Begell House Inc.
TsAGI Science Journal
TSAGI
1948-2590
40
6
2009
Introduction: MIKHAIL L. MIL AND TSAGI
641-644
10.1615/TsAGISciJ.v40.i6.10
Sergei Leonidovich
Chernyshev
Central Aerohydrodynamic Institute (TsAGI), 1, Zhukovsky Str., Zhukovsky,
Moscow Region, 140180, Russia
On November 22, 2009, 100 years had passed since the birth of the outstanding Russian scientist and helicopter designer M. L. Mil. During the period 1947 to 1970, first as design manager and then chief designer, Mikhail L. Mil was at the forefront in the engineering of outstanding helicopters, civil and military helicopters of the mark “Mi”. Developed by the experimental design office (EDO), these helicopters are known all over the world and are in great demand on the domestic and foreign market. More than 90% of the helicopters currently produced in Russia are the “Mi” helicopters, having the basic design laid out by M. L. Mil. In Soviet times the “Mi” helicopters exceeded the helicopters of other countries by total capacity.
M. L. Mil was closely related to TsAGI throughout his extraordinarily creative career in the pursuit of multifaceted research interests.
APPLICATION OF A NEW MATHEMATICAL TOOL (1D SPECTRAL PORTRAITS OF MATRICES) TO THE PROBLEM OF AEROELASTICITY VIBRATIONS OF TURBINE BLADE CASCADES
645-656
10.1615/TsAGISciJ.v40.i6.20
S. K.
Godunov
Sobolev Institute of Mathematics Siberian Branch of the Russian Academy of Sciences 4, Acad. Koptyug avenue, Novosibirsk, 630090, Russia
Vladimir Borisovich
Kurzin
Lavrentyev Institute of Hydrodynamics, Siberian Branch of Russian Academy of Sciences, 15 Lavrentyev pr., Novosibirsk, 630090, Russia
V. G.
Bunkov
Sobolev Institute of Mathematics Siberian Branch of the Russian Academy of Sciences 4, Acad. Koptyug avenue, Novosibirsk, 630090, Russia
M.
Sadkane
Sobolev Institute of Mathematics Siberian Branch of the Russian Academy of Sciences 4, Acad. Koptyug avenue, Novosibirsk, 630090, Russia
dichotomy quality
spectral portrait
non-symmetrical matrix
Analysis of possibilities of current conventional programs for definition of the nonsymmetrical matrix spectrum, associated with the problems of dynamic stability in aeroelasticity, was fulfilled. The feature of bending-torsion flutter of a wing with multiple oscillation frequencies near the flutter boundary was educed. The problem of flutter was studied by using the method of dichotomy.
INVESTIGATION OF THE BPR ENGINE NOZZLE WITH CONTROLLABLE CHEVRONS
657-667
10.1615/TsAGISciJ.v40.i6.30
Gennadii Nikolaevich
Lavrukhin
Central Aerohydrodynamic Institute (TsAGI), 1, Zhukovsky Str., Zhukovsky, Moscow Region, 140180, Russia
A. A.
Aleksentsev
Central Aerohydrodynamic Institute (TsAGI) 1, Zhukovsky str., Zhukovsky, 140180, Moscow region, Russia
D. B.
Bekurin
Central Aerohydrodynamic Institute (TsAGI) 1, Zhukovsky str., Zhukovsky, 140180, Moscow region, Russia
E. V.
Vlasov
Central Aerohydrodynamic Institute (TsAGI) 1, Zhukovsky str., Zhukovsky, 140180, Moscow region, Russia
A. A.
Inozemtsev
Central Aerohydrodynamic Institute (TsAGI) 1, Zhukovsky str., Zhukovsky, 140180, Moscow region, Russia
A. P.
Paduchev
Central Aerohydrodynamic Institute (TsAGI) 1, Zhukovsky str., Zhukovsky, 140180, Moscow region, Russia
O. A.
Umpeleva
Central Aerohydrodynamic Institute (TsAGI) 1, Zhukovsky str., Zhukovsky, 140180, Moscow region, Russia
3D analysis
experiment
nozzle
chevron
jet
thrust losses
engine
chevron deflection angle
optimization
noise
shape-memory materials
Results of 3D aerodynamic calculations concerning the influence of the turbojet nozzle chevron deflection angle into the flow on engine thrust characteristics are presented. The optimum deflection angle, at which the chevrons exert the minimum influence on the thrust losses, is chosen. The scheme of the deflection angle control by the ring, made of the shape-memory material nitinol is proposed. The investigation results of the aerogasdynamic and acoustic characteristics of the nozzle with the chevrons are given.
ASSYMETRY AND NONUNIQUENESS OF THE SOLUTION OF THE PROBLEM OF SEPARATED FLOW OVER A SLENDER CONICAL WING-BODY COMBINATION
669-682
10.1615/TsAGISciJ.v40.i6.40
Aleksandr Vladimirovich
Voevodin
Central Aerohydrodynamic Institute (TsAGI) 1, Zhukovsky str., Zhukovsky, 140180, Moscow region, Russia
asymmetry
non-uniqueness
separated flow
cone-delta wing
low aspect ratio
calculations with account of viscosity
Performed are the numerical investigations of the separated flow over a slender circular cone-delta wing combination within a wide range of key parameters, with the combination being situated symmetrically relative to the free stream. Two approaches are used to solve the problem. Within the framework of the slender body theory, nonunique symmetrical and asymmetrical solutions are obtained. The area of existence of various solutions is specified. The 3D-RANS CFD calculations of the small aspect ratio combination with the forebody in the form of a circular cone and with the delta wing, taking into account the viscosity, are carried out. It is shown that in this case, the problem has unique solutions, which are symmetrical at small angles of attack and asymmetrical at greater ones. At relative angles of attack, being less than 2, the lift coefficients, obtained by two approaches, are very close. This fact estimates the application area of the slender body theory. The flow patterns in the section of the combination conical part, illustrating the flow peculiarities, are given.
SUPERSONIC FLOW OVER SHARP ELLIPTICAL CONES
683-694
10.1615/TsAGISciJ.v40.i6.50
Dmitry Valentinovich
Ivanov
N. E. Zhukovskii Central Aerodynamic Institute, Zhukovskii, Moscow Region, Russia
V. V.
Pafnutiev
Central Aerohydrodynamic Institute (TsAGI) , Zhukovsky, Moscow region, Russia
Vyacheslav Antonovich
Bashkin
Central Aerohydrodynamic Institute (TsAGI), Zhukovsky, Moscow region, Russia
Ivan Vladimirovich
Egorov
Deputy Director, Aerothermodynamics, Central Aerohydrodynamic Institute (TsAGI), 1, Zhukovsky Str., Zhukovsky, Moscow Region, 140180, Russia; MIPT, 9 Institutsky pereulok, Dolgoprudny, Moscow region, Russia
elliptic cone
elliptic coefficient
angle of attack
numerical simulation
verification of the method
Completed in the present work are the calculations of supersonic viscous perfect gas flow over a set of sharp elliptical cones by means of a numerical simulation method [1,2] applied to the experiment conditions [3]. Carried out is the comparison of calculated and experimental local and integral characteristics of cones. The calculated and experimental data prove to be in a good agreement. Discussed is the influence of the angle of attack and of the cross-sectional shape on the behavior of local aerodynamic characteristics of the cone.
PECULIARITIES OF DGM APPLICATION FOR SOLUTION OF 3D EULER AND NAVIER-STOKES EQUATIONS ON UNSTRUCTURED HEXAHEDRAL GRIDS
695-718
10.1615/TsAGISciJ.v40.i6.60
Andrey Viktorovich
Wolkov
Central Aerohydrodynamic Institute (TsAGI), 1 Zhukovsky Str., Zhukovsky,
Moscow Region, 140180, Russian Federation
discontinuous Galerkin method
finite volume method
high-order scheme
A discontinuous Galerkin method (DGM) reported earlier in Refs. [1-3] has been developed for 3D Euler and Navier–Stokes equations on unstructured hexahedral grids. The algorithm enables calculations up to the fourth order and consideration of the curvature of the boundary. An ambitious approach combining the p-multigrid method and the conventional agglomeration h-multigrid method is applied as the convergence acceleration method. A variety of test cases is applied to validate the order of accuracy and to evaluate memory and central processing unit (CPU) requirements. Test cases shown in this paper cover the inviscid flow around a cylinder, the laminar flat plate, 3D flow in a bend duct, 3D turbulent flow over an isolated wing, as well as an aero-acoustic test case for the linearized Euler equations for propagation of a 3D acoustic wave. Results of calculations and CPU requirements are compared with the results obtained through the finite volume method.
INVESTIGATION OF THE APPLICATION OF ELECTRICAL DISCHARGES FOR WAVE DRAG REDUCTION
719-732
10.1615/TsAGISciJ.v40.i6.70
Vladimir Vladimirovich
Skvortsov
Central Aerohydrodynamic Institute (TsAGI) 1, Zhukovsky str., Zhukovsky, 140180, Moscow region, Russia
wave drag
electrical discharge
heat mechanism of drag reduction
ion-overheat instability
non-stationarity of flow over bodies
optical method of registration
time resolution
The problem of the main mechanism of electrical discharge influence on the wave drag of bodies at initial values of drag coefficient cx and static pressures that are of interest for aviation applications is investigated based on the experiments in classical wind tunnels with well-known and stable parameters of flows. It is shown that such a main mechanism is heat one for the types of discharges proposed for practical application. It is also shown that electrical discharges being generated in front of models can lead to unsteady supersonic flow. In turn, this stipulates essentially nonsteady flow over a body that can seem as a shock wave disappearance at insufficient time resolution of an optical method of registration.
INVESTIGATION OF THE SONIC BOOM OF THE OBLIQUE WING AIRCRAFT
733-742
10.1615/TsAGISciJ.v40.i6.80
Kyuchul
Cho
Institute of KDC
oblique wing
aerodynamic characteristics
sonic boom
The characteristics of the lift-drag ratios and sonic boom intensity of the aircraft, consisting of the oblique wing, fuselage, and vertical fin, were investigated at M∞ ∼ 1.2−1.98. The investigation results were compared to the results, obtained for the Tu-144 aircraft, having the same fuselage and fin. The Tu-144 aircraft has the same wing area as the aircraft with the oblique wing.
MOLECULAR-KINETIC DESCRIPTION OF BROWNIAN MOTION OF HEATED NONSPHERICAL PARTICLES IN HIGHLY RAREFIED GAS
743-762
10.1615/TsAGISciJ.v40.i6.90
Sergei Vladimirovich
Rusakov
Perm State University, Bukireva St. 15, 614990, Perm, Russia
Vladlen Sergeevich
Galkin
Central Aerohydrodynamic Institute (TsAGI) 1, Zhukovsky str., Zhukovsky, 140180, Moscow region, Russia
kinetic Fokker-Planck equation
nonspherical thermally nonequilibrium Brownian particles
fine-dispersed gas suspension
The kinetic equation describing translational and rotational Brownian motion of nonspherical convex solid particles in moving highly rarefied thermally inhomogeneous monatomic gas is derived. The regime of flow around the particles is free molecular, i.e., the characteristic dimensions of particles are much smaller than the average free path of the gas molecules. The interaction between the particles and their effect on the gas phase be neglected. The specular-diffuse law of interaction between the molecules and the particle surface is supposed. The temperatures of particles are equal and differ from the local gas temperature. Such a thermal nonequilibrium leads to the violation of well-known relations between the diffusion coefficients in the spaces of translational and angular velocities and the coefficients of forces and momentums acting on a particle. The coefficients in the Fokker-Planck collision operator entering into the kinetic equation are calculated for the particles in the form of the bodies of revolution. In the case of particles without longitudinal symmetry (circle cone of finite length, hemisphere etc.), the Fokker-Planck collision operator contains the second mixed derivative with respect to the translational and angular velocities.
EXPERIMENTAL STUDY OF THE JET FLOW CONTROL IN A VEHICLE AFTBODY
763-773
10.1615/TsAGISciJ.v40.i6.100
B. L.
Zhirnikov
Central Aerohydrodynamic Institute (TsAGI) 1, Zhukovskystr., Zhukovsky, 140180, Moscow region, Russia
Oleg Konstantinovich
Kudin
Central Aerohydrodynamic Institute (TsAGI), 1 Zhukovsky Str., Zhukovsky, Moscow Region, 140180, Russia
Yurii Nikolaevich
Nesterov
Central Aerohydrodynamic Institute (TsAGI), 1 Zhukovsky Str., Zhukovsky, Moscow Region, 140180, Russia
discontinuous Galerkin method
finite volume method
high-order scheme
Presented are the results of experimental investigation of the jet flow gas dynamic effect in order to control the thrust vector and to reduce the drag of the vehicle. The vehicle has a flat nozzle with an external expansion wall, being the part of the fuselage. The gas dynamic control method, based on the injection of additional air through the perforation in the expansion wall, is considered. The conclusions about the efficiency of gas dynamic control by means of various methods of additional air injection are drawn according to the weight tests and measured pressure distributions.
Index to Volume 40
775-785
10.1615/TsAGISciJ.v40.i6.110