【摘要】 目的：微锥孔是介观尺度流体进行混合、反应与分离等作用的主要场所，其壁面质量对功能效果至关重要。本文旨在探讨压电超声耦合磨粒流的微锥孔抛光技术，研究超声作用下微锥孔流场特性与壁面冲蚀效果之间的定量关系，从而提升微锥孔壁面的加工质量。创新点：1.建立针对微锥孔内壁面材料去除的压电超声耦合磨粒流抛光模型，并提出一种基于压电超声多能场耦合的颗粒运动求解方法，进而得到压电超声振动下颗粒—壁面碰撞机理和冲蚀特性；2.研究了周期性振动下微锥孔流场压力变化规律和磨粒运动轨迹，并实现了抛光区域冲蚀效果的主动调控。方法：1.基于压电超声作用下锥孔的扩缩机制，结合DPM方法和改进的壁面处理技术，构建微锥孔脉动流场中的颗粒运动模型（公式(5)）;2.通过数值仿真，运用CFD-DPM方法及Finnie冲蚀模型分析微锥孔扩缩周期内流场的速度和压力分布以及颗粒运动轨迹（图7和8），并探讨振幅与频率对壁面冲蚀率和冲蚀位置的影响（图10和11）;3.通过搭建PU-AP抛光实验平台，定量监测微锥孔表面粗糙度，并综合对比不同抛光时间的抛光效果，验证所提方法的可行性和有效性（图13）。结论：1.计算得出了PU-AP过程中旋涡形成、磨粒运动和壁面冲蚀的全过程；2.磨粒的撞击频率和位置与微锥孔壁面抛光效果之间存在显著的映射关系，揭示了振动频率和幅值对微锥孔特定区域抛光效果的影响；3.不同抛光时间的对比实验表明，随着加工时间的增加，微锥孔壁面粗糙度显著降低，所以抛光效果得到明显改善。更多还原

【Abstract】 The primary determinant of microfluidic chip performance is the surface quality of the micro-tapered holes. Due to the small scale of these holes and the high hardness of the surface attachments, the commonly used abrasive jet polishing method can encounter difficulties. Therefore, we propose a novel active multiphase field material removal technique. This technique is based on piezoelectric ultrasonically coupled abrasive particle flow. To study the connection between the impulse properties of the flow field and the micro-tapered hole’s asymptotic expansion–contraction process, a multiphase hybrid fluid dynamics model is established. Simultaneously, we investigate the process of abrasive–wall contact during the cycles of expansion and contraction, revealing the effects of erosion and polishing on different areas of the hole surface. To achieve accurate regulation of a desired polishing area, a quantitative relationship between the vibrational properties of piezoelectric ceramics and the erosional effect of micro-tapered holes is established. Finally, an experimental platform for micro-tapered hole polishing is built to validate the method.更多还原