黄原胶水溶液管道流动转捩及不同NaCl质量分数下减阻特性的实验研究  

Experimental study on pipe flow transition of XG solution and drag reduction characteristics with different mass fractions of NaCl

作　　者：徐晟轩 赵文斌[1] 李明义[1] 林玉莹 李昌烽[1] XU Shengxuan;ZHAO Wenbin;LI Mingyi;LIN Yuying;LI Changfeng(School of Energy and Power Engineering,Jiangsu University,Zhenjiang Jiangsu 212013,China)

机构地区：[1]江苏大学能源与动力工程学院,江苏镇江212013

出　　处：《实验流体力学》2021年第4期34-40,共7页Journal of Experiments in Fluid Mechanics

基　　金：国家自然科学基金(51576092);江苏高校优势学科建设资助项目。

摘　　要：在水平光滑圆管内,采用雷诺实验对质量分数为0~400×10^(-6)的黄原胶水溶液的流动转捩特性进行了观测,并通过实验探究了不同质量分数的盐(NaCl)环境对黄原胶溶液减阻特性的影响,测量了(100~300)×10^(-6)的黄原胶溶液在不同NaCl质量分数(0、250×10^(-6)、500×10^(-6)和1000×10^(-6))下的减阻率与流动雷诺数(Re)、剪切时间之间的关系。结果表明:以广义雷诺数表征时,黄原胶水溶液管道流动转捩的下临界雷诺数随质量分数的增加而上升,近似呈线性变化,而转捩的上临界雷诺数却迅速降低至3000左右;在高雷诺数下,随着NaCl质量分数的增加,黄原胶盐溶液的饱和减阻率显著降低,但在低雷诺数下的减阻效果优于水溶液;黄原胶水溶液的抗剪切性呈质量分数效应,适量盐的加入能略微提高其抗剪切性。The Reynolds experiment was conducted to study the transition characteristics of Xanthan Gum(XG)solution(mass fraction:(0-400)×10^(-6))in a horizontal smooth circular pipe flow.The influence of different mass fractions of the salt(NaCl)environment on the drag reduction characteristics of XG solution was also investigated experimentally.The relationships of the drag reduction efficiency of XG solution(mass fraction:(100-300)×10^(-6))with the flow Reynolds number(Re)and the shearing time in different NaCl mass fractions(0、250×10^(-6)、500×10^(-6)和1000×10^(-6))were measured.Characterized by the generalized Reynolds number,the flow transition lower critical Reynolds number is delayed in an approximately linear mode with the increase of XG mass fraction,while the value of the upper critical Reynolds number rapidly drops to about 3000.The saturated drag reduction efficiency of XG solution decreases significantly with the dissolution of NaCl under the high Reynolds number condition.Nevertheless,a better drag reduction effect appears under the low Reynolds number condition.The shearing resistance of XG solution shows mass fraction effect,while the addition of an appropriate amount of salt can slightly improve the shearing resistance.

关 键 词：黄原胶溶液 质量分数 转捩 减阻 抗剪切性 

分 类 号：O130.25[理学—数学]