A novel microfluidic device for efficient passive mixing is reported. A series of sharp corner structures designed on side wall of an arc microchannel was utilized to induce three-dimensional vortices, which strongly stretched and folded the interface and significantly increased the interfacial contact area between different fluids. Additionally, the sharp corner structure induced high radial velocity and reduced the diffusion length because of the restricted effect of the geometrical structure. Eventually, the fluid mixing was significantly enhanced, and a mixing efficiency from ∼87% to 92% was achieved at moderate Reynolds number (Re) from 3.0 to 24.2 (10 to 80 μl min⁻¹). The influence of the sharp corner position on the mixing was also investigated by the experiment and the numerical simulation. With single-layer structure and high mixing efficiency, the present device has great potential in the mixing process in variety of lab-chip applications, such as clinic diagnosis and analytic chemistry.

报道了一种用于有效被动混合的新型微流体装置。弧形微通道侧壁上设计的一系列尖角结构用于诱导三维涡流，强烈拉伸和折叠界面，显着增加不同流体之间的界面接触面积。此外，由于几何结构的限制作用，尖角结构引起了高径向速度并减少了扩散长度。最终，流体混合显着增强，在中等雷诺数 ( Re ) 从 3.0 到 24.2（10 到 80 μ l min ^-1）。还通过实验和数值模拟研究了尖角位置对混合的影响。该装置具有单层结构和高混合效率，在各种实验室芯片应用的混合过程中具有巨大的潜力，例如临床诊断和分析化学。