Effect of downstream microjet fluidic injection on mixing characteristics of supersonic jet

Hamideh Pourhashem, Iraj M. Kalkhoran

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

Abstract

The present computational study aims to examine the effectiveness of a downstream microjet fluidic injection (DMFI) scheme in altering the mixing characteristics of supersonic jets in an effort to reduce supersonic jet noise. DMFI scheme, based on our previous experimental study involves perpendicular injection into a supersonic cross flow using four equally spaced injection ports placed on an injection tube which extends downstream of a Mach number 1.5 nozzle. Results of the present numerical investigation indicate good agreement with the previous experimental results; further demonstrating the effectiveness of DMFI scheme in altering the stability characteristics of the shear layer and hence mixing enhancement. The findings suggest that for a constant momentum flux ratio, injection at various axial locations leads to different levels of shear layer penetration. It is shown that perpendicular fluidic injection near the location where local shock wave is expected to occur and subsequent merging of this shock wave with the upstream separation bow shock, modifies the shear layer considerably and results in improved mixing and shear layer spreading. The DMFI scheme shows augmentation of turbulence intensity levels in the vicinity of the nozzle, leading to reduction of downstream turbulence intensities, which consequently influences the noise radiation into the far field.

Original languageEnglish (US)
Title of host publication8th AIAA Flow Control Conference
PublisherAmerican Institute of Aeronautics and Astronautics Inc, AIAA
ISBN (Print)9781624104329
StatePublished - 2016
Event8th AIAA Flow Control Conference, 2016 - Washington, United States
Duration: Jun 13 2016Jun 17 2016

Other

Other8th AIAA Flow Control Conference, 2016
CountryUnited States
CityWashington
Period6/13/166/17/16

Fingerprint

Fluidics
Shock waves
Nozzles
Turbulence
Merging
Mach number
Momentum
Fluxes
Radiation

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes
  • Control and Systems Engineering
  • Aerospace Engineering

Cite this

Pourhashem, H., & Kalkhoran, I. M. (2016). Effect of downstream microjet fluidic injection on mixing characteristics of supersonic jet. In 8th AIAA Flow Control Conference American Institute of Aeronautics and Astronautics Inc, AIAA.

Effect of downstream microjet fluidic injection on mixing characteristics of supersonic jet. / Pourhashem, Hamideh; Kalkhoran, Iraj M.

8th AIAA Flow Control Conference. American Institute of Aeronautics and Astronautics Inc, AIAA, 2016.

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

Pourhashem, H & Kalkhoran, IM 2016, Effect of downstream microjet fluidic injection on mixing characteristics of supersonic jet. in 8th AIAA Flow Control Conference. American Institute of Aeronautics and Astronautics Inc, AIAA, 8th AIAA Flow Control Conference, 2016, Washington, United States, 6/13/16.
Pourhashem H, Kalkhoran IM. Effect of downstream microjet fluidic injection on mixing characteristics of supersonic jet. In 8th AIAA Flow Control Conference. American Institute of Aeronautics and Astronautics Inc, AIAA. 2016
Pourhashem, Hamideh ; Kalkhoran, Iraj M. / Effect of downstream microjet fluidic injection on mixing characteristics of supersonic jet. 8th AIAA Flow Control Conference. American Institute of Aeronautics and Astronautics Inc, AIAA, 2016.
@inproceedings{5efbdc8db4604f30b380fb09c5df4d01,
title = "Effect of downstream microjet fluidic injection on mixing characteristics of supersonic jet",
abstract = "The present computational study aims to examine the effectiveness of a downstream microjet fluidic injection (DMFI) scheme in altering the mixing characteristics of supersonic jets in an effort to reduce supersonic jet noise. DMFI scheme, based on our previous experimental study involves perpendicular injection into a supersonic cross flow using four equally spaced injection ports placed on an injection tube which extends downstream of a Mach number 1.5 nozzle. Results of the present numerical investigation indicate good agreement with the previous experimental results; further demonstrating the effectiveness of DMFI scheme in altering the stability characteristics of the shear layer and hence mixing enhancement. The findings suggest that for a constant momentum flux ratio, injection at various axial locations leads to different levels of shear layer penetration. It is shown that perpendicular fluidic injection near the location where local shock wave is expected to occur and subsequent merging of this shock wave with the upstream separation bow shock, modifies the shear layer considerably and results in improved mixing and shear layer spreading. The DMFI scheme shows augmentation of turbulence intensity levels in the vicinity of the nozzle, leading to reduction of downstream turbulence intensities, which consequently influences the noise radiation into the far field.",
author = "Hamideh Pourhashem and Kalkhoran, {Iraj M.}",
year = "2016",
language = "English (US)",
isbn = "9781624104329",
booktitle = "8th AIAA Flow Control Conference",
publisher = "American Institute of Aeronautics and Astronautics Inc, AIAA",

}

TY - GEN

T1 - Effect of downstream microjet fluidic injection on mixing characteristics of supersonic jet

AU - Pourhashem, Hamideh

AU - Kalkhoran, Iraj M.

PY - 2016

Y1 - 2016

N2 - The present computational study aims to examine the effectiveness of a downstream microjet fluidic injection (DMFI) scheme in altering the mixing characteristics of supersonic jets in an effort to reduce supersonic jet noise. DMFI scheme, based on our previous experimental study involves perpendicular injection into a supersonic cross flow using four equally spaced injection ports placed on an injection tube which extends downstream of a Mach number 1.5 nozzle. Results of the present numerical investigation indicate good agreement with the previous experimental results; further demonstrating the effectiveness of DMFI scheme in altering the stability characteristics of the shear layer and hence mixing enhancement. The findings suggest that for a constant momentum flux ratio, injection at various axial locations leads to different levels of shear layer penetration. It is shown that perpendicular fluidic injection near the location where local shock wave is expected to occur and subsequent merging of this shock wave with the upstream separation bow shock, modifies the shear layer considerably and results in improved mixing and shear layer spreading. The DMFI scheme shows augmentation of turbulence intensity levels in the vicinity of the nozzle, leading to reduction of downstream turbulence intensities, which consequently influences the noise radiation into the far field.

AB - The present computational study aims to examine the effectiveness of a downstream microjet fluidic injection (DMFI) scheme in altering the mixing characteristics of supersonic jets in an effort to reduce supersonic jet noise. DMFI scheme, based on our previous experimental study involves perpendicular injection into a supersonic cross flow using four equally spaced injection ports placed on an injection tube which extends downstream of a Mach number 1.5 nozzle. Results of the present numerical investigation indicate good agreement with the previous experimental results; further demonstrating the effectiveness of DMFI scheme in altering the stability characteristics of the shear layer and hence mixing enhancement. The findings suggest that for a constant momentum flux ratio, injection at various axial locations leads to different levels of shear layer penetration. It is shown that perpendicular fluidic injection near the location where local shock wave is expected to occur and subsequent merging of this shock wave with the upstream separation bow shock, modifies the shear layer considerably and results in improved mixing and shear layer spreading. The DMFI scheme shows augmentation of turbulence intensity levels in the vicinity of the nozzle, leading to reduction of downstream turbulence intensities, which consequently influences the noise radiation into the far field.

UR - http://www.scopus.com/inward/record.url?scp=84979997735&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84979997735&partnerID=8YFLogxK

M3 - Conference contribution

SN - 9781624104329

BT - 8th AIAA Flow Control Conference

PB - American Institute of Aeronautics and Astronautics Inc, AIAA

ER -