Measurement of Turbulence and Heat Transfer Enhancement Structure of Polymer Solution Flows in Microchannel

为了评价非牛顿流体在蛇形通道中的强化传热性能，对粘弹性流体在蛇形通道中的流动进行了传热和压力损失的测量以及流动显示。采用聚丙烯酰胺水溶液作为粘弹性流体。流场显示结果表明，即使在雷诺数小于2的情况下，也会产生非定常流动和纵向涡状二次流。0的粘弹性流体的情况下。与牛顿流体相比，这些流动产生了显著的传热强化效果。此外，一个良好的相关性之间的传热和压力损失特性与Weissenberg数。

Heat transfer and pressure loss measurements and flow visualization were carried out for viscoelastic fluid flow in a serpentine channel in order to evaluate the heat transfer enhancement performance of using such non-Newtonian fluids. Polyacrylamide water solution was used as viscoelastic fluid. The visualized flow patterns showed that unsteady flows and longitudinal vortex-like secondary flows are generated even under the condition of$ Re<$ 2. 0 in the viscoelastic fluid case. These flows produced a remarkable heat transfer enhancement effect compared to the case of Newtonian fluid. Further, a good correlation was observed between the heat transfer and pressure loss characteristics with the Weissenberg number.