CTAC/NaSal和PEO复合水溶液减阻和流变实验研究

Experimental study on drag reduction and rheology of CTAC/NaSal and PEO composite aqueous solution

深入研究表面活性剂和高分子聚合物复合水溶液减阻规律和流变特性,有助于理解复合减阻机理促进其在工程领域的应用。利用旋转圆盘减阻装置研究了温度、浓度和雷诺数对表面活性剂(CTAC/NaSal)、高分子聚合物(PEO)及其复合水溶液减阻率的影响;同时利用旋转流变仪研究了浓度、温度和剪切速率对三种减阻溶液表观黏度的影响。研究表明,PEO和CTAC/NaSal复合溶液的减阻率明显高于纯水溶液的减阻率,复合溶液具有减阻雷诺数和减阻温度范围宽及减阻率高的特点,且PEO浓度变化对复合溶液减阻率的影响小于CTAC/NaSal浓度变化的影响;在所测温度和雷诺数范围内,相同剪切速率下复合溶液的表观黏度基本高于纯溶液的,一些浓度组合的复合溶液在较低剪切速率和较高剪切速率下均出现剪切增稠现象,温度升高使复合溶液剪切增稠现象推迟、次数减小以及表观黏度峰值降低。

It is beneficial for understandings of drag-reducing mechanism and extendingits application to engineering fields to deeply investigate the drag-reducing law and rheological property of surfactant and polymer composite aqueous solution.The effects of temperature,concentration and Reynolds number on the drag-reducing rate and the apparent viscosity of surfactant(CTAC/NaSal),polymer(PEO)and their composite aqueous solutions are respectively studied with a rotating disk apparatus and a rheometer.Present investigations show that the drag-reducing rate of PEO and CTAC/NaSal composite solutions is significantly higher than that of pure aqueous solution of PEO or CTAC/NaSal.The composite solution shows the advantages of the wide range of Reynolds number and temperature of drag reduction and the high drag-reducing rate.The effect of PEO concentration on the drag-reducing rate of the composite solution is less than that of CTAC/NaSal concentration.Within the ranges of measurement temperature and Reynolds number,the apparent viscosity of the composite solution is basically higher than that of the pure solution at the same shear rate.Some composite solutions show shear-thickening at lower shear rate and higher shear rate respectively.The increase of temperature delays the shear-thickening phenomenon of composite solution,and reduces the times and the peak value of apparent viscosity of shear thickening.