Mixing characteristics of inclined fuel injection via various geometries for upstream-fuel-injected scramjets

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

Efficient fuel/air mixing plays a crucial role in successful operation of hypersonic airbreathing engines, particularly scramjets, where fuel must be injected into high-speed crossflow and mixed with air at an extremely short timescale. This paper presents the results of a numerical study that investigates the effects of various orifice shapes on fuel mixing characteristics into hypersonic airflow at Mach 5, aiming at the application to scramjet operation with upstream fuel injection at Mach 10. The performance of the injectors at an inclination angle of 45 deg are assessed with respect to various criteria such as the mixing efficiency, streamwise circulation, total pressure recovery, fuel penetration, and spread. Streamwise slot injectors have been found to yield higher mixing efficiency than the other injectors tested (namely, square, circular, diamond, and triangular injectors), owing to the buffering effects. Apparent higher total pressure recovery has been obtained with these rectangular injectors, but their advantages have diminished significantly with the alignment of the trailing-edge position. The highest vertical penetration has been achieved by the square injector, whereas the performances of other injectors with a sharp leading edge have been found to be affected considerably by the axis switch phenomenon due to inclined injection at higher injection pressure. A major influence of the fore and aft shapes of the orifice has been observed on the three-dimensional bow shock formation and wake recirculation, respectively.

Original languageEnglish
Pages (from-to)1551-1566
Number of pages16
JournalJournal of Propulsion and Power
Volume31
Issue number6
DOIs
Publication statusPublished - Jan 1 2015

Fingerprint

fuel injection
supersonic combustion ramjet engines
Fuel injection
injectors
upstream
geometry
Geometry
Hypersonic aerodynamics
Orifices
Mach number
pressure recovery
hypersonics
Recovery
penetration
orifices
Air
sharp leading edges
air
Diamonds
buffering

All Science Journal Classification (ASJC) codes

  • Aerospace Engineering
  • Fuel Technology
  • Mechanical Engineering
  • Space and Planetary Science

Cite this

Mixing characteristics of inclined fuel injection via various geometries for upstream-fuel-injected scramjets. / Ogawa, Hideaki.

In: Journal of Propulsion and Power, Vol. 31, No. 6, 01.01.2015, p. 1551-1566.

Research output: Contribution to journalArticle

@article{cada0d75fecc4192ac2bad523efee825,
title = "Mixing characteristics of inclined fuel injection via various geometries for upstream-fuel-injected scramjets",
abstract = "Efficient fuel/air mixing plays a crucial role in successful operation of hypersonic airbreathing engines, particularly scramjets, where fuel must be injected into high-speed crossflow and mixed with air at an extremely short timescale. This paper presents the results of a numerical study that investigates the effects of various orifice shapes on fuel mixing characteristics into hypersonic airflow at Mach 5, aiming at the application to scramjet operation with upstream fuel injection at Mach 10. The performance of the injectors at an inclination angle of 45 deg are assessed with respect to various criteria such as the mixing efficiency, streamwise circulation, total pressure recovery, fuel penetration, and spread. Streamwise slot injectors have been found to yield higher mixing efficiency than the other injectors tested (namely, square, circular, diamond, and triangular injectors), owing to the buffering effects. Apparent higher total pressure recovery has been obtained with these rectangular injectors, but their advantages have diminished significantly with the alignment of the trailing-edge position. The highest vertical penetration has been achieved by the square injector, whereas the performances of other injectors with a sharp leading edge have been found to be affected considerably by the axis switch phenomenon due to inclined injection at higher injection pressure. A major influence of the fore and aft shapes of the orifice has been observed on the three-dimensional bow shock formation and wake recirculation, respectively.",
author = "Hideaki Ogawa",
year = "2015",
month = "1",
day = "1",
doi = "10.2514/1.B35581",
language = "English",
volume = "31",
pages = "1551--1566",
journal = "Journal of Propulsion and Power",
issn = "0748-4658",
publisher = "American Institute of Aeronautics and Astronautics Inc. (AIAA)",
number = "6",

}

TY - JOUR

T1 - Mixing characteristics of inclined fuel injection via various geometries for upstream-fuel-injected scramjets

AU - Ogawa, Hideaki

PY - 2015/1/1

Y1 - 2015/1/1

N2 - Efficient fuel/air mixing plays a crucial role in successful operation of hypersonic airbreathing engines, particularly scramjets, where fuel must be injected into high-speed crossflow and mixed with air at an extremely short timescale. This paper presents the results of a numerical study that investigates the effects of various orifice shapes on fuel mixing characteristics into hypersonic airflow at Mach 5, aiming at the application to scramjet operation with upstream fuel injection at Mach 10. The performance of the injectors at an inclination angle of 45 deg are assessed with respect to various criteria such as the mixing efficiency, streamwise circulation, total pressure recovery, fuel penetration, and spread. Streamwise slot injectors have been found to yield higher mixing efficiency than the other injectors tested (namely, square, circular, diamond, and triangular injectors), owing to the buffering effects. Apparent higher total pressure recovery has been obtained with these rectangular injectors, but their advantages have diminished significantly with the alignment of the trailing-edge position. The highest vertical penetration has been achieved by the square injector, whereas the performances of other injectors with a sharp leading edge have been found to be affected considerably by the axis switch phenomenon due to inclined injection at higher injection pressure. A major influence of the fore and aft shapes of the orifice has been observed on the three-dimensional bow shock formation and wake recirculation, respectively.

AB - Efficient fuel/air mixing plays a crucial role in successful operation of hypersonic airbreathing engines, particularly scramjets, where fuel must be injected into high-speed crossflow and mixed with air at an extremely short timescale. This paper presents the results of a numerical study that investigates the effects of various orifice shapes on fuel mixing characteristics into hypersonic airflow at Mach 5, aiming at the application to scramjet operation with upstream fuel injection at Mach 10. The performance of the injectors at an inclination angle of 45 deg are assessed with respect to various criteria such as the mixing efficiency, streamwise circulation, total pressure recovery, fuel penetration, and spread. Streamwise slot injectors have been found to yield higher mixing efficiency than the other injectors tested (namely, square, circular, diamond, and triangular injectors), owing to the buffering effects. Apparent higher total pressure recovery has been obtained with these rectangular injectors, but their advantages have diminished significantly with the alignment of the trailing-edge position. The highest vertical penetration has been achieved by the square injector, whereas the performances of other injectors with a sharp leading edge have been found to be affected considerably by the axis switch phenomenon due to inclined injection at higher injection pressure. A major influence of the fore and aft shapes of the orifice has been observed on the three-dimensional bow shock formation and wake recirculation, respectively.

UR - http://www.scopus.com/inward/record.url?scp=84946849796&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84946849796&partnerID=8YFLogxK

U2 - 10.2514/1.B35581

DO - 10.2514/1.B35581

M3 - Article

AN - SCOPUS:84946849796

VL - 31

SP - 1551

EP - 1566

JO - Journal of Propulsion and Power

JF - Journal of Propulsion and Power

SN - 0748-4658

IS - 6

ER -