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Aerodynamic coefficients of the HB-2 AGARD reference model measured in a new AT-303 hypersonic wind tunnel with adiabatic compression are presented. The experiments are performed in the ranges of Mach numbers

The work deals with an investigation of possibilities of controlling the aerodynamic characteristics of airfoils with the aid of external local pulsed-periodic energy supply at transonic flight regimes. The alteration of flow structure near a symmetric airfoil and its wave drag has been studied on the basis of a numerical solution of two-dimensional nonstationary gas dynamics equations versus the energy supply period, the localization and shape of the energy supply zone. The energy supply upstream of the closing shock in the immediate proximity of the contour in the zones extended along it is found to result in a considerable reduction of the profile wave drag. The nature of such a drag reduction is elucidated. The existence of a limiting frequency of energy supply is established.

The distributed (over the longitudinal coordinate) excitation of two-dimensional (2D) Tollmien

The computations of nonlinear development of pairs of oblique Tollmien ? Schlichting waves in a boundary layer on a plate are carried out for M = 2 using the non-local (parabolized) stability equations. Besides such waves, a harmonic engendered by them is involved in the interaction.

The nonlinear stage of breakdown to turbulence is a strongly three-dimensional process and represents a difficult task for experimental studies. Investigation of laminar-turbulent transition in aerospace applications additionally involves a complex base-flow with pressure gradients and secondary velocity components resulting in successive increase of necessary measurements. The developed hot-wire visualization technique offers a possibility for an advanced analysis whilst retaining the advantages of traditional visualization methods and is especially suitable for resolving such complex flows.

The inviscid supersonic flows in corners between intersecting compression wedges were studied numerically. Under usual conditions, the flows in such corner configurations are conically self-similar. Besides, shock waves formed by wedges are plane and they interact with one another in these flows and the downstream development of the shock interaction structure at that occurs in a region which is bounded in cross-sectional directions by the walls and contracts towards the corner rib, and in this sense the above interaction of shocks may be subjected to influence of the rib. The corner flows of another type with an interaction of shocks not subjected to the

The applicability of a new model in terms of the description of real gas effects in the Direct Simulation Monte Carlo method is analysed. The model is used in a numerical study of the internal structure of the front of a strong shock wave and relaxation zone behind the front for conditions corresponding to spacecraft entry into the Martian atmosphere. The influence of the free-stream parameters on relaxation of various energy modes of molecules in the wave front and in the relaxation region is considered. The effect of chemical reactions on the flow structure is studied. A detailed analysis of flow nonequilibrium is performed at the level of the velocity distribution function and population of rotational and vibrational levels of molecules.

Conjugate heat transfer was studied numerically at multisilicon production from flat-bottom crucible using a vertical version of the Bridgman

In this work, equations and methods of multiphase media mechanics were used to simulate the hydrodynamic, thermophysical, and heat- and mass-transfer processes in natural-gas flow through a horizontal pipe with allowance for gas-hydrate deposition onto the inner pipe wall. The influence of several factors on the hydrate formation process was numerically examined.

The technique for optimization of parameters of a power unit of a gas-turbine small-size heat and power plant was developed with regard for seasonable nature of heat and electric energy loads; the approach uses linear versions of dependency of outlet parameters on the inlet parameters. A mathematical model of the energy unit of a mini-HPP was developed. Optimization calculations for a coal gas-turbine mini-HPP were carried out for several optimization criteria: minimal revenue from the produced heat and electric energy (at different levels of fuel price), minimum of fuel consumption during year, and minimal investment at a given internal return rate.