An airframe integrated scramjet propelled vehicle has advantages for application to several missions. In its simplest form, such a vehicle will combine the features of quick reaction, low vulnerability to counter attack and better propulsion efficiency. The Supersonic Combustion Ramjet (SCRAMJET) engine has been recognized as the most promising air breathing propulsion system for the hypersonic...

This paper reports the simultaneous measurements of multiple flow parameters in a scramjet facility operating at a nominal Mach number of 2.5 using a sensing system based on tunable diode-laser absorption spectroscopy (TDLAS). The TDLAS system measures velocity, temperature, and water vapor partial pressure at three different locations of the scramjet: the inlet, the combustion region near the ...

This paper provides an overview of the activities associated with the aerodynamic database which is being developed in support of NASA’s Hyper-X scramjet flight experiments. Three flight tests are planned as part of the Hyper-X program. Each will utilize a small, nonrecoverable research vehicle with an airframe integrated scramjet propulsion engine. The research vehicles will be individually ro...

As one of the most promising propulsive systems in the future, the scramjet engine has drawn the attention of many researchers. The two-dimensional coupled implicit NS equations, the standard k-ε turbulence model and the finite-rate/eddy-dissipation reaction model have been applied to numerically simulate the flow field of the hydrogen fueled scramjet combustor with a cavity flameholder under t...

Scramjet unstart occurs when a strong shock initiated from disturbances in the engine propagates upstream and finally spills out of the engine inlet. When unstart occurs, the airflow into the engine is greatly diminished, leading to loss-of-thrust and engine stall. Because the probablility of unstart increases with increasing heat-release, the danger of unstart is an important limiting factor o...

With the retirement of the space shuttle near and rising fuel prices driving a demand for more efficient travel, alternative engine technology is being heavily researched. The scramjet, or supersonic combustion ramjet, has proven to be a promising development in reusable hypersonic transportation. Flight testing these engines, however, is very expensive and no scramjet flight has yet been recov...

Introduction The latest studies of the overall characteristics of hypersonic flying vehicles with airbreathing engines have shown that these vehicles are fairly promising. Some additional problems arise, however, that are related to the definition of the general shape of the aircraft, the choice of propulsion type and operation regimes, the engine size and position on the aircraft body. There h...

Recently, interest has increased in using scramjet engines as a means of long-range high-speed flights and economical access to outer space. One of the most perilous causes of scramjet malfunctions is the unstart event that is initiated by excessive heat release from combustion. When unstart occurs, a strong moving-shock structure is first formed in the engine, and the shock structure propagate...

The combination of multiplemodules in parallel manner is an important way to achieve the much higher thrust of scramjet engine. For the multiple-modules scramjet engine, when inlet unstarted oscillatory flow appears in a single-module engine due to high backpressure, how to interact with each module by massflow spillage, and whether inlet unstart occurs in other modules are important issues. Th...

NASA’s Hyper-X Research Vehicle will provide a unique opportunity to obtain data on an operational airframe integrated scramjet propulsion system at true flight conditions. The airframe integrated nature of the scramjet engine with the Hyper-X vehicle results in a strong coupling effect between the propulsion system operation and the airframe’s basic aerodynamic characteristics. Comments on gen...