Hypersonic viscous  ows near simple-shape bodies (wedge, cone, disk, and plate) have been studied numerically under the conditions of wind-tunnel experiments with underexpanded jets. The direct simulation Monte Carlo technique has been used to study the in uence of similarity parameters on the  ow structure near the bodies and on the aerodynamic coefŽ cients in hypersonic streams of air, nit...

Hypersonic chemically reacting flow around a wedge in the near-continuum regime was numerically studied by the DSMC method with the main goal of validation of real gas effect models. The influence of vibration-dissociation coupling on the results of numerical simulations was analyzed. To this end, two models of chemical reactions were used in the computations, the total collisional energy model...

This paper describes an effort to discover the highest practical flight velocity possible using air-breathing propulsion powered vehicles. The methodology includes modeling of all the key performance characteristics of a hypersonic vehicle along with a genetic algorithm based optimization study. A flexible and robust geometric modeling scheme based primarily on the use of Bernstein polynomials ...

A method for computing inviscid hypersonic ow over complex conngurations using unstructured meshes is presented. The unstructured grid solver uses an edge{based nite{volume formulation. Fluxes are computed using a ux vector splitting scheme that is capable of representing constant enthalpy solutions. Second{order accuracy in smooth ow regions is obtained by linearly reconstructing the solution,...

Rarefied gas phenomena are found in a wide variety of hypersonic flow applications, and accurate characterization of such phenomena is often desired for engineering design and analysis. In atmospheric flows involving high Mach numbers and/or low densities, underlying assumptions in a continuum fluid dynamics description tend to break down, and distributions of both molecule velocity and interna...

We investigate the coherent bremsstrahlung by relativistic electrons in a single crystal excited by hypersonic vibrations. The formula for the corresponding differential cross-section is derived in the case of a sinusoidal wave. The conditions are specified under which the influence of the hypersound is essential. The case is considered in detail when the electron enters into the crystal at sma...

The interval type-2 fuzzy, combined with sliding mode control, is proposed in this paper to design a novel nonlinear robust controller for a hypersonic aircraft. In this method, sliding mode reaching law is designed to keep the system stable. In order to overcome the uncertain parameters and external disturbances which exist in aerospace, we utilize an interval type-2 fuzzy approach represented...

Within this paper, control-relevant vehicle design concepts are examined using a widely used 3 DOF (plus flexibility) nonlinear model for the longitudinal dynamics of a generic carrot-shaped scramjet powered hypersonic vehicle. The impact of elevator size and placement on control-relevant static properties (e.g. level-flight trimmable region, trim controls, AOA, thrust margin) and dynamic prope...

A second-mode stability analysis has been performed for a hypersonic boundary layer on a wall covered by a porous coating with equally spaced cylindrical blind microholes. Massive reduction of the second mode ampliŽ cation is found to be due to the disturbance energy absorption by the porous layer. This stabilization effect was demonstrated by experiments recently conducted on a sharp cone in t...