不同温度下液体粘滞系数实验的理论计算

Theoretical Computation for Experiment of Viscosity Coefficient of Liquid under Different Temperature

落球法测液体粘滞系数是理工科高校的一个基本物理实验。环境温度对液体的密度和粘度有很大影响,所以温度在该实验中是一个重要的参数。该文从理论上对不同温度下不同直径的小球在测量区间内匀速下落的时间、收尾速度和匀速下落起点位置进行了计算,并给出了这些参量随着温度变化的规律。实践表明,这为实验者选择合适的实验参数、判断实验数据准确性提供了依据,从而减少了误差。

Falling ball method,which measures the viscosity coefficient of liquid,is a basic physical experiment of science and engineering university. Environmental temperature has a significant effect on the fluid density and viscosity. Thus,the temperature is an important parameter in this experiment. In this paper,the falling time in the measuring interval,the terminal falling velocity and the starting position of uniform falling are theoretically calculated under different temperatures and diameters which were given. The results show the law of these parameters varied with the temperature. It provides the basis for the experimenter to select the appropriate experimental parameters,which can reduce the error.