文献类型：期刊文献

英文题名：Polymer effects on viscoelastic fluid flows in a planar constriction microchannel

作者：Wu, Sen[1,2];Raihan, Mahmud Kamal[2];Song, Le[2,3];Shao, Xingchen[4];Bostwick, Joshua B.[2];Yu, Liandong[3,5];Pan, Xinxiang[1,6];Xuan, Xiangchun[2]

机构：[1]Dalian Maritime Univ, Coll Marine Engn, Dalian 116026, Peoples R China;[2]Clemson Univ, Dept Mech Engn, Clemson, SC 29634 USA;[3]Hefei Univ Technol, Sch Instrument Sci & Optoelect Engn, Hefei 230009, Peoples R China;[4]Johns Hopkins Univ, Dept Chem & Biomol Engn, Baltimore, MD 21218 USA;[5]China Univ Petr, Coll Controlling Sci & Engn, Qingdao 257061, Peoples R China;[6]Guangdong Ocean Univ, Maritime Coll, Zhanjiang 524088, Peoples R China

年份：2021

卷号：290

外文期刊名：JOURNAL OF NON-NEWTONIAN FLUID MECHANICS

收录：SCI-EXPANDED(收录号：WOS:000639273400003)、、EI(收录号：20210909996871)、Scopus(收录号：2-s2.0-85101522666)、WOS

基金：This work was supported in part by China Scholarship Council (CSC) -Chinese Government Graduate Student Overseas Study Program (S.W. and L.S.), University 111 Project of China under grant number B12019 (L.Y.), Clemson University through a SEED grant (X.X.), and NSF under grant number CBET-1750208 (J.B.B.).

语种：英文

外文关键词：Polymer solutions; Elasticity; Shear thinning; Inertia; Microfluidic model; Porous media

外文摘要：A comprehensive understanding of the flow of viscoelastic polymer solutions in a contraction and/or an expansion geometry concerns numerous applications. The effects of polymer type, molecular weight, and concentration are investigated through controlled experiments with polyethylene oxide (PEO), polyvinylpyrrolidone (PVP) and hyaluronic acid (HA) solutions in a planar constriction microchannel in a wide range of Reynolds (Re) and Weissenberg (Wi) numbers. The polymer structure renders drastic differences amongst the contraction flows of 3000 ppm PEO, PVP, and HA solutions despite having similar molecular weights. The expansion flow vortices of these solutions remain analogous to those in the inertial flow of water. Increasing the molecular weight or concentration of PEO polymer promotes the elastic instabilities in both the contraction and expansion flows. It, however, suppresses (and even blocks) the inertial vortices in the expansion flow and makes them start from the salient corners, in contrast to the lips of the expansion walls in water. Interestingly, a sudden decrease in the size of inertial vortices is observed in the expansion flow of 500 ppm, 1 megadalton PEO solution when the elastic disturbances start appearing in the contraction flow. The observed flow regimes and vortex development in the polymer solutions are summarized in the same dimensionless Re - Wi and Re - chi(L) parameter spaces, where chi(L) is the normalized vortex length. The elasticity number, El = Wi/Re, is found to determine and distinguish the contraction and expansion flows.