It is well known that drag reduction properties of polymer solutions in pipe flows are classified into two categories, based on the relationship between the friction factor and the Reynolds number. The degree of drag reduction either increases with an increase in the Reynolds number or is independent of the Reynolds number. In the latter case, the drag reduction behavior is referred to as type B behavior. In this study, the pressure losses of aqueous suspensions of biofibers and graphene oxide flat particles in pipe flows were measured to clarify the effect of the shape of suspended fine solid matter on the friction factor. The experimental results demonstrated that the behavior of the friction factor corresponded with the type B behavior of drag reduction. The mean velocity profile in the range of the turbulent flow was also estimated from the friction factor data.

中文翻译：

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减少管道中精细固体物质的水悬浮液的阻力

众所周知，基于摩擦系数和雷诺数之间的关系，管流中聚合物溶液的减阻特性可分为两类。阻力减小的程度或者随着雷诺数的增加而增加，或者与雷诺数无关。在后一种情况下，减阻行为称为B型行为。在这项研究中，测量了生物纤维和氧化石墨烯扁平颗粒在管道中的水悬浮液的压力损失，以阐明悬浮的细固体形状对摩擦系数的影响。实验结果表明，摩擦系数的行为与减阻的B型行为相对应。