毛细管两端不同压强差对稀溶液粘度测量的影响

The Effect of Different Pressure Differences between Capillary Tubes on Viscosity Measurement of Dilute Solution

针对当前稀溶液流经毛细管使溶液中分子吸附在管壁上,导致稀溶液粘度测量准确度不高,从而影响毛细管两端不同压强差对稀溶液粘度测量影响分析准确性,提出一种基于哈根-泊肃叶定律的毛细管两端不同压强差对稀溶液粘度测量的影响分析方法,以毛细管粘度计非计时刻度线区的液位检测信息为先验知识,利用罗曼诺夫斯基准则,确定毛细管粘度计非计时刻度线区向计时刻度线区过渡的特征点,并利用模糊判决调整液位检测电压的采样时间间隔,并以此特征点作为拟合起点,对采集到的数据进行预处理,保证分析的准确性。在此基础上,利用哈根-泊肃叶定律,根据稀溶液流过时间测定之前和之后纯溶剂在乌氏粘度计中流过的时间,证明稀溶液粘度测量过程中,分子会吸附在毛细管的管壁上,吸附层厚度与分子量无关,从而对稀溶液粘度进行计算,实验结果表明,所提方法能够准确对稀溶液粘度进行测量,测量的精确度较高,能够准确分析出毛细管两端不同压强差与稀溶液粘度之间关系。

Aiming at the problem that the current dilute solution flows through the capillary to adsorb the molecules in the solution on the wall of the tube,the measurement accuracy of the dilute solution viscosity is not high,which affects the accuracy of the differential pressure difference measurement on the dilute solution at both ends of the capillary. Hagen-Poiseuille law capillary pressure at both ends of the different methods of dilute solution viscosity measurement method to capillary viscometer non-timing line area of the liquid level detection information as a priori knowledge,the use of Romanovsky criteria,Determine the non-time tick line area to the timing mark line over the feature points,and the use of fuzzy decision to adjust the liquid level detection voltage sampling interval,and take this feature point as a fitting starting point,the collected data pretreatment,Ensure the accuracy of the analysis. On this basis,using the Hagen-Poiseuille law,the time for the pure solvent to flow in the Ubbelohde viscometer before and after the dilute solution flow-through time is determined,and it is proved that the molecules adsorb to the capillary during the viscosity measurement of the dilute solution The thickness of the adsorption layer has nothing to do with the molecular weight,so the viscosity of dilute solution is calculated. The experimental results show that the proposed method can accurately measure the viscosity of dilute solutionwith high accuracy and can accurately analyze the difference between the two ends Relationship between pressure difference and viscosity of dilute solution.