.相对于传统的测量方法,本方案提高了测量的精度并简化了测量过程.由其高精确度我们可以运用激光数字散斑方法测量热膨胀系数公认值表中没有的物质的热膨胀系数.

The digital speckle photographic technology combining with PC software for measuring thermal expansion coefficient is proposed. The project is feasible verified by experiments. By using the most scientific and reasonable method of least squares to process data,the optimal temperature- displacement curve is obtained. The experimental results compared with the Cu thermal expansion coefficient of recognized has 1. 2% error. In comparison with the traditional measurement methods,this approach improves accuracy and simplifies procedure. So it can be used to measure unknown thermal expansion coefficient.