The formation of coherent structures within turbulent fountains in stratified media

被引：5

作者：

Freire, Daniel ^{[1
]}

Kahan, Sandra ^{[1
]}

Cabeza, Cecilia ^{[1
]}

Sarasua, Gustavo ^{[1
]}

Marti, Arturo C. ^{[1
]}

机构：

[1] Univ Republica, Inst Fis, Montevideo, Uruguay

来源：

EUROPEAN JOURNAL OF MECHANICS B-FLUIDS | 2015年 / 50卷

关键词：

Turbulent fountain; Instability; Coherent structures; PROPER-ORTHOGONAL DECOMPOSITION; BREEZE;

D O I：

10.1016/j.euromechflu.2014.11.009

中图分类号：

O3 [力学];

学科分类号：

08 ; 0801 ;

摘要：

An experimental investigation into the interaction between a turbulent fountain and its stratified environment is presented. A heavy fluid, cold water, is injected vertically upwards into a linearly stratified medium. As revealed by visualisations, the heavy-fluid jet reaches a maximum height before it begins to fall under to the effect of gravity. Due to fluid mixing and entrainment, the vertical momentum and the density of the jet fluid decrease as it submerges to an intermediate height of zero buoyancy. Large coherent structures are identified using Proper Orthogonal Decomposition (POD) on Digital Particle Image Velocimetry (DPIV) measurements. Experimental values of the main components of temporal and spatial spectra are compared to predictions based upon the dispersion relations for stratified media. (C) 2014 Elsevier Masson SAS. All rights reserved.

引用

页码：89 / 97

页数：9

共 30 条

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