Viscoelastic effect on steady wavy roll cells in wall-bounded shear flow

Tomohiro Nimura, Takuya Kawata, Takahiro Tsukahara

研究成果: Article査読

1 被引用数 (Scopus)

抄録

An alternative step in understanding the flows of near wall drag-reducing turbulence can be examining the flow in a well-organized streamwise vortex with a laminar background. Herein, we studied the flow behaviors of the Giesekus viscoelastic fluid in a rotating plane Couette flow system, which is accompanied by steady roll cell structures. By fixing the Reynolds and rotation numbers at values that provide as steady wavy roll cell, i.e., an array of meandering streamwise vortices, the Weissenberg number was increased up to 2000 (where the relaxation time was normalized by the wall speed and the kinematic viscosity). We observed that, in the viscoelastic flows, the secondary flow (wall-normal and spanwise velocity fluctuations) are suppressed while the streamwise component is maintained, and the wavy roll cells are modulated into streamwise-independent straight roll cells. The kinetic energy transports among the mean shear flow, Reynolds stresses due to the roll cell, and viscoelastic stress are investigated in the non-turbulent background. We further discussed the modulation mechanism and its relevance to the drag reduction phenomenon in the viscoelastic wall turbulence.

本文言語English
論文番号051414
ジャーナルFluid Dynamics Research
50
5
DOI
出版ステータスPublished - 2018 8 23
外部発表はい

ASJC Scopus subject areas

  • 機械工学
  • 物理学および天文学(全般)
  • 流体および伝熱

フィンガープリント

「Viscoelastic effect on steady wavy roll cells in wall-bounded shear flow」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル