Abstract
A particle image velocimetry (PIV) technique has been used to analyze the flow characteristics behind a road vehicle with/without an air spoiler attached on its trunk and also to estimate its effect on the wake. A vehicle model scaled in the ratio of 1/43 is set up in the mid-section of a closed-loop water tunnel. The Reynolds number based on the vehicle length is 105. To investigate the three-dimensional structure of the recirculation zone and vortices, measurements are carried out on the planes both parallel and perpendicular to the free stream, respectively. The results show significantly different vorticity distributions in the recirculation region according to the existence of the air spoiler. The focus and the saddle point, appearing in the wake, are disposed differently along the spanwise direction. Regarding the streamwise vortices, the air spoiler produces large wing tip vortices. They have opposite rotational directions to C-pillar vortices which are commonly observed in the case that an air spoiler is absent. The wing tip vortices generate the down force and as a result, they might make the vehicle more stable in driving.
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Jin Seok Kim: He obtained his bachelor of Engineering in Mechanical Engineering from Sunchon National University, Korea in 2005 and is currently a master student in the above university.
Sungcho Kim: He received his master and Ph.D. degrees in Aeronautical Engineering in 1985 and 1989, respectively from KAIST, Korea, and worked in Central Technology Institute of Daewoo Heavy Industry Ltd. He researched in Mississippi State University and University of California, Santa Barbara as a visiting scholar in 1994 and 2000, respectively. And he served as the dean in College of Engineering, Sunchon National University, and has been working in School of Mechanical and Aerospace Engineering in Sunchon National University as a professor since 1989. His research area is experimental and computational fluid engineering.
Jaeyong Sung: He received his master and Ph.D. degrees in Mechanical Engineering in 1996 and 2001, respectively from Seoul National University, Korea, and worked for Digital Appliance Laboratory of LG Electronics Inc. as a senior researcher. Also he taught in Mechanical and Automotive Engineering of Sunchon National University as a professor. And he has been working in Department of Mechanical Engineering in Seoul National University of Technology as a professor since 2004. His research interests are all the areas related to PIV technology, hemodynamics, biochips, rarefied gas flow with DSMC, etc.
Jeong Soo Kim: He received his master and Ph.D. degrees in Aeronautical Engineering in 1987 and 1992, respectively from KAIST, Korea, and worked for KIMM, ADD, and KARI as a principal researcher. Also he researched in TRW(USA) as an assistant program manager from 1986 to 1998. And he has been a faculty member in School of Mechanical and Aerospace Engineering in Sunchon National University since 2004. His research interests are satellite propulsion system, measurement and visualization of injector spray pattern using PDA, combustion, test and evaluation of liquid rocket engine, etc.
Jongwook Choi: He received his master and Ph.D. degrees in Mechanical Engineering in 1995 and 1999, respectively from Chonnam National University, Korea, and worked for POSCO Technical Research Laboratories as a Post-doctoral researcher. Also he taught in Mechanical and Aerospace Engineering of Sunchon National University as a contract professor for four years. And he has been working in School of Mechanical and Aerospace Engineering in Sunchon National University as a professor since 2005. His research interests are heat transfer, computational fluid dynamics, etc.
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Kim, J.S., Kim, S., Sung, J. et al. Effects of an air spoiler on the wake of a road vehicle by PIV measurements. J Vis 9, 411–418 (2006). https://doi.org/10.1007/BF03181780
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DOI: https://doi.org/10.1007/BF03181780