caa a22 4500 463234871 CHVBK 20180405153253.0 cr unu---uuuuu 170326e20070201xx s 000 0 eng 10.1007/s10404-006-0099-2 doi (NATIONALLICENCE)springer-10.1007/s10404-006-0099-2 Capabilities and limitations of 2-dimensional and 3-dimensional numerical methods in modeling the fluid flow in sudden expansion microchannels [Elektronische Daten] [Chien-Hsiung Tsai, Han-Taw Chen, Yao-Nan Wang, Che-Hsin Lin, Lung-Ming Fu] This paper deals with computational and experimental investigations into pressure-driven flow in sudden expansion microfluidic channels. Improving the design and operation of microfluidic systems requires that the capabilities and limitations of 2-dimensional (2-D) and 3-dimensional (3-D) numerical methods in simulating the flow field in a sudden expansion microchannel be well understood. The present 2-D simulation results indicate that a flow separation vortex forms in the corner behind the sudden expansion microchannel when the Reynolds number is very low (Re∼0.1). However, the experimental results indicate that this prediction is valid only in the case of a sudden expansion microchannel with a high aspect ratio (aspect ratio >>1). 3-D computational fluid dynamics simulations are performed to predict the critical value of Re at which the flow separation vortex phenomenon is induced in sudden expansion microchannels of different aspect ratios. The experimental flow visualization results are found to be in good agreement with the 3-D numerical predictions. The present results provide designers with a valuable guideline when choosing between 2-D or 3-D numerical simulations as a means of improving the design and operation of microfluidic devices. Springer-Verlag, 2006 Sudden expansion microchannel nationallicence Reynolds numbers nationallicence Flow separation vortex nationallicence Tsai Chien-Hsiung Department of Vehicle Engineering, National Pingtung University of Science and Technology, 912, Pingtung, Taiwan aut Chen Han-Taw Department of Mechanical Engineering, National Cheng-Kung University, 701, Tainan, Taiwan aut Wang Yao-Nan Department of Mechanical Engineering, National Cheng-Kung University, 701, Tainan, Taiwan aut Lin Che-Hsin Department of Mechanical and Electro-Mechanical Engineering, National Sun Yat-sen University, 804, Kaohsiung, Taiwan aut Fu Lung-Ming Graduate Institute of Materials Engineering, National Pingtung University of Science and Technology, 912, Pingtung, Taiwan aut Microfluidics and Nanofluidics Springer-Verlag 3/1(2007-02-01), 13-18 1613-4982 3:1<13 2007 3 10404 https://doi.org/10.1007/s10404-006-0099-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10404-006-0099-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tsai Chien-Hsiung Department of Vehicle Engineering, National Pingtung University of Science and Technology, 912, Pingtung, Taiwan aut NATIONALLICENCE 700 1- Chen Han-Taw Department of Mechanical Engineering, National Cheng-Kung University, 701, Tainan, Taiwan aut NATIONALLICENCE 700 1- Wang Yao-Nan Department of Mechanical Engineering, National Cheng-Kung University, 701, Tainan, Taiwan aut NATIONALLICENCE 700 1- Lin Che-Hsin Department of Mechanical and Electro-Mechanical Engineering, National Sun Yat-sen University, 804, Kaohsiung, Taiwan aut NATIONALLICENCE 700 1- Fu Lung-Ming Graduate Institute of Materials Engineering, National Pingtung University of Science and Technology, 912, Pingtung, Taiwan aut NATIONALLICENCE 773 0- Microfluidics and Nanofluidics Springer-Verlag 3/1(2007-02-01), 13-18 1613-4982 3:1<13 2007 3 10404 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer