Drag reduction capability of uniform blowing in supersonic wall-bounded turbulent flows

Yukinori Kametani, Ayane Kotake, Koji Fukagata, Naoko Tokugawa

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Drag reduction capability of uniform blowing in supersonic turbulent boundary layers is investigated by means of direct numerical simulation of channel flows with uniform blowing on one side and suction on the other. The bulk Reynolds number based on the bulk density, the bulk mean velocity, the channel half-width, and the viscosity on the wall is set to Reb=3000. The bulk Mach number is set at 0.8 and 1.5 to investigate a subsonic and a supersonic condition, respectively. The amplitude of the blowing or suction is set to be 0.1%, 0.3%, or 0.5% of the bulk mass flow rate. At both Mach numbers, modifications of the mean streamwise velocity profiles with blowing and suction are found to be similar to those in an incompressible turbulent channel flow: The skin friction is reduced on the blowing side, while it is increased on the suction side. As for the drag reducing effect of blowing, the drag reduction rate and net-energy saving rate are hardly affected by the Mach number, while the control gain is increased with the increase of Mach number due to the increased density near the wall. The compressibility effect of drag reduction and enhancement is also examined using the physical decomposition of the skin friction drag. A noticeable Mach number effect is found only for the contribution terms containing the viscosity, which is increased by the increased temperature.

Original languageEnglish
Article number123904
JournalPhysical Review Fluids
Volume2
Issue number12
DOIs
Publication statusPublished - 2017 Dec 1

Fingerprint

Drag Reduction
Drag reduction
Blow molding
Turbulent Flow
Turbulent flow
Suction
Mach number
Skin Friction
Drag
Skin friction
Channel flow
Viscosity
Turbulent Channel Flow
Turbulent Boundary Layer
Channel Flow
Compressibility
Velocity Profile
Energy Saving
Gain control
Flow Rate

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes
  • Computational Mechanics
  • Modelling and Simulation

Cite this

Drag reduction capability of uniform blowing in supersonic wall-bounded turbulent flows. / Kametani, Yukinori; Kotake, Ayane; Fukagata, Koji; Tokugawa, Naoko.

In: Physical Review Fluids, Vol. 2, No. 12, 123904, 01.12.2017.

Research output: Contribution to journalArticle

Kametani, Yukinori ; Kotake, Ayane ; Fukagata, Koji ; Tokugawa, Naoko. / Drag reduction capability of uniform blowing in supersonic wall-bounded turbulent flows. In: Physical Review Fluids. 2017 ; Vol. 2, No. 12.
@article{79ef726aabde439c9a28bb85febf7c42,
title = "Drag reduction capability of uniform blowing in supersonic wall-bounded turbulent flows",
abstract = "Drag reduction capability of uniform blowing in supersonic turbulent boundary layers is investigated by means of direct numerical simulation of channel flows with uniform blowing on one side and suction on the other. The bulk Reynolds number based on the bulk density, the bulk mean velocity, the channel half-width, and the viscosity on the wall is set to Reb=3000. The bulk Mach number is set at 0.8 and 1.5 to investigate a subsonic and a supersonic condition, respectively. The amplitude of the blowing or suction is set to be 0.1{\%}, 0.3{\%}, or 0.5{\%} of the bulk mass flow rate. At both Mach numbers, modifications of the mean streamwise velocity profiles with blowing and suction are found to be similar to those in an incompressible turbulent channel flow: The skin friction is reduced on the blowing side, while it is increased on the suction side. As for the drag reducing effect of blowing, the drag reduction rate and net-energy saving rate are hardly affected by the Mach number, while the control gain is increased with the increase of Mach number due to the increased density near the wall. The compressibility effect of drag reduction and enhancement is also examined using the physical decomposition of the skin friction drag. A noticeable Mach number effect is found only for the contribution terms containing the viscosity, which is increased by the increased temperature.",
author = "Yukinori Kametani and Ayane Kotake and Koji Fukagata and Naoko Tokugawa",
year = "2017",
month = "12",
day = "1",
doi = "10.1103/PhysRevFluids.2.123904",
language = "English",
volume = "2",
journal = "Physical Review Fluids",
issn = "2469-990X",
publisher = "American Physical Society",
number = "12",

}

TY - JOUR

T1 - Drag reduction capability of uniform blowing in supersonic wall-bounded turbulent flows

AU - Kametani, Yukinori

AU - Kotake, Ayane

AU - Fukagata, Koji

AU - Tokugawa, Naoko

PY - 2017/12/1

Y1 - 2017/12/1

N2 - Drag reduction capability of uniform blowing in supersonic turbulent boundary layers is investigated by means of direct numerical simulation of channel flows with uniform blowing on one side and suction on the other. The bulk Reynolds number based on the bulk density, the bulk mean velocity, the channel half-width, and the viscosity on the wall is set to Reb=3000. The bulk Mach number is set at 0.8 and 1.5 to investigate a subsonic and a supersonic condition, respectively. The amplitude of the blowing or suction is set to be 0.1%, 0.3%, or 0.5% of the bulk mass flow rate. At both Mach numbers, modifications of the mean streamwise velocity profiles with blowing and suction are found to be similar to those in an incompressible turbulent channel flow: The skin friction is reduced on the blowing side, while it is increased on the suction side. As for the drag reducing effect of blowing, the drag reduction rate and net-energy saving rate are hardly affected by the Mach number, while the control gain is increased with the increase of Mach number due to the increased density near the wall. The compressibility effect of drag reduction and enhancement is also examined using the physical decomposition of the skin friction drag. A noticeable Mach number effect is found only for the contribution terms containing the viscosity, which is increased by the increased temperature.

AB - Drag reduction capability of uniform blowing in supersonic turbulent boundary layers is investigated by means of direct numerical simulation of channel flows with uniform blowing on one side and suction on the other. The bulk Reynolds number based on the bulk density, the bulk mean velocity, the channel half-width, and the viscosity on the wall is set to Reb=3000. The bulk Mach number is set at 0.8 and 1.5 to investigate a subsonic and a supersonic condition, respectively. The amplitude of the blowing or suction is set to be 0.1%, 0.3%, or 0.5% of the bulk mass flow rate. At both Mach numbers, modifications of the mean streamwise velocity profiles with blowing and suction are found to be similar to those in an incompressible turbulent channel flow: The skin friction is reduced on the blowing side, while it is increased on the suction side. As for the drag reducing effect of blowing, the drag reduction rate and net-energy saving rate are hardly affected by the Mach number, while the control gain is increased with the increase of Mach number due to the increased density near the wall. The compressibility effect of drag reduction and enhancement is also examined using the physical decomposition of the skin friction drag. A noticeable Mach number effect is found only for the contribution terms containing the viscosity, which is increased by the increased temperature.

UR - http://www.scopus.com/inward/record.url?scp=85040051208&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85040051208&partnerID=8YFLogxK

U2 - 10.1103/PhysRevFluids.2.123904

DO - 10.1103/PhysRevFluids.2.123904

M3 - Article

VL - 2

JO - Physical Review Fluids

JF - Physical Review Fluids

SN - 2469-990X

IS - 12

M1 - 123904

ER -