Implicit large eddy simulation of a scalar mixing layer in fractal grid turbulence

Tomoaki Watanabe, Yasuhiko Sakai, Kouji Nagata, Yasumasa Ito, Toshiyuki Hayase

Research output: Contribution to journalArticlepeer-review

6 Citations (Scopus)

Abstract

A scalar mixing layer in fractal grid turbulence is simulated by the implicit large eddy simulation (ILES) using low-pass filtering as an implicit subgrid-scale model. The square-type fractal grid with three fractal iterations is used for generating turbulence. The streamwise evolutions of the streamwise velocity statistics obtained in the ILES are in good agreement with the experimental results. The ILES results are used for investigating the development of the scalar mixing layer behind the fractal grid. The results show that the vertical development of the scalar mixing layer strongly depends on the spanwise location. Near the fractal grid, the scalar mixing layer rapidly develops just behind the largest grid bars owing to the vertical turbulent transport. The scalar mixing layer near the fractal grid also develops outside the largest grid bars because the scalar is transported between the outside and back of the largest grid bars by the spanwise turbulent transport. In the downstream region, the scalar mixing layer develops more rapidly near the grid centerline by the vertical turbulent transport and by the spanwise one which transports the scalar between the back of the largest grid bars and both the centerline and outer edge of the fractal grid. Then, the mean scalar profile becomes close to be homogeneous in the spanwise direction.

Original languageEnglish
Article number074007
JournalPhysica Scripta
Volume91
Issue number7
DOIs
Publication statusPublished - 2016 Jun 27

Keywords

  • large eddy simulation
  • mixing
  • turbulence
  • turbulent diffusion

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Mathematical Physics
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Implicit large eddy simulation of a scalar mixing layer in fractal grid turbulence'. Together they form a unique fingerprint.

Cite this