Drag reduction in spatially developing turbulent boundary layers by blowing at constant mass-flux

Yukinori Kametani, Ramis Orlii, Koji Fukagata, Philipp Schlatter

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

A series of large-eddy simulations of spatially developing turbulent boundary layers with uniform blowing at moderate Reynolds numbers (based on free-stream velocity, U and momentum thickness, θ) up to Reθ ∼ 2500 were performed with the special focus on the effect of intermittent (separated in streamwise direction) blowing sections. The number of blowing sections, N, investigated is set to be 3, 6, 20, 30 and compared to N = 1, which constitutes the reference case, while the total wall-mass flux is constrained to be the same for all considered cases, corresponding to a blowing amplitude of 0.1% of U for the reference case. Results indicate that the reference case provides a net-energy saving rate of around 18%, which initially decreases at most 2 percentage points for N = 3 but recovers with increasing N. The initial reduction of the drag reduction is due to the shorter streamwise length of intermittent blowing sections. The physical decomposition of the skin friction drag through the FIK identity (Fukagata et at, 2002), shows that the distribution of all components over each blowing section has similar trends, resulting in similar averaged values over the whole control region.

Original languageEnglish
Title of host publication9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015
PublisherTSFP-9
Volume1
ISBN (Electronic)9780000000002
Publication statusPublished - 2015 Jan 1
Event9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015 - Melbourne, Australia
Duration: 2015 Jun 302015 Jul 3

Other

Other9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015
CountryAustralia
CityMelbourne
Period15/6/3015/7/3

Fingerprint

Drag reduction
Blow molding
Boundary layers
Mass transfer
Skin friction
Large eddy simulation
Drag
Momentum
Energy conservation
Reynolds number
Decomposition

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes

Cite this

Kametani, Y., Orlii, R., Fukagata, K., & Schlatter, P. (2015). Drag reduction in spatially developing turbulent boundary layers by blowing at constant mass-flux. In 9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015 (Vol. 1). TSFP-9.

Drag reduction in spatially developing turbulent boundary layers by blowing at constant mass-flux. / Kametani, Yukinori; Orlii, Ramis; Fukagata, Koji; Schlatter, Philipp.

9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015. Vol. 1 TSFP-9, 2015.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Kametani, Y, Orlii, R, Fukagata, K & Schlatter, P 2015, Drag reduction in spatially developing turbulent boundary layers by blowing at constant mass-flux. in 9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015. vol. 1, TSFP-9, 9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015, Melbourne, Australia, 15/6/30.
Kametani Y, Orlii R, Fukagata K, Schlatter P. Drag reduction in spatially developing turbulent boundary layers by blowing at constant mass-flux. In 9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015. Vol. 1. TSFP-9. 2015
Kametani, Yukinori ; Orlii, Ramis ; Fukagata, Koji ; Schlatter, Philipp. / Drag reduction in spatially developing turbulent boundary layers by blowing at constant mass-flux. 9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015. Vol. 1 TSFP-9, 2015.
@inproceedings{4d224b32f70c44c185adc1a12e2350bd,
title = "Drag reduction in spatially developing turbulent boundary layers by blowing at constant mass-flux",
abstract = "A series of large-eddy simulations of spatially developing turbulent boundary layers with uniform blowing at moderate Reynolds numbers (based on free-stream velocity, U∞ and momentum thickness, θ) up to Reθ ∼ 2500 were performed with the special focus on the effect of intermittent (separated in streamwise direction) blowing sections. The number of blowing sections, N, investigated is set to be 3, 6, 20, 30 and compared to N = 1, which constitutes the reference case, while the total wall-mass flux is constrained to be the same for all considered cases, corresponding to a blowing amplitude of 0.1{\%} of U∞ for the reference case. Results indicate that the reference case provides a net-energy saving rate of around 18{\%}, which initially decreases at most 2 percentage points for N = 3 but recovers with increasing N. The initial reduction of the drag reduction is due to the shorter streamwise length of intermittent blowing sections. The physical decomposition of the skin friction drag through the FIK identity (Fukagata et at, 2002), shows that the distribution of all components over each blowing section has similar trends, resulting in similar averaged values over the whole control region.",
author = "Yukinori Kametani and Ramis Orlii and Koji Fukagata and Philipp Schlatter",
year = "2015",
month = "1",
day = "1",
language = "English",
volume = "1",
booktitle = "9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015",
publisher = "TSFP-9",

}

TY - GEN

T1 - Drag reduction in spatially developing turbulent boundary layers by blowing at constant mass-flux

AU - Kametani, Yukinori

AU - Orlii, Ramis

AU - Fukagata, Koji

AU - Schlatter, Philipp

PY - 2015/1/1

Y1 - 2015/1/1

N2 - A series of large-eddy simulations of spatially developing turbulent boundary layers with uniform blowing at moderate Reynolds numbers (based on free-stream velocity, U∞ and momentum thickness, θ) up to Reθ ∼ 2500 were performed with the special focus on the effect of intermittent (separated in streamwise direction) blowing sections. The number of blowing sections, N, investigated is set to be 3, 6, 20, 30 and compared to N = 1, which constitutes the reference case, while the total wall-mass flux is constrained to be the same for all considered cases, corresponding to a blowing amplitude of 0.1% of U∞ for the reference case. Results indicate that the reference case provides a net-energy saving rate of around 18%, which initially decreases at most 2 percentage points for N = 3 but recovers with increasing N. The initial reduction of the drag reduction is due to the shorter streamwise length of intermittent blowing sections. The physical decomposition of the skin friction drag through the FIK identity (Fukagata et at, 2002), shows that the distribution of all components over each blowing section has similar trends, resulting in similar averaged values over the whole control region.

AB - A series of large-eddy simulations of spatially developing turbulent boundary layers with uniform blowing at moderate Reynolds numbers (based on free-stream velocity, U∞ and momentum thickness, θ) up to Reθ ∼ 2500 were performed with the special focus on the effect of intermittent (separated in streamwise direction) blowing sections. The number of blowing sections, N, investigated is set to be 3, 6, 20, 30 and compared to N = 1, which constitutes the reference case, while the total wall-mass flux is constrained to be the same for all considered cases, corresponding to a blowing amplitude of 0.1% of U∞ for the reference case. Results indicate that the reference case provides a net-energy saving rate of around 18%, which initially decreases at most 2 percentage points for N = 3 but recovers with increasing N. The initial reduction of the drag reduction is due to the shorter streamwise length of intermittent blowing sections. The physical decomposition of the skin friction drag through the FIK identity (Fukagata et at, 2002), shows that the distribution of all components over each blowing section has similar trends, resulting in similar averaged values over the whole control region.

UR - http://www.scopus.com/inward/record.url?scp=85034441023&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85034441023&partnerID=8YFLogxK

M3 - Conference contribution

AN - SCOPUS:85034441023

VL - 1

BT - 9th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2015

PB - TSFP-9

ER -