本研究針對塑膠微粒設計一矩形橫截面之螺旋流道,透過流體的慣性聚焦使不同尺寸的粒子在螺旋型流道中分離。由於粒子在流道中的聚焦位置與其大小有關,本實驗也對慣性聚焦原理進行深入的探討與計算。此外,本流道設計在出口部分額外增加 PZT 壓電材料,利用聲波所產生的聲輻射力作用在粒子上,提高分離的效率及分離尺寸範圍。最後,本實驗以電容式量測對分離後的粒子溶液進行分析,發現溶液中粒子濃度越高,電容值的變化量越大。;This study designs a spiral flow channel with a rectangular cross-section for plastic particles. Particles are separated in the spiral flow channel through the inertial focusing of the fluid. Since the focusing position of the particles in the flow channel is related to its size, the principle of inertial focusing is also discussed and calculated in this experiment. In addition, at outlet part of the flow channel, we install piezoelectric material. Using the acoustic radiation force generated by the acoustic wave that acting on the particles to improve the separation efficiency and the separation size range. Finally, in this experiment, the separated particle solution was analyzed by capacitive measurement. It was found that the higher the particle concentration in the solution, the greater change in capacitance value.