Localized Modification of Turbulent Spectra in a Horizontal Mixing Layer by Introducing Microbubbles

  • WATAMURA Tomoaki
    北海道大学 大学院工学院 エネルギー環境システム専攻
  • TASAKA Yuji
    北海道大学 大学院工学院 エネルギー環境システム専攻
  • MURAI Yuichi
    北海道大学 大学院工学院 エネルギー環境システム専攻

Bibliographic Information

Other Title
  • マイクロバブルの導入による水平混合層の局所的乱流スペクトル変形
  • マイクロバブル ノ ドウニュウ ニ ヨル スイヘイ コンゴウソウ ノ キョクショテキ ランリュウ スペクトル ヘンケイ

Search this article

Abstract

In order to investigate the modifications of spatial-temporal developing flows by adding microbubbles in O(10 μm) diameter, flow structures appearing in shear flows of a horizontal mixing layer are visualized from velocity distributions obtained by (I) image analysis combining particle tracking velocimetry (PTV) and laser induced fluorescence (LIF), and (II) ultrasound velocity profiling (UVP). As the result of measurement, Reynolds shear stress is increased by introducing microbubbles at the early stage of the mixing-layer. In the developing region, however, Reynolds shear stress is flattened at the center of mixing layer and is reduced in bulk. Energy spectra of the velocity fluctuations show that energy of flow structures, whose length scale is as equivalent to the initial vortex layer thickness, is partially reduced. The size of vortex layer thickness is enlarged due to the local modification of the flow structures appearing in the early stage of mixing-layer.

Journal

References(7)*help

See more

Related Projects

See more

Details 詳細情報について

Report a problem

Back to top