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The requirements for hypersonic air data measurement are reviewed, and techniques for the measurement of air data parameters for hypersonic vehicles are presented and assessed. Today's hypersonic vehicles, primarily the space shuttle, have had restricted flight envelopes and required minimal air data measurement performance. ...Advanced hypersonic vehicles are now being designed that will greatly expand the envelope of hypersonic travel. ...Accurate measurement or derivation of vehicle altitude, rates, Mach number, angle of attack, and sideslip are required to ensure that operation of a hypersonic vehicle over a broader envelope is possible. The hypersonic vehicle must operate in an environment characterized by low atmospheric and high dynamic pressures combined with high external-surface temperatures that reach extremes higher than 2000°C with flow velocities approaching Mach 25.

Numerical simulations of hypersonic flow around a 2-D cylinder and a 3-D complete reentry vehicle have been carried out by solving Euler/Navier-Stokes equations which incorporate the equation of state for an equilibrium gas. ...The results of hypersonic flow analysis using this code suggest us that the real gas effects, such as chemical reaction, are not negligible to predict the hypersonic flow characterisics acculately. ...The results of hypersonic flow analysis using this code suggest us that the real gas effects, such as chemical reaction, are not negligible to predict the hypersonic flow characterisics acculately.

Hypersonic Aerodynamics has attracted outstanding graduate students and faculty at NCSU. It has grown to 6 faculty and 32 graduate students for fall, 1988. ...The combined program produces graduates with the background needed to perform aerodynamics investigations of hypersonic aircraft and spacecraft. The research performed helps advance the state of the art as well as assist government laboratories in meeting their goals.

A transversely injected jet into a hypersonic flow is simulated numerically in order to study the flow field of the injection jet in the hypersonic atmosphere, its heat flux on the body surface and the moments working on the body. ...A transversely injected jet into a hypersonic flow is simulated numerically in order to study the flow field of the injection jet in the hypersonic atmosphere, its heat flux on the body surface and the moments working on the body. The flowfields is governed by the two-dimentional Reynolds averaged full Navier-Stokes equations with an algebraic eddy viscosity model developed by Baldwin-Lomax.

Thermal protection systems (TPS) for hypersonic transport vehicles are described and evaluated. During the flight through the atmosphere moderate to high aerodynamic heating rates with corresponding high surface temperatures are generated. ...It is demonstrated that microporous and multiwall insulations are efficient, light weight and reliable TPSs for future hypersonic transportation systems.

This paper presents the theory of an insulation-radiation cooling method applicable to expandable hypersonic vehicles; two simple configurations, a sphere and a cylinder, are analyzed to illustrate this method.

The development of simulation codes for hypersonic flow computations is the pacing ilea in the definition of a reentry vehicule such as the European HERMES, in order to complement the experimental facilities which cannot cover the complete flight envelope.

A single, efficient, reliable emergency escape system is needed to provide, at an acceptable total cost, emergency escape capability throughout the entire mission envelope of hypersonic and orbital vehicles. Analysis and limited testing indicate that the Douglas Paracone emergency escape system will meet this requirement.

The refractories were being considered for the wing leading edges and the nose of a proposed hypersonic aircraft. The insulants were for application between the outer skins and the interior structure.*

However, the impact of disciplinary, operational, and technological uncertainties inhibit the design of the requisite hypersonic vehicles, an inherently multidisciplinary and non-deterministic process. Without investigation, these components of design uncertainty undermine the designers’ decision-making confidence.

Hypersonic flight vehicles, capable of flight in excess of five times the speed of sound, can be categorized into two basic types: blunt, high drag shapes, and sharp, low drag forms. ...Though the majority of hypersonic flight experience is invested in blunt geometries for spacecraft reentry, sharp high-speed aerodynamic shaped can be applied to a wide range of missions, including missiles, cruisers, accelerators, and maneuvering space vehicles. ...Several upcoming programs, most notably the NASA Ames SHARP flight tests, will demonstrate some of the key aerodynamic and materials technologies that will enable the practical development of high-lift, low drag hypersonic vehicles. The NASA Glenn Trailblazer vehicle is also described as an opportunity to apply these technologies on a promising access-to-space vehicle.

Hypersonic flows over simple 3-D bodies and a space vehicle are simulated using a real-gas Navier- Stokes code under an equilibrium air assumption.

Hypersonic flight vehicles have potential applications in strategic defence, space missions, and future civilian high-speed transportation systems. ...Scramjet-powered air-breathing hypersonic vehicles experience extreme heat loads induced by combustion, shock waves and viscous heat dissipation.

Actual research activities are focused on the development of advanced HVOF sprayed coating systems on cylinder liners, the coating optimization and the cost effective implementation of this technology in an automated series production process. In hypersonic flame spraying (HVOF), the coating is deposited by an elliptically moving HVOF gun, whereas the cylinder liner is rotating.

Actual trends with regard to light weight design in the automotive industry, in order to reduce fuel consumption and pollution emissions as well as improve the engine efficiency lead to the increasing use of light weight engine components. Due to the harsh operation conditions, the aluminum cylinder surface must be reinforced, and new techniques have been developed and applied. A very promising technological alternative is the use of HVOF (high velocity oxygen fuel) deposited internal coatings, showing improved coating quality results compared to APS (atmospheric plasma spray) coatings. Several HVOF (High Velocity Oxygen Fuels) coating processes (with different fuel gases/fluids) were compared and studied, with a complete mechanical characterization and evaluation of the coatings. Also an economical comparison for the different coating systems is shown.

Despite recent advancements in the physics and chemistry of high temperature air flows, large uncertainties remain to be reduced. Numerical procedures are necessary for advancement of understanding and modeling of their effects. Unfortunately, they have complex effects on the complex shapes of orbiter like U.S. Shuttle Orbiter and Hermes, and on the flight-test results, where they are mixed together with other complex phenomena, related to viscous flows. For clarification of the engineering implication of modeling uncertainties, some results of comparisons are given for different physical and chemical modeling on the simple shape of an AOTV. They emphasize the effect on the pitching moment and on the heat transfer, and give correlated variations in the bow shock wave, conclusions are given on the research to be pushed, and its inclusion in the Hermes aerothermal research program, presently in progress amongst the European scientific community.

The team completed a successful baseline design review that establishes the technical approach for a critical design review, which moves the system a step closer to development and use.

The results of computational investigations carried out to clarify the possibilities of hydrogen scramjet thrust uprating in hypersonic flight (Mf>8) by adding to the fuel substances with higher density are presented. Thrust, specific impulse and density impulse are calculated while adding nitrogen, oxygen, water or inert liquated gases. ...For scramjet boosting in hypersonic flight it is suggested to add oxygen or a heavy inert gas to stoichiometric part of hydrogen instead of excessive part of hydrogen.

The first reviews some implications of hypersonic performance with special emphasis on return of logistics spacecraft from orbit to the continental U.S. ...The second part of the paper surveys representative vehicle concepts ranging from low to high hypersonic lift-drag ratios. Particular attention is centered on landing modes and their implications.

A major use of these new materials is in the structural parts for hypersonic aircraft.