Turbulence intensity effects on heat transfer and fluid-flow for a circular cylinder in crossflow

J. Ahn, Ephraim M Sparrow, John M Gorman

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The intrinsically unsteady heat transfer on the surface of a cylinder in crossflow has been investigated in detail by numerical simulation as a function of the freestream turbulence intensity and the Reynolds number. After a brief startup transient, a periodic steady state is established at all circumferential locations. The resulting timewise fluctuations were seen to be of different phase depending on where on the circumference they occur. On one side of the cylinder, maxima occurred at the same moment in time as minima occurred on the other side. This finding and comparisons of the magnitudes of the local heat transfer coefficients showed that side-to-side symmetry does not prevail in the presence of the unsteadiness. The fluctuation frequencies were found to be virtually uniform over the entire circumference of the cylinder and varied only slightly with the Reynolds number and the turbulence intensity. The full slate of results included: (a) timewise and circumferential variations of the local heat transfer coefficient, (b) timewise variations of the all-angle spatial-averaged heat transfer coefficient, (c) spatial variations of the timewise-averaged heat transfer coefficient, (d) spatial- and timewise-averaged heat transfer coefficients as a function of turbulence intensity and Reynolds number, (e) timewise fluctuation frequencies, (f) comparisons with the experimental literature, and (g) effect of the selected turbulence model. As expected, the magnitude of the heat transfer coefficient increases as the turbulence intensity increases.

Original languageEnglish (US)
Pages (from-to)613-621
Number of pages9
JournalInternational Journal of Heat and Mass Transfer
Volume113
DOIs
StatePublished - Jan 1 2017

Fingerprint

circular cylinders
Circular cylinders
heat transfer coefficients
Heat transfer coefficients
fluid flow
Flow of fluids
Turbulence
heat transfer
turbulence
Heat transfer
Reynolds number
circumferences
Slate
turbulence models
Turbulence models
moments
Computer simulation
symmetry
simulation

Keywords

  • CFD
  • Cylinder in crossflow
  • Heat transfer
  • Nusselt correlation
  • Turbulence intensity

Cite this

Turbulence intensity effects on heat transfer and fluid-flow for a circular cylinder in crossflow. / Ahn, J.; Sparrow, Ephraim M; Gorman, John M.

In: International Journal of Heat and Mass Transfer, Vol. 113, 01.01.2017, p. 613-621.

Research output: Contribution to journalArticle

@article{4a490bef9b544230bd2629381bbe96a0,
title = "Turbulence intensity effects on heat transfer and fluid-flow for a circular cylinder in crossflow",
abstract = "The intrinsically unsteady heat transfer on the surface of a cylinder in crossflow has been investigated in detail by numerical simulation as a function of the freestream turbulence intensity and the Reynolds number. After a brief startup transient, a periodic steady state is established at all circumferential locations. The resulting timewise fluctuations were seen to be of different phase depending on where on the circumference they occur. On one side of the cylinder, maxima occurred at the same moment in time as minima occurred on the other side. This finding and comparisons of the magnitudes of the local heat transfer coefficients showed that side-to-side symmetry does not prevail in the presence of the unsteadiness. The fluctuation frequencies were found to be virtually uniform over the entire circumference of the cylinder and varied only slightly with the Reynolds number and the turbulence intensity. The full slate of results included: (a) timewise and circumferential variations of the local heat transfer coefficient, (b) timewise variations of the all-angle spatial-averaged heat transfer coefficient, (c) spatial variations of the timewise-averaged heat transfer coefficient, (d) spatial- and timewise-averaged heat transfer coefficients as a function of turbulence intensity and Reynolds number, (e) timewise fluctuation frequencies, (f) comparisons with the experimental literature, and (g) effect of the selected turbulence model. As expected, the magnitude of the heat transfer coefficient increases as the turbulence intensity increases.",
keywords = "CFD, Cylinder in crossflow, Heat transfer, Nusselt correlation, Turbulence intensity",
author = "J. Ahn and Sparrow, {Ephraim M} and Gorman, {John M}",
year = "2017",
month = "1",
day = "1",
doi = "10.1016/j.ijheatmasstransfer.2017.05.131",
language = "English (US)",
volume = "113",
pages = "613--621",
journal = "International Journal of Heat and Mass Transfer",
issn = "0017-9310",
publisher = "Elsevier Limited",

}

TY - JOUR

T1 - Turbulence intensity effects on heat transfer and fluid-flow for a circular cylinder in crossflow

AU - Ahn, J.

AU - Sparrow, Ephraim M

AU - Gorman, John M

PY - 2017/1/1

Y1 - 2017/1/1

N2 - The intrinsically unsteady heat transfer on the surface of a cylinder in crossflow has been investigated in detail by numerical simulation as a function of the freestream turbulence intensity and the Reynolds number. After a brief startup transient, a periodic steady state is established at all circumferential locations. The resulting timewise fluctuations were seen to be of different phase depending on where on the circumference they occur. On one side of the cylinder, maxima occurred at the same moment in time as minima occurred on the other side. This finding and comparisons of the magnitudes of the local heat transfer coefficients showed that side-to-side symmetry does not prevail in the presence of the unsteadiness. The fluctuation frequencies were found to be virtually uniform over the entire circumference of the cylinder and varied only slightly with the Reynolds number and the turbulence intensity. The full slate of results included: (a) timewise and circumferential variations of the local heat transfer coefficient, (b) timewise variations of the all-angle spatial-averaged heat transfer coefficient, (c) spatial variations of the timewise-averaged heat transfer coefficient, (d) spatial- and timewise-averaged heat transfer coefficients as a function of turbulence intensity and Reynolds number, (e) timewise fluctuation frequencies, (f) comparisons with the experimental literature, and (g) effect of the selected turbulence model. As expected, the magnitude of the heat transfer coefficient increases as the turbulence intensity increases.

AB - The intrinsically unsteady heat transfer on the surface of a cylinder in crossflow has been investigated in detail by numerical simulation as a function of the freestream turbulence intensity and the Reynolds number. After a brief startup transient, a periodic steady state is established at all circumferential locations. The resulting timewise fluctuations were seen to be of different phase depending on where on the circumference they occur. On one side of the cylinder, maxima occurred at the same moment in time as minima occurred on the other side. This finding and comparisons of the magnitudes of the local heat transfer coefficients showed that side-to-side symmetry does not prevail in the presence of the unsteadiness. The fluctuation frequencies were found to be virtually uniform over the entire circumference of the cylinder and varied only slightly with the Reynolds number and the turbulence intensity. The full slate of results included: (a) timewise and circumferential variations of the local heat transfer coefficient, (b) timewise variations of the all-angle spatial-averaged heat transfer coefficient, (c) spatial variations of the timewise-averaged heat transfer coefficient, (d) spatial- and timewise-averaged heat transfer coefficients as a function of turbulence intensity and Reynolds number, (e) timewise fluctuation frequencies, (f) comparisons with the experimental literature, and (g) effect of the selected turbulence model. As expected, the magnitude of the heat transfer coefficient increases as the turbulence intensity increases.

KW - CFD

KW - Cylinder in crossflow

KW - Heat transfer

KW - Nusselt correlation

KW - Turbulence intensity

UR - http://www.scopus.com/inward/record.url?scp=85020162671&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85020162671&partnerID=8YFLogxK

U2 - 10.1016/j.ijheatmasstransfer.2017.05.131

DO - 10.1016/j.ijheatmasstransfer.2017.05.131

M3 - Article

AN - SCOPUS:85020162671

VL - 113

SP - 613

EP - 621

JO - International Journal of Heat and Mass Transfer

JF - International Journal of Heat and Mass Transfer

SN - 0017-9310

ER -