Free-jet Testing of a REST Scramjet at Off-Design Conditions

Smart, Michael K. and Ruf, Edward G. (2006). Free-jet Testing of a REST Scramjet at Off-Design Conditions. In: Proceedings of the 25th AIAA Aerodynamic Measurement Technology and Ground Testing Conference. 25th AIAA Aerodynamic Measurement Technology and Ground Testing Conference, San Francisco, California, (2006-2955-1-2006-2955-12). 5-8 June 2006.


Author Smart, Michael K.
Ruf, Edward G.
Title of paper Free-jet Testing of a REST Scramjet at Off-Design Conditions
Conference name 25th AIAA Aerodynamic Measurement Technology and Ground Testing Conference
Conference location San Francisco, California
Conference dates 5-8 June 2006
Convener American Institute of Aeronautics and Astronautics
Proceedings title Proceedings of the 25th AIAA Aerodynamic Measurement Technology and Ground Testing Conference
Place of Publication Hampton, Virginia, U.S.A.
Publisher NASA Langley Research Center
Publication Year 2006
Year available 2006
Sub-type Fully published paper
Start page 2006-2955-1
End page 2006-2955-12
Total pages 12
Language eng
Abstract/Summary Scramjet flowpaths employing elliptical combustors have the potential to improve structural efficiency and performance relative to those using planar geometries. NASA Langley has developed a scramjet flowpath that is integrated into a lifting body vehicle, transitions from a rectangular capture area to an elliptical throat, and includes an elliptical combustor. This Rectangular-to-Elliptical Shape Transition (REST) scramjet has a design point of Mach 7.1, and is intended to operate with fixed-geometry between Mach 4.5 and 8.0. This paper describes initial free-jet testing of a heat-sink REST scramjet engine model at conditions simulating Mach 5.3 flight. Combustion of gaseous hydrogen fuel at equivalence ratios between 0.5 and 1.5 generated robust performance after ignition with a silane-hydrogen pilot. Facilitymodel interactions were experienced for fuel equivalence ratios above 1.1, yet despite this, the flowpath was never unstarted by fuel addition at the Mach 5.3 test condition. Combustion tests resulting in engine unstart at reduced stagnation enthalpy indicated that the inlet/engine self-started following termination of the fuel injection. Engine data is presented for the largest fuel equivalence ratio tested without facility interaction. These results indicate that this class of three-dimensional scramjet engine can operate successfully at off-design conditions.
Subjects 090107 Hypersonic Propulsion and Hypersonic Aerodynamics
Keyword free jets
supersonic combustion ramjet engines
test facilities
computational fluid dynamics
wind tunnel tests
aircraft design
nozzle design
mach number
wall temperature
throats
engine inlets
enthalpy
lifting bodies
Q-Index Code EX

 
Versions
Version Filter Type
Citation counts: Google Scholar Search Google Scholar
Created: Tue, 07 Apr 2009, 13:44:50 EST by Mary-Anne Marrington on behalf of School of Mechanical and Mining Engineering