The velocity and friction properties of laminar pipe flow of a viscoelastic solution are bounded by the corresponding values for two Newtonian fluids, namely, the solvent and a fluid with a viscosity identical to the total viscosity of the solution. The lower friction factor for the flow of the solution when compared to the latter is tracked to an increased strain rate needed to enhance viscous dissipation. Finally, we show analytically that the effective viscosity varies similarly to the radial diagonal component of the conformation tensor as observed numerically in turbulent flows and give a lucid interpretation of shear-thinning through a sequence of underlying constitutive physical phenomena.

中文翻译：

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管流中的粘弹性层流阻力边界

粘弹性溶液层流管流的速度和摩擦特性受两种牛顿流体的相应值的限制，即溶剂和粘度等于溶液总粘度的流体。与后者相比，溶液流动的较低摩擦系数被追踪到增加的应变率以增强粘性耗散。最后，我们通过分析表明，有效粘度的变化类似于在湍流中以数值方式观察到的构象张量的径向对角分量，并通过一系列潜在的本构物理现象对剪切稀化进行了清晰的解释。