Flow rectification for Newtonian fluids remains challenging compared with that for non-Newtonian fluids because the physical properties of Newtonian fluids are independent of the structure of flow channels, and flow rectification can only be achieved through direction-dependent flow scenarios. In this work, we fabricate a microfluidic rectifier for Newtonian fluids using asymmetric converging–diverging microchannels. The highest diodicity measured for the rectifier is 1.77, which is 15%–54% higher than previous microfluidic rectifiers for Newtonian fluids. An expression for the diodicity is developed based on two scaling laws for the flow resistances in the forward and backward directions. Numerical simulations are also performed to confirm the experiments.

中文翻译：

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使用不对称会聚-发散微通道的牛顿流体微流控整流器

与非牛顿流体相比，牛顿流体的流动整流仍然具有挑战性，因为牛顿流体的物理性质与流道结构无关，并且流动整流只能通过依赖于方向的流动场景来实现。在这项工作中，我们使用不对称的会聚-发散微通道为牛顿流体制造了微流控整流器。整流器测得的最高二元性为 1.77，比之前用于牛顿流体的微流控整流器高 15%–54%。二元性的表达式是基于向前和向后流动阻力的两个标度定律开发的。还进行了数值模拟以确认实验。