中文摘要：

对连续循环光滑管道（直径分别为5,10,20 mm）中黄原胶水溶液流动的减阻特性进行了试验,分析了黄原胶减阻的浓度效应、管径效应以及抗剪切特性,得到了减阻率与黄原胶水溶液浓度的关系曲线、雷诺数（Re）与减阻率的影响曲线以及减阻率与剪切时间的变化曲线.结果表明：黄原胶是很好的减阻剂,在较低Re流动时黄原胶在相对较小直径（5,10 mm）管道中表现为B型减阻特性,而在较大管径（20 mm）中则为A型减阻;在高Re时黄原胶水溶液在3种管径管道流动中皆表现为B型减阻,由于其主要具有B型减阻特性,使得黄原胶具有较好的抗剪切特性.

英文摘要：

The systematic experiments on drag reduction characteristics of xanthan gum solution in conti- nuous cycle smooth pipes with diameters of 5, 10 and 20 mm were respectively conducted. The concen- tration and pipe diameter effects and the withstanding mechanical degradation of xanthan gum solution on drag reduction characteristics were analyzed to obtain relationship between drag reductions and concentra- tion of xanthan gum solution, influence of Reynolds number on drag reductions and percent drag reduc- tion changing with shearing time. The experimental results show that xanthan gum solution is good drag reduction agent. At low Reynolds number, xanthan gum solution performs type-B drag reduction characteristics in small pipes with diameter of 5 mm and 10 mm, but shows type-A drag reductions cha- racteristics in large pipe with diameter of 20 mm. At high Reynolds number, the xanthan gum solution performs type-B drag reduction characteristics in all pipe flows with three diameters. Xanthan gum solu- tion exhibits high resistance to mechanical degradation because of the essential type-B drag reduction cha- racteristics.