Effect of atmospheric boundary layer stability on the inclination angle of turbulence coherent structures

Eslam Reda Lotfy, Zambri Harun

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Coherent structures in the atmospheric boundary layer are fundamental to the transport of momentum and heat as well as to the production of turbulence. The present work attempts to investigate the behavior of the inclination angle of the vortex packet structures ((Formula presented.)) under different stability conditions. The data were collected from the Marine Ecosystem Research Centre (EKOMAR) site at the east coast of Peninsular Malaysia. The main measurements were conducted by placing two hotwires 3 and 12 m above ground. The two-point correlation method was used to calculate the vortex packet structure inclination angle, while the one-point correlation method was employed to calculate its length-scale. The inclination angle was found to increase under both stable and unstable conditions. As the Obukhov stability parameter ((Formula presented.)) approaches 0, the inclination angle ranged between (Formula presented.) to (Formula presented.) for the stable and unstable conditions, respectively, which agrees with the findings of previous research. The vertical gradient of velocity is the dominant parameter affecting the inclination angle under different stability conditions.

Original languageEnglish
Pages (from-to)1-23
Number of pages23
JournalEnvironmental Fluid Mechanics
DOIs
Publication statusAccepted/In press - 11 Nov 2017

Fingerprint

Atmospheric boundary layer
vortex
Turbulence
Correlation methods
boundary layer
turbulence
Vortex flow
marine ecosystem
momentum
Aquatic ecosystems
Coastal zones
coast
Momentum
effect
method
parameter
ecosystem research
research centre

Keywords

  • Atmospheric boundary layer
  • Coherent structure
  • Inclination angle
  • Turbulence

ASJC Scopus subject areas

  • Environmental Chemistry
  • Water Science and Technology

Cite this

Effect of atmospheric boundary layer stability on the inclination angle of turbulence coherent structures. / Lotfy, Eslam Reda; Harun, Zambri.

In: Environmental Fluid Mechanics, 11.11.2017, p. 1-23.

Research output: Contribution to journalArticle

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