On a turbulent wall jet flowing over a circular cylinder

R. Neuendorf, Israel J Wygnanski

Research output: Contribution to journalArticle

68 Citations (Scopus)

Abstract

The effect of surface curvature on the development of a two-dimensional wall jet was investigated experimentally. A comparison was made between a wall jet flowing around a circular cylinder and its plane equivalent. Velocity surveys and surface pressure measurements in the curved wall jet suggest the existence of two primary regions of interest. The first region, ranging from the end of the potential core to an approximate angular position of θ = 120°, is characterized by a constant surface pressure and a self similarity of the mean flow. The second region is marked by an adverse pressure gradient leading to separation around θ = 230°. The rate of spread of this flow, even in the initial region, is much higher than in the plane wall jet and so are the levels of turbulence and Reynolds stress. The dominant lengthscale in this flow is the radius of curvature R and the dominant velocity scale is the square root of the kinematic jet momentum divided by the radius of curvature. Entrainment of ambient fluid which causes the jet to adhere to the curved surface is also the main reason for its separation which is preceded by a rapid rate of spread of the flow leading to the failure of the boundary-layer approximation.

Original languageEnglish (US)
Pages (from-to)1-25
Number of pages25
JournalJournal of Fluid Mechanics
Volume381
StatePublished - Feb 25 1999

Fingerprint

wall jets
circular cylinders
Circular cylinders
curvature
radii
curved surfaces
Reynolds stress
entrainment
pressure measurement
pressure gradients
boundary layers
kinematics
turbulence
Surface measurement
Pressure measurement
Pressure gradient
momentum
causes
fluids
Momentum

ASJC Scopus subject areas

  • Computational Mechanics
  • Mechanics of Materials
  • Physics and Astronomy(all)
  • Condensed Matter Physics

Cite this

On a turbulent wall jet flowing over a circular cylinder. / Neuendorf, R.; Wygnanski, Israel J.

In: Journal of Fluid Mechanics, Vol. 381, 25.02.1999, p. 1-25.

Research output: Contribution to journalArticle

@article{360b2b4140084c37b114730a63a617be,
title = "On a turbulent wall jet flowing over a circular cylinder",
abstract = "The effect of surface curvature on the development of a two-dimensional wall jet was investigated experimentally. A comparison was made between a wall jet flowing around a circular cylinder and its plane equivalent. Velocity surveys and surface pressure measurements in the curved wall jet suggest the existence of two primary regions of interest. The first region, ranging from the end of the potential core to an approximate angular position of θ = 120°, is characterized by a constant surface pressure and a self similarity of the mean flow. The second region is marked by an adverse pressure gradient leading to separation around θ = 230°. The rate of spread of this flow, even in the initial region, is much higher than in the plane wall jet and so are the levels of turbulence and Reynolds stress. The dominant lengthscale in this flow is the radius of curvature R and the dominant velocity scale is the square root of the kinematic jet momentum divided by the radius of curvature. Entrainment of ambient fluid which causes the jet to adhere to the curved surface is also the main reason for its separation which is preceded by a rapid rate of spread of the flow leading to the failure of the boundary-layer approximation.",
author = "R. Neuendorf and Wygnanski, {Israel J}",
year = "1999",
month = "2",
day = "25",
language = "English (US)",
volume = "381",
pages = "1--25",
journal = "Journal of Fluid Mechanics",
issn = "0022-1120",
publisher = "Cambridge University Press",

}

TY - JOUR

T1 - On a turbulent wall jet flowing over a circular cylinder

AU - Neuendorf, R.

AU - Wygnanski, Israel J

PY - 1999/2/25

Y1 - 1999/2/25

N2 - The effect of surface curvature on the development of a two-dimensional wall jet was investigated experimentally. A comparison was made between a wall jet flowing around a circular cylinder and its plane equivalent. Velocity surveys and surface pressure measurements in the curved wall jet suggest the existence of two primary regions of interest. The first region, ranging from the end of the potential core to an approximate angular position of θ = 120°, is characterized by a constant surface pressure and a self similarity of the mean flow. The second region is marked by an adverse pressure gradient leading to separation around θ = 230°. The rate of spread of this flow, even in the initial region, is much higher than in the plane wall jet and so are the levels of turbulence and Reynolds stress. The dominant lengthscale in this flow is the radius of curvature R and the dominant velocity scale is the square root of the kinematic jet momentum divided by the radius of curvature. Entrainment of ambient fluid which causes the jet to adhere to the curved surface is also the main reason for its separation which is preceded by a rapid rate of spread of the flow leading to the failure of the boundary-layer approximation.

AB - The effect of surface curvature on the development of a two-dimensional wall jet was investigated experimentally. A comparison was made between a wall jet flowing around a circular cylinder and its plane equivalent. Velocity surveys and surface pressure measurements in the curved wall jet suggest the existence of two primary regions of interest. The first region, ranging from the end of the potential core to an approximate angular position of θ = 120°, is characterized by a constant surface pressure and a self similarity of the mean flow. The second region is marked by an adverse pressure gradient leading to separation around θ = 230°. The rate of spread of this flow, even in the initial region, is much higher than in the plane wall jet and so are the levels of turbulence and Reynolds stress. The dominant lengthscale in this flow is the radius of curvature R and the dominant velocity scale is the square root of the kinematic jet momentum divided by the radius of curvature. Entrainment of ambient fluid which causes the jet to adhere to the curved surface is also the main reason for its separation which is preceded by a rapid rate of spread of the flow leading to the failure of the boundary-layer approximation.

UR - http://www.scopus.com/inward/record.url?scp=0032638957&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0032638957&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0032638957

VL - 381

SP - 1

EP - 25

JO - Journal of Fluid Mechanics

JF - Journal of Fluid Mechanics

SN - 0022-1120

ER -