期刊
EXPERIMENTAL THERMAL AND FLUID SCIENCE
卷 68, 期 -, 页码 644-651出版社
ELSEVIER SCIENCE INC
DOI: 10.1016/j.expthermflusci.2015.07.001
关键词
Hydrodynamics; Tortuous microchannels; Micro-PIV; Visualisation; Transient behaviour; Fluctuations
资金
- University of Sydney International Scholarship (USydIS) programme
- Australian Research Council [DP120103235]
An experimental investigation is carried out to understand the hydrodynamics of single-phase water flow in a zigzag microchannel with a semi-circular cross-section (diameter 2 mm). The present study covers Reynolds numbers in the laminar regime, under both steady and transient conditions. Time-resolved velocity measurements were made using high-speed micro-Ply techniques. The influence of inlet unsteadiness on flow characteristics is investigated. Through time-resolved velocity measurements, a transition from a steady flow to a time-dependent oscillatory flow having a few dominant frequencies and subsequently to a complex transient flow is observed in the wavy channel. However, the transition to a transient flow occurs at much lower Reynolds numbers (Re-c similar to 215) than predicted numerically. The early transition is believed to be triggered by small inlet flow disturbances in the experiments, since the flow is very sensitive to the inlet conditions at sufficiently high Reynolds numbers. This hypothesis is supported by results from transient CFD simulations with fluctuating inlet boundary conditions. (C) 2015 Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据