Settling velocity of particles in a grid-generated turbulence

Research output: Contribution to journalArticle

Abstract

The purpose of this study is to examine the retardation of the settling velocity of a particle in the turbulent flow generated by an oscillating grid through a numerical simulation and a hydraulic experiment. First, we measured trajectories of glass beads in a grid-generated turbulence to verify the validity of the numerical simulation for particle behavior. Next, we examined the dynamic response of particles utilizing wavelet analysis and the relationship between the retardation of the mean settling velocity and the turbulent characteristic. As a result, we could identify low-frequency components that particles would easily follow, and high-frequency components that would affect the motion of particles in vertical fluid velocity fluctuations, respectively. Furthermore, it was found that the retardation of the mean settling velocity depends on the spectral distribution of high-frequency, and that the retardation rates increase with increases in turbulent intensity.

Original languageEnglish
Pages (from-to)385-402
Number of pages18
JournalJournal of the Faculty of Agriculture, Kyushu University
Volume44
Issue number3-4
Publication statusPublished - Feb 2000

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Wavelet Analysis
Glass
turbulent flow
trajectories
glass
fluid mechanics

All Science Journal Classification (ASJC) codes

  • Agricultural and Biological Sciences (miscellaneous)

Cite this

Settling velocity of particles in a grid-generated turbulence. / Masayoshi, Harada; Hiramatsu, Kazuaki; Hayashi, Shizuo.

In: Journal of the Faculty of Agriculture, Kyushu University, Vol. 44, No. 3-4, 02.2000, p. 385-402.

Research output: Contribution to journalArticle

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