基于LabVIEW的拉脱法测量液体表面张力系数  

Measuring surface tension coefficient with LabVIEW-based pull-off method

作　　者：何羽新 陈政延 冯欢 褚红燕 HE Yuxin;CHEN Zhengyan;FENG Huan;CHU Hongyan(School of Physical Science and Technology,Nanjing Normal University,Nanjing 210046,China)

机构地区：[1]南京师范大学物理科学与技术学院,江苏南京210046

出　　处：《物理实验》2025年第3期18-24,共7页Physics Experimentation

摘　　要：液体表面张力系数是描述液体物理性质的重要参量.在拉脱法测量液体表面张力系数的实验中,拉伸液膜由于质量过小往往被忽略不计,从而增加测量误差,且拉力值点的读取也存在争议.针对上述问题,改进实验装置,使用测高仪测量易被忽略的拉伸液膜的高度,计算拉伸液膜的质量;引入LabVIEW上位机程序实时读取传感器拉力值,准确读取拉力最大值点.实验结果表明:改进后的实验装置可将液体表面张力系数的实验误差控制在1%,有效提高了拉脱法测量的实验精度.Surface tension coefficient is an important parameter to describe the physical properties of liquids.In the widely used pull-off method experiment measuring the surface tension coefficient,the tensile film is often neglected due to its small mass,which increases the measurement error,and the reading of the tensile value point is still controversial.Our experiment implemented two improvements to overcome the above problems.Firstly,the height of the tensile liquid film,which had been easy to be ignored,was measured by an altimeter and then the mass of the film could be calculated,thereby adhering strictly to the theoretical formula of the pull-off method.Secondly,the LabVIEW program was introduced to read the tension value of the sensor in real time,so as to facilitate the accurate reading of the point of the maximum value of the tensile force.The results showed that the experimental error of the surface tension coefficient could be controlled at about 1%,which effectively improved the experimental accuracy of the pull-off method.

关 键 词：拉脱法 液体表面张力系数 LABVIEW 

分 类 号：O552.421[理学—热学与物质分子运动论]