Passive control of pressure oscillations in hypersonic cavity flow
Author : Shiaw-wuu Perng
Publisher :
Page : 260 pages
File Size : 34,9 MB
Release : 1996
Category : Aerodynamics, Hypersonic
ISBN :
Author : Shiaw-wuu Perng
Publisher :
Page : 260 pages
File Size : 34,9 MB
Release : 1996
Category : Aerodynamics, Hypersonic
ISBN :
Author : D. S. Dolling
Publisher :
Page : 140 pages
File Size : 10,50 MB
Release : 1998
Category : Aerodynamics, Hypersonic
ISBN :
An experimental study of open cavity flow has been made in a high Reynolds number, Mach 5 turbulent boundary layer. The majority of measurements made were of fluctuating wall pressures. The objectives were: (1) examine how effective changes in front and rear wall geometry were at attenuating the pressure oscillations, (2) explore how impingement of a shock wave (variable strength and position) the cavity flow, and (3) how stores (different geometries and positions) affected the cavity flow. In addition, techniques which were judged effective at attenuating pressure oscillations for the empty cavity were used with shock impingement and with stores in order to explore their effectiveness under perturbed flow conditions. The results show that vented and slotted walls, and spoilers are ineffective. A 3-D rear wall (swept in both planes and symmetric about the center line) attenuated the strongest oscillations by factors of up to 7 compared to the baseline rectangular cavity. Regardless of shock impingement position, shock strength, store position, store dimensions, store to cavity volume ratio and asymmetric store arrangement the cavity oscillation frequencies remain essentially unchanged. Based on the mean and rms Pressure distributions (whose magnitude varies substantially but whose basic shape does not change significantly) and surface flow patterns it appears that the essential flow structure also remains largely unchanged. These similarities suggest that control techniques developed for the empty cavity flow should be effective with shock impingement or store release. Tests using two passive control rear walls in perturbed cavity flow support this conclusion.
Author : Mostafa Barzegar Gerdroodbary
Publisher : Butterworth-Heinemann
Page : 230 pages
File Size : 38,8 MB
Release : 2020-07-21
Category : Technology & Engineering
ISBN : 0128211407
Scramjet engines are a type of jet engine and rely on the combustion of fuel and an oxidizer to produce thrust. While scramjets are conceptually simple, actual implementation is limited by extreme technical challenges. Hypersonic flight within the atmosphere generates immense drag, and temperatures found on the aircraft and within the engine can be much greater than that of the surrounding air. Maintaining combustion in the supersonic flow presents additional challenges, as the fuel must be injected, mixed, ignited, and burned within milliseconds. Fuel mixing, along with the configuration and positioning of the injectors and the boundary conditions, play a key role in combustion efficiency. Scramjets: Fuel Mixing and Injection Systems discusses how fuel mixing efficiency and the advantage of injection systems can enhance the performance of the scramjets. The book begins with the introduction of the supersonic combustion chamber and explains the main parameters on the mixing rate. The configuration of scramjets is then introduced with special emphasis on the main effective parameters on the mixing of fuel inside the scramjets. In addition, basic concepts and principles on the mixing rate and fuel distribution within scramjets are presented. Main effective parameters such as range of fuel concentration for the efficient combustion, pressure of fuel jet and various arrangement of jet injections are also explained. This book is for aeronautical and mechanical engineers as well as those working in supersonic combustion who need to know the effects of compressibility on combustion, of shocks on mixing and on chemical reactions, and vorticity on the flame anchoring. - Explains the main applicable approaches for enhancement of supersonic combustion engines and the new techniques of fuel injection - Shows how the interaction of main air stream with fuel injections can develop the mixing inside the scramjets - Presents results of numerical simulations and how they can be used for the development of the combustion engines
Author : American Institute of Aeronautics and Astronautics
Publisher :
Page : 868 pages
File Size : 21,87 MB
Release : 2005
Category : Aeronautics
ISBN :
Author :
Publisher :
Page : 686 pages
File Size : 44,12 MB
Release : 1997
Category : Fluid dynamics
ISBN :
Author :
Publisher :
Page : 636 pages
File Size : 15,51 MB
Release : 1998
Category : Airplanes
ISBN :
Author :
Publisher :
Page : 500 pages
File Size : 18,79 MB
Release : 1999
Category : Airplanes
ISBN :
Author :
Publisher :
Page : 714 pages
File Size : 20,88 MB
Release : 1999
Category : Aeronautics
ISBN :
Author :
Publisher :
Page : 636 pages
File Size : 47,72 MB
Release : 2004
Category : Aeronautics
ISBN :
Author :
Publisher :
Page : 1016 pages
File Size : 48,75 MB
Release : 1999
Category : Aeronautics
ISBN :