Combustion zone-acoustic cavity interactions in rocket combustors

Tom L Acker, Charles E. Mitchell

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

Analytical and numerical models are employed to assess the stabilizing impact of acoustic absorbers on liquid propellant rocket engine intrinsic stability. The tuning and stability behavior of cavities in which tow-dimensional flow and temperature variations exist are predicted through the application of an iterative-integral, Green's function method of analysis. Results of stability calculations performed for a variety of cavity geometries and temperature gradients indicate that adding a large open area absorber to a combustion chamber significantly alters the spatial shape of the oscillation. This alteration consequently affects the driving and damping mechanisms in the chamber. Because of this interaction, the maximal stabilizing effect of a cavity with a given open area does not in general occur for a design tuned in the acoustic sense to the frequency of the oscillation, but rather for a design that is not tuned but which tends to maximize the influence of the damping mechanisms in the chamber relative to the driving mechanisms. Additionally absorbers with large backing cavities. Calculations also reveal that large temperature gradients in an absorber tend to reduce its broadband effectiveness.

Original languageEnglish (US)
Pages (from-to)235-243
Number of pages9
JournalJournal of Propulsion and Power
Volume10
Issue number2
StatePublished - Mar 1994
Externally publishedYes

Fingerprint

combustion chambers
Rockets
rockets
Combustors
absorbers
cavity
acoustics
combustion
Acoustics
Thermal gradients
cavities
Damping
temperature gradient
Liquid propellants
damping
temperature gradients
liquid propellant rocket engines
chambers
oscillation
Rocket engines

ASJC Scopus subject areas

  • Aerospace Engineering

Cite this

Combustion zone-acoustic cavity interactions in rocket combustors. / Acker, Tom L; Mitchell, Charles E.

In: Journal of Propulsion and Power, Vol. 10, No. 2, 03.1994, p. 235-243.

Research output: Contribution to journalArticle

@article{fce6a7a4e01b46fe8ab7f119be549921,
title = "Combustion zone-acoustic cavity interactions in rocket combustors",
abstract = "Analytical and numerical models are employed to assess the stabilizing impact of acoustic absorbers on liquid propellant rocket engine intrinsic stability. The tuning and stability behavior of cavities in which tow-dimensional flow and temperature variations exist are predicted through the application of an iterative-integral, Green's function method of analysis. Results of stability calculations performed for a variety of cavity geometries and temperature gradients indicate that adding a large open area absorber to a combustion chamber significantly alters the spatial shape of the oscillation. This alteration consequently affects the driving and damping mechanisms in the chamber. Because of this interaction, the maximal stabilizing effect of a cavity with a given open area does not in general occur for a design tuned in the acoustic sense to the frequency of the oscillation, but rather for a design that is not tuned but which tends to maximize the influence of the damping mechanisms in the chamber relative to the driving mechanisms. Additionally absorbers with large backing cavities. Calculations also reveal that large temperature gradients in an absorber tend to reduce its broadband effectiveness.",
author = "Acker, {Tom L} and Mitchell, {Charles E.}",
year = "1994",
month = "3",
language = "English (US)",
volume = "10",
pages = "235--243",
journal = "Journal of Propulsion and Power",
issn = "0748-4658",
publisher = "American Institute of Aeronautics and Astronautics Inc. (AIAA)",
number = "2",

}

TY - JOUR

T1 - Combustion zone-acoustic cavity interactions in rocket combustors

AU - Acker, Tom L

AU - Mitchell, Charles E.

PY - 1994/3

Y1 - 1994/3

N2 - Analytical and numerical models are employed to assess the stabilizing impact of acoustic absorbers on liquid propellant rocket engine intrinsic stability. The tuning and stability behavior of cavities in which tow-dimensional flow and temperature variations exist are predicted through the application of an iterative-integral, Green's function method of analysis. Results of stability calculations performed for a variety of cavity geometries and temperature gradients indicate that adding a large open area absorber to a combustion chamber significantly alters the spatial shape of the oscillation. This alteration consequently affects the driving and damping mechanisms in the chamber. Because of this interaction, the maximal stabilizing effect of a cavity with a given open area does not in general occur for a design tuned in the acoustic sense to the frequency of the oscillation, but rather for a design that is not tuned but which tends to maximize the influence of the damping mechanisms in the chamber relative to the driving mechanisms. Additionally absorbers with large backing cavities. Calculations also reveal that large temperature gradients in an absorber tend to reduce its broadband effectiveness.

AB - Analytical and numerical models are employed to assess the stabilizing impact of acoustic absorbers on liquid propellant rocket engine intrinsic stability. The tuning and stability behavior of cavities in which tow-dimensional flow and temperature variations exist are predicted through the application of an iterative-integral, Green's function method of analysis. Results of stability calculations performed for a variety of cavity geometries and temperature gradients indicate that adding a large open area absorber to a combustion chamber significantly alters the spatial shape of the oscillation. This alteration consequently affects the driving and damping mechanisms in the chamber. Because of this interaction, the maximal stabilizing effect of a cavity with a given open area does not in general occur for a design tuned in the acoustic sense to the frequency of the oscillation, but rather for a design that is not tuned but which tends to maximize the influence of the damping mechanisms in the chamber relative to the driving mechanisms. Additionally absorbers with large backing cavities. Calculations also reveal that large temperature gradients in an absorber tend to reduce its broadband effectiveness.

UR - http://www.scopus.com/inward/record.url?scp=0028392154&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0028392154&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0028392154

VL - 10

SP - 235

EP - 243

JO - Journal of Propulsion and Power

JF - Journal of Propulsion and Power

SN - 0748-4658

IS - 2

ER -