Characteristics of low-speed streaks and vortex structures in drag-reduced turbulent channel flow investigated by stereoscopic PIV

Feng Chen Li, Takehiko Segawa, Yasuo Kawaguchi, Koichi Hishida

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

In the present study, we employed stereoscopic particle image velocimetry (SPIV) to investigate the characteristics of turbulence structures in a drag-reduced turbulent channel flow with addition of surfactant. The tested drag-reducing fluid was a CTAC (cetyltrimethyl ammonium chloride)/NaSal/Water system maintained at 25°C, having a 30-ppm concentration of CTAC. SPIV measurement was performed for a water flow (Re = 1.1×105) and a CTAC solution flow (Re = 1.5×105 with 54% drag reduction) in both the streamwise-spanwise and wall-normal-spanwise planes, respectively. A series of wall-normal vortex cores were found to align with the low-speed streaks with opposite vorticity signals at both sides of the streaks and with the vorticity decreased averagely by about one order in CTAC solution flow compared with water flow; the spanwise spacing between the low-speed streaks in the solution flow is increased by about 42%. The streamwise vorticity of the vortex cores appearing in the wall-normal-spanwise plane was also decreased by the use of additives.

Original languageEnglish
Title of host publicationAmerican Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED
Pages855-862
Number of pages8
Volume260
DOIs
Publication statusPublished - 2004
Event2004 ASME International Mechanical Engineering Congress and Exposition, IMECE 2004 - Anaheim, CA, United States
Duration: 2004 Nov 132004 Nov 19

Other

Other2004 ASME International Mechanical Engineering Congress and Exposition, IMECE 2004
CountryUnited States
CityAnaheim, CA
Period04/11/1304/11/19

Fingerprint

Channel flow
Vorticity
Drag
Vortex flow
Velocity measurement
Water
Drag reduction
Turbulence
Surface active agents
Fluids

ASJC Scopus subject areas

  • Engineering(all)

Cite this

Li, F. C., Segawa, T., Kawaguchi, Y., & Hishida, K. (2004). Characteristics of low-speed streaks and vortex structures in drag-reduced turbulent channel flow investigated by stereoscopic PIV. In American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED (Vol. 260, pp. 855-862). [IMECE2004-61023] https://doi.org/10.1115/IMECE2004-61023

Characteristics of low-speed streaks and vortex structures in drag-reduced turbulent channel flow investigated by stereoscopic PIV. / Li, Feng Chen; Segawa, Takehiko; Kawaguchi, Yasuo; Hishida, Koichi.

American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED. Vol. 260 2004. p. 855-862 IMECE2004-61023.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Li, FC, Segawa, T, Kawaguchi, Y & Hishida, K 2004, Characteristics of low-speed streaks and vortex structures in drag-reduced turbulent channel flow investigated by stereoscopic PIV. in American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED. vol. 260, IMECE2004-61023, pp. 855-862, 2004 ASME International Mechanical Engineering Congress and Exposition, IMECE 2004, Anaheim, CA, United States, 04/11/13. https://doi.org/10.1115/IMECE2004-61023
Li FC, Segawa T, Kawaguchi Y, Hishida K. Characteristics of low-speed streaks and vortex structures in drag-reduced turbulent channel flow investigated by stereoscopic PIV. In American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED. Vol. 260. 2004. p. 855-862. IMECE2004-61023 https://doi.org/10.1115/IMECE2004-61023
Li, Feng Chen ; Segawa, Takehiko ; Kawaguchi, Yasuo ; Hishida, Koichi. / Characteristics of low-speed streaks and vortex structures in drag-reduced turbulent channel flow investigated by stereoscopic PIV. American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED. Vol. 260 2004. pp. 855-862
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