论文部分内容阅读
为了提高液体表面张力系数的测量精度,并充分发挥光纤干涉法的高精度、非接触等优点,提出了一种利用干涉原理的空心光纤(HOF)液体表面张力系数测量方法。即利用HOF一端与单模光纤(SMF)相连,另一端与待测液面接触形成Fabry-Perot(F-P)腔实现液体表面张力系数的测量。毛细效应使得被测液体进入HOF内,不同的表面张力导致HOF形成的F-P腔腔长发生变化,通过检测F-P腔两个相邻干涉峰的间距就可以间接得出液体的表面张力系数大小。实验中,分别测定了相同温度下5种不同液体的表面张力系数和不同温度下蒸馏水的表面张力系数,对测量的结果进行最小二乘法线性拟合。实验中,温度的改变采用水浴加热法,不同温度下蒸馏水表面张力系数的测量结果与理论值的最大误差为0.26%。本文方法结构简单,容易操作,有较高的灵敏度,可为实际液体表面张力系数测量提供参考。
In order to improve the measurement accuracy of the liquid surface tension coefficient and give full play to the advantages of high precision and non-contact of the fiber interference method, a method for measuring the surface tension coefficient of a hollow fiber (HOF) liquid using an interference principle is proposed. That is to say, the surface tension coefficient of the liquid is measured by using one end of the HOF connected to the SMF and the other end in contact with the liquid to be measured to form a Fabry-Perot (F-P) cavity. The capillary effect causes the measured liquid to enter the HOF. Different surface tension causes the length of the F-P cavity formed by the HOF to change. By measuring the distance between two adjacent interference peaks in the F-P cavity, the surface tension coefficient of the liquid can be obtained indirectly. In the experiment, the surface tension coefficients of five different liquids at the same temperature and the surface tension coefficients of distilled water at different temperatures were measured respectively, and the results of the measurements were fitted by the least squares linear fit. In the experiment, the temperature was changed by water bath heating method. The maximum error between theoretical value and measured result of surface tension coefficient of distilled water at different temperature was 0.26%. The proposed method is simple in structure, easy to operate and has high sensitivity. It can provide a reference for the measurement of surface tension coefficient of real liquid.