A Versatile Flow-Profile Engineering Method in the Stokes Flow Regime for Complex-Shaped Flows

• 作者: Zhenyu Yang Lang Nan Ho Cheung Shum
• 来源期刊: 工程（英文）
• 年，卷（期）: 2021,（5）
• 所属期刊栏目: Green Chemical Engineering:Soft Matter—Article
• 页码范围: 655-662
• 页数: 8页
• 语种: 英文

摘要

Flow profiles are frequently engineered in microfluidic channels for enhanced mixing,reaction control,and material synthesis.Conventionally,flow profiles are engineered by inducing inertial secondary flow to redistribute the streams,which can hardly be reproduced in microfluidic environments with negligible inertial flow.The employed symmetric channel structures also limit the variety of achievable flow pro-files.Moreover,each of the flow profiles specifically corresponds to a strictly defined flow condition and cannot be generalized to other flow environments.To address these issues,we present a systematic method to engineer the flow profile using inertialess secondary flow.The flow is manipulated in the Stokes regime by deploying a cascaded series of microsteps with various morphologies inside a microchannel to shape the flow profile.By tuning the shapes of the microsteps,arbitrary outflow profiles can be customized.A numerical profile-transformation program is developed for rapid prediction of the output profiles of arbitrary sequences of predefined microsteps.The proposed method allows the engi-neering of stable flow profiles,including asymmetric ones,over a wide range of flow conditions for com-plex microfluidic environmental prediction and design.