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2006 year, number 3
N.P. Adamov1, M.D. Brodetsky1, L.G. Vasenev1, V.I. Zvegintsev1, I.I. Mazhul1, A.M. Kharitonov1, J.-C. Paulat2, J. Muylaert3, and W. Kordulla3
1Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia 2European Aeronautic Defence and Space Company Space Transportation (EADS-ST), Les Mureaux, France 3European Space Research and Technology Center (
Pages: 317-326
Abstract >>
Results of an experimental study of aerodynamic characteristics of models of two hypersonic re-entry vehicles (ARES-H aerospace demonstrator proposed by EADS-ST and EXPERT re-entry capsule proposed by ESA ESTEC) are presented. The experiments were performed in a new wind tunnel AT-303 at ITAM SB RAS in the range of free-stream Mach numbers
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S.G. Mironov and I.S. Tsyryul'nikov
Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia
Pages: 327-333
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Characteristics of the fields of mean density and density fluctuations measured with introduction of periodic disturbances into a hypersonic viscous boundary layer on a flat plate are presented. The experiments are performed for a flow Mach number M∞ = 21, Reynolds number per meter Re1∞ = 6·105 m-1, and temperature factor of the surface Tw /T0 = 0.26. The disturbances are introduced into the shock layer by an oblique gas-dynamic whistle.
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V.I. Terekhov, N.I. Yarygina, and Ya.I. Smul'sky
Kutateladze Institute of Thermophysics SB RAS, Novosibirsk, Russia
Pages: 335-341
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Results of an experimental hydrodynamic and heat-transfer study of the turbulent separated flow developing over a system of several cross-flow ribs are reported. Conditions with low and high free-stream turbulence are considered. Visualization and heat-transfer data are presented, and a comparison for two turbulence levels is given. In the system of three or more ribs, a very unstable flow in the second inter-rib cell was observed under low-turbulence conditions. Under a high level of free-stream turbulence, the flow in the first inter-rib cell is unstable; this observation is supported by measured pressure distributions. Addition of each next rib makes the separation flow region behind the last rib and the pressure recovery region less extended, and decreases the coordinate at which the rate of heat transfer attains its maximum. In the high-turbulent flow, the heat-transfer intensification in the second inter-rib cell amounts to 30 %.
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V.I. Kornilov
Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia
Pages: 343-357
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The effect of periodic blowing/suction on characteristics of a turbulent boundary layer formed on an axisymmetric body of revolution in a nominally gradientless incompressible flow is studied experimentally. The Reynolds number based on the momentum thickness at the location of an annular slot for blowing/suction is 1176. The dimensionless slot width in the wall units is 68. It is demonstrated that blowing/suction aimed at controlling the boundary-layer flow is a fairly effective method for controlling the near-wall turbulence structure and ensures a certain gain in friction drag over the initial configuration (the maximum gain reaches 25 30 %).
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S.V. Klinkov, V.F. Kosarev, and A.A. Sova
Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia
Pages: 359-368
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An ejector scheme intended for forming supersonic heterogeneous flows is experimentally examined as applied to conditions typical of cold gas-dynamic spraying. Pressure and temperature distributions in the supersonic part of the nozzle are reported, and critical operating regimes of the nozzle are identified. Specific features and advantages demonstrated by this scheme in practical applications are considered. Results of preliminary tests on the application of coatings with the use of the nozzle unit under study are presented.
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E.N. Vasil'iev, V.A. Derevyanko, and D.A. Nesterov
Institute of Computional Modelling SB RAS, Krasnoyarsk, Russia
Pages: 369-
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A computational model for processes in the duct of an experimental setup consisting of a shock tube and an MHD duct is presented. The one-dimensional model is used for determining the flow characteristics in the entire setup duct, and the three-dimensional model is used for studying the current layer dynamics in the MHD channel. Computations have enabled the elucidation of flow structure and of the peculiarities of current layer formation.
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O.N. Kashinsky, A.S. Kurdyumov, and V.V. Randin
Kutateladze Institute of Thermophysics SB RAS, Novosibirsk, Russia
Pages: 381-385
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This paper deals with wall shear stress in an upward gas-liquid slug flow inside a vertical tube. Local characteristics were measured by the electrodiffusion method. The method of conditional averaging over realization ensemble was used, and this allows distinguishing large-scale structures on the background of turbulent pulsation of liquid. While averaging, each slug velocity measured by a double probe of electric conductivity was taken into account. Averaged distributions of shear stress over the wall under a gas slug were obtained for different mode parameters.
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L.I. Maltsev, A.G. Malyuga, and B.G. Novikov
Kutateladze Institute of Thermophysics SB RAS, Novosibirsk, Russia
Pages: 387-392
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Two different mechanisms responsible for the were revealed impact of gas bubbl injected into a boundary layer on the shear stress on the wetted surfaces. Both mechanisms exist due to extremely high sensitivity of bubbles even to very low pressure gradients and due to a high value of the virtual mass and coefficient of viscous drag for bubbles. The first mechanism manifests itself at the interaction of vortex structures with bubbles in the near-wall layer y+ < 250. The second mechanism is due to pressure gradient along the wetted surface. Ascertainment of these mechanisms explains the known discrepancies in the experimental results on gas saturation obtained on different experimental setups.
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I.V. Kostolomov and A.G. Kutushev
Tyumen State University of Civil Engineering, Tyumen, Russia
Pages: 393-401
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Mathematical modelling of three-dimensional steady free convective incompressible viscous gas flows in the rooms with a heat source is carried out within the framework of the Navier Stokes equations with the effective viscosity determined on the basis of the κ-ε turbulence model. The investigation is carried out for the case of model rooms and heat sources having the form of rectangular parallelepipeds with square bases. The influence of the heat source power and the sizes of the room base on local and averaged values of the air velocity and temperature in the rooms is analysed. The flow pattern in the room is shown to have a torus-like shape. It is found that the variation of sizes of the room base rather than the capacity variation of the heat source is of determining importance for the gas motion character in a closed volume.
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I.V. Mezentsev1, N.V. Vernikovskaya2, Yu.I. Aristov2, and V.A. Mukhin3
1Kutateladze Institute of Thermophysics SB RAS, Novosibirsk, Russia 2Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia 3Siberian State University of Transport, Novosibirsk, Russia
Pages: 403-410
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Experimental results on reversing non-stationary heat transfer are presented for filtration of an air flow through an immobile heat accumulating medium consisting of lead (D = 2.0, 3.5, and 4.5 mm) and glass (D = 3.2 mm) balls. The studied device imitated the cyclic modes of heat regeneration in the ventilation system for domestic and office rooms. Dependency between the time of flow switching and Re number was measured. The mathematical model describing heat transfer between a gas flow and an immobile layer of balls was developed. Good correspondence between the experimental data and calculation results is observed for high Reynolds numbers. For low Re numbers the effect of heat losses is considerable, and experimental time of flow switching is shorter than the calculation one.
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V.A. Gruzdev and S.G. Komarov
Kutateladze Institute of Thermophysics SB RAS, Novosibirsk, Russia
Pages: 411-418
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The saturation pressure, pressure and density of superheated vapor of 1,1,1,2,3,3-hexafluoropropane (HFC-236ea, R-236ea) were studied by an isochoric piezometer within the temperature range of 294-423 K up to the pressure of 4.0 MPa. The uncertainties of temperature, pressure, and density measurements were estimated as ±20 mK, ±1.5 kPa, ± (0.1-0.2) %, and ± (0.1-0.2) %, correspondingly. The purity of studied samples was 99.68 mass %. The obtained experimental data are shown as tables and analytical equations. Coefficients of the virial state equation were calculated for R-236ea on the basis of these data.
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A.N. Cherepanov1, V.N. Popov1, A.E. Detsel2, A.B. Aleksandrov2, and A.I. Drobyaz2
1Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia 2Open Joint-Stock Company The Novosibirsk Plant of Chemical Concentrates, Novosibirsk, Russia
Pages: 419-425
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A two-dimensional mathematical model has been developed for unsteady thermophysical processes in the industrial duct of an uranium-graphite reactor with conversion fuel elements of the bush type. The numerical algorithm and computer code have been developed on the basis of the proposed model to investigate the temperature fields in an aluminum core, fuel, shell as well as in the cooling water with regard for the design and technological assembly peculiarities. The results of some computational experiments are presented, which characterize the distribution of temperature fields in the column of fuel elements and in the cooling water.
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S.P. Rusin
Institute for High Energy Densities of Association Institute for High Temperatures of RAS, Moscow, Russia
Pages: 427-434
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The zonal-iterative calculation method for radiation heat transfer is developed for arbitrary number of zones (opaque diffusely-radiating and reflecting surfaces). This method is based on transformation of the initial integral equations to equivalent system of integral equations with smaller kernel norm. The method provides high accuracy at a small number of the zones. The method was used for analysis of effective radiation in an isothermal tube cavity with a longitudinal pyrometric slit. In this case one zone was enough and one of the particular solutions can be obtained analytically.
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V.A. Shveygert and I.V. Shveygert
Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia
Pages: 435-444
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A new combined numerical algorithm PIC-MCC (the particle-in-cell method with the collisions modelling by the Monte Carlo method) has been developed for a rapid computation of a radio-frequency (RF) discharge under a low pressure and a high plasma concentration. The results of test computations for various regimes of the capacitive RF discharge glow in argon and helium well agree with experimental data. A high efficiency of the new approach (the combined PIC-MCC algorithm) is demonstrated for modelling the electrons heating in the collisionless regime.
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B. I. Mikhailov
Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia
Pages: 445-454
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The possibility of separation of the water-steam plasma in a centrifugal force field of a vortex stream is under consideration. We obtained the formulas to compute the radial distribution of the plasma mixture components and also to determine the dependence of the pressure and its gradient on the distance to the axis for the regions of solid-state and potential rotation of the vortex. The examples of poor arc stabilization and the proposals for its perfection are presented. The effect of the gas kind on the voltage of the vortex-stabilized arc is shown. The influence of the water-steam plasma individual components, regarding the separation, on the water-steam plasma energy characteristics is explained.
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A.S. An'shakov1, E.K. Urbakh1, A.E. Urbakh1, V.A. Faleev1, M.V. Cherednichenko2, and M.A. Shelest2
1Kutateladze Institute of Thermophysics SB RAS, Novosibirsk, Russia 2Novosibirsk State Technical University, Novosibirsk, Russia
Pages: 455-461
Abstract >>
Electric and thermal characteristics of the two-chamber plasmatorch with a stepped outlet electrode were studied experimentally. Formulas for determination of arc voltage, plasmatorch efficiency, and length of a narrow part of the outlet electrode were derived. It is shown that such a plasmatorch is more efficient than the plasmatorch with a smooth outlet electrode.
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