Numerical computation of turbulent flow in a square-sectioned 180 deg bend

Young Don Choi, H. lacovides, B. E. Launder

Research output: Contribution to journalArticle

80 Citations (Scopus)

Abstract

Fine-grid computations are reported of turbulent flow through a square sectioned U-bend corresponding to that for which Chang et al. (1983a) have provided detailed experimental data. A sequence of modeling refinements is introduced: the replacement of wall functions by a fine mesh across the sublayer; the abandonment of the PSL approximation (in which pressure variations across the near-wall sublayer are neglected); and the introduction of an algebraic second-moment (ASM) closure in place of the usual k-ε eddy-viscosity model. Each refinement is shown to lead to an appreciable improvement in the agreement between measurement and computation. Direct comparisons with the measured rms turbulent velocity give further support to the view that the ASM scheme achieves a generally satisfactory description of the Reynolds stress field. Even with the most refined model some discrepancies between the experiment and computed development are apparent. It is suggested that their removal may require the use of a turbulent transport model in the semi-viscous sublayer in place of the van Driest (1956) mixing-length treatment used at present.

Original languageEnglish
Pages (from-to)59-68
Number of pages10
JournalJournal of Fluids Engineering, Transactions of the ASME
Volume111
Issue number1
DOIs
Publication statusPublished - 1989 Jan 1

Fingerprint

Turbulent flow
Wall function
Viscosity
Experiments

ASJC Scopus subject areas

  • Mechanical Engineering

Cite this

Numerical computation of turbulent flow in a square-sectioned 180 deg bend. / Choi, Young Don; lacovides, H.; Launder, B. E.

In: Journal of Fluids Engineering, Transactions of the ASME, Vol. 111, No. 1, 01.01.1989, p. 59-68.

Research output: Contribution to journalArticle

@article{a576e5df42d342b18babea1e05224aac,
title = "Numerical computation of turbulent flow in a square-sectioned 180 deg bend",
abstract = "Fine-grid computations are reported of turbulent flow through a square sectioned U-bend corresponding to that for which Chang et al. (1983a) have provided detailed experimental data. A sequence of modeling refinements is introduced: the replacement of wall functions by a fine mesh across the sublayer; the abandonment of the PSL approximation (in which pressure variations across the near-wall sublayer are neglected); and the introduction of an algebraic second-moment (ASM) closure in place of the usual k-ε eddy-viscosity model. Each refinement is shown to lead to an appreciable improvement in the agreement between measurement and computation. Direct comparisons with the measured rms turbulent velocity give further support to the view that the ASM scheme achieves a generally satisfactory description of the Reynolds stress field. Even with the most refined model some discrepancies between the experiment and computed development are apparent. It is suggested that their removal may require the use of a turbulent transport model in the semi-viscous sublayer in place of the van Driest (1956) mixing-length treatment used at present.",
author = "Choi, {Young Don} and H. lacovides and Launder, {B. E.}",
year = "1989",
month = "1",
day = "1",
doi = "10.1115/1.3243600",
language = "English",
volume = "111",
pages = "59--68",
journal = "Journal of Fluids Engineering, Transactions of the ASME",
issn = "0098-2202",
publisher = "American Society of Mechanical Engineers(ASME)",
number = "1",

}

TY - JOUR

T1 - Numerical computation of turbulent flow in a square-sectioned 180 deg bend

AU - Choi, Young Don

AU - lacovides, H.

AU - Launder, B. E.

PY - 1989/1/1

Y1 - 1989/1/1

N2 - Fine-grid computations are reported of turbulent flow through a square sectioned U-bend corresponding to that for which Chang et al. (1983a) have provided detailed experimental data. A sequence of modeling refinements is introduced: the replacement of wall functions by a fine mesh across the sublayer; the abandonment of the PSL approximation (in which pressure variations across the near-wall sublayer are neglected); and the introduction of an algebraic second-moment (ASM) closure in place of the usual k-ε eddy-viscosity model. Each refinement is shown to lead to an appreciable improvement in the agreement between measurement and computation. Direct comparisons with the measured rms turbulent velocity give further support to the view that the ASM scheme achieves a generally satisfactory description of the Reynolds stress field. Even with the most refined model some discrepancies between the experiment and computed development are apparent. It is suggested that their removal may require the use of a turbulent transport model in the semi-viscous sublayer in place of the van Driest (1956) mixing-length treatment used at present.

AB - Fine-grid computations are reported of turbulent flow through a square sectioned U-bend corresponding to that for which Chang et al. (1983a) have provided detailed experimental data. A sequence of modeling refinements is introduced: the replacement of wall functions by a fine mesh across the sublayer; the abandonment of the PSL approximation (in which pressure variations across the near-wall sublayer are neglected); and the introduction of an algebraic second-moment (ASM) closure in place of the usual k-ε eddy-viscosity model. Each refinement is shown to lead to an appreciable improvement in the agreement between measurement and computation. Direct comparisons with the measured rms turbulent velocity give further support to the view that the ASM scheme achieves a generally satisfactory description of the Reynolds stress field. Even with the most refined model some discrepancies between the experiment and computed development are apparent. It is suggested that their removal may require the use of a turbulent transport model in the semi-viscous sublayer in place of the van Driest (1956) mixing-length treatment used at present.

UR - http://www.scopus.com/inward/record.url?scp=0024621262&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0024621262&partnerID=8YFLogxK

U2 - 10.1115/1.3243600

DO - 10.1115/1.3243600

M3 - Article

VL - 111

SP - 59

EP - 68

JO - Journal of Fluids Engineering, Transactions of the ASME

JF - Journal of Fluids Engineering, Transactions of the ASME

SN - 0098-2202

IS - 1

ER -