用落球法变温粘滞系数实验仪测液体的粘滞系数误差分析

Error Analysis in Liquid Viscous Coefficient Measurement by Using Falling Ball Method Experimental Apparatus of Variable Temperature Coefficient of Viscosity

文章主要针对用落球法变温粘滞系数实验仪测量液体的粘滞系数实验进行了误差分析。总结了影响系统测量精度的主要误差来源于以下八个方面:油筒未放置水平;液体温度与水温不一致;液面产生漩涡;小球下落偏离轴线方向;小球刚进入液体时为非匀速运动;小球作匀速运动对油筒刻线位置判断不准确;秒表计时;小球表面污染等。

The article mainly discusses the error analysis in the liquid viscous coefficient measurement by using falling ball method experimental apparatus of variable temperature coefficient of viscosity, and makes a conclusion that the main error resources are come from the following eight aspects： oil cylinder not placed horizontally; liquid temperature and water temperature not consistent; liquid surface occurring vortex; the balls falling off axis direction; the speed of ball being not constant when falling in the liquid at the beginning; the judgement to the scribed line location of oil cylinder not accurate when the ball making uniform motion in oil cylinder; a stopwatch timing; ball surface contamination.