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1.
A. P. Kuryachii 《Fluid Dynamics》1998,33(6):876-881
A solution of the coupled nonstationary boundary-value problem of turbulent flow around a flat heat-conducting plate of finite
thickness having local regions with volume heat sources is given. For modeling the heat transfer in the boundary layer, thek-ε turbulence model is used. It is shown that the thermal conductivity of the plate material significantly affects the surface
distributions of both temperature and local friction.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 6, pp. 79–86, November–December,
1998.
The work received financial support from the International Scientific and Engineering Center (project No.199). 相似文献
2.
V. M. Agranat 《Fluid Dynamics》1988,23(5):729-732
Approximate analytic expressions for the local friction and heat transfer coefficients in a dusty laminar boundary layer are
obtained and tested in the case of an incompressible carrier phase, power-law variation of the external gas flow velocity
and small velocity and temperature phase disequilibrium. These expressions supplement the numerical analysis of the dusty
boundary layer on a blunt body [1, 2] and the asymptotic calculation of the friction and heat transfer in a quasiequilibrium
dusty gas boundary layer on a plate [3]. The combined effect of dustiness and pressure gradient on the friction and heat transfer
coefficients is discussed. The results obtained can be used for the practical calculation of the friction and heat transfer
in a quasiequilibrium dusty laminar boundary layer and for interpreting the corresponding experimental data.
Tomsk. Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 105–108, September–October, 1988. 相似文献
3.
V. A. Levin V. G. Gromov N. E. Afonina 《Journal of Applied Mechanics and Technical Physics》2000,41(5):915-922
The effect of local source of energy in a supersonic flow on the aerodynamic drag and heat transfer of a spherically blunted
body is studied numerically. Calculations are performed on the basis of the Navier-Stokes equations for a thermally equilibrium
model of air. Data on the effect of the intensity and size of the energy source on the wave drag, friction, and heat transfer
are obtained. Particular attention is given to studying the effect of drag reduction by means of a focused heat source. The
gas-dynamic nature of this effect is studied. The limits of drag reduction are estimated, and optimal conditions of heat supply
are determined.
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 5, pp. 171–179, September–October, 2000. 相似文献
4.
Reducing frction drag and delaying the laminar-turbulent transition are topical problems of modern aerodynamics. A series of methods of delaying transition are known: creation of a favorable pressure gradient, boundary layer suction, surface cooling, etc., [1, 2]. Here, the possibility of delaying transition by means of volume heat supply to the boundary layer is considered. For this purpose, a subsonic compressible laminar boundary layer with volume energy supply is subjected to a stability analysis. The nonself-similar flow in the boundary layer is determined by means of a finite-difference marching method. The flow stability characteristics are calculated on the basis of the linear theory in the plane-parallel approximation. It is shown that even on a thermally insulated surface volume energy supply to the flow leads to significant flow stabilization and reduced perturbation growth rates.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 62–67, March–April, 1988. 相似文献
5.
A subsonic stream of gas flowing over a thermally insulated plate and having an elevated temperature in a thin layer adjacent
to the surface is considered. This temperature distribution in the flow can be obtained by providing a volume energy supply
near the leading edge of the plate. The results of calculating the position of the line of laminar-turbulent transition on
the basis of linear stability theory and the eN method are presented. It is shown that the presence of a heated layer of gas near the surface of the plate leads to an increase
in the stability of the laminar flow and an extension of the laminar interval of the boundary layer. A nonmonotonic dependence
of the length of the laminar interval on the thickness of the heated layer of gas is detected.
Moscow. Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 58–61, September–October, 1988. 相似文献
6.
Numerical simulations of unsteady radiative-convective heat transfer in a turbulent flow of a mixture of gases and solid particles
past a semi-transparent plate are performed. An ablation process is demonstrated to occur on the plate surface in the case
of intense radiative heating of the plate by an external source with emission in a limited spectral range. Temperature fields
and distributions of heat fluxes in the boundary layer and in the plate are calculated. Calculation results are presented,
which allow determining the effect of ablation and reflecting properties of the plate surface on the thermal state of the
medium in the system containing the boundary layer and the plate under conditions of plate heating by a high-temperature source
of radiation.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 50, No. 3, pp. 140–146, May–June, 2009. 相似文献
7.
The steady laminar boundary layer flow and heat transfer from a warm, laminar liquid flow to a melting surface moving parallel
to a constant free stream is studied in this paper. The continuity, momentum and energy equations, which are coupled nonlinear
partial differential equations are reduced to a set of two nonlinear ordinary differential equations, before being solved
numerically using the Runge–Kutta–Fehlberg method. Results for the skin friction coefficient, local Nusselt number, velocity
profiles as well as temperature profiles are presented for different values of the governing parameters. Effects of the melting
parameter, moving parameter and Prandtl number on the flow and heat transfer characteristics are thoroughly examined. It is
found that the problem admits dual solutions. 相似文献
8.
V. M. Agranat 《Fluid Dynamics》1986,21(6):983-985
The nonisothermal Blasius problem for a gas suspension is considered on the basis of the equations of a quasiequilibrium two-phase
laminar boundary layer [1–3]. Approximate analytical expressions are obtained for the friction and heat transfer coefficients
and their region of applicability is estimated; the Reynolds analogy between friction and convective heat transfer processes
[4] is extended to the case of a dusty quasiequilibrium laminar boundary layer.
Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 6, pp. 160–162, November–December, 1986. 相似文献
9.
In this paper, the problem of free convection boundary layer flow on a solid sphere in a micropolar fluid with Newtonian heating,
in which the heat transfer from the surface is proportional to the local surface temperature, is considered. The transformed
boundary layer equations in the form of partial differential equations are solved numerically using an implicit finite-difference
scheme. Numerical solutions are obtained for the local wall temperature, the local skin friction coefficient, as well as the
velocity, angular velocity and temperature profiles. The features of the flow and heat transfer characteristics for different
values of the material or micropolar parameter K, the Prandtl number Pr and the conjugate parameter γ are analyzed and discussed. 相似文献
10.
E. A. Ryabitskii 《Fluid Dynamics》2000,35(3):315-320
The effect of thermodiffusion on the onset of thermocapillary instability in the presence of a surfactant is investigated
with reference to a plane liquid layer. It is shown that taking the Soret effect into account leads to destabilization in
the case of heating of both the rigid surface and the free boundary.
Krasnoyarsk. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 3, pp. 3–9, May–June, 2000. 相似文献
11.
A. P. Kuryachii 《Fluid Dynamics》1998,33(1):48-55
The results of calculating a supersonic turbulent boundary layer on a heated surface on the basis of the algebraic two-parameter
(k-ε) and four-parameter (k-ε-θ
2-ε
6) models of turbulence are compared with experimental data. Emphasis is placed on the ability of the models to predict the
behavior of the friction and heat-transfer coefficients on a heated surface. The optimal model of turbulence is chosen. The
possibility of improving the efficiency of viscous drag reduction by localizing the regions of heat addition to the boundary
layer is demonstrated on the basis of numerical calculations.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 59–68, January–February,
1998.
This research was carried out with financial support from the International Scientific and Technological Center (project No.
199). 相似文献
12.
Heat transfer from a thin filament pulled from a half-space is considered. On the basis of the self-similar solution, obtained
in the study, and using the method of effective length, the friction and heat transfer coefficients on the surface of a thin
filament of varying radius and with distributed surface temperature and velocity are determined. The results obtained with
this approximate method agree well with the results of a numerical solution of the boundary layer equations.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 23–28, January–February,
1994. 相似文献
13.
The problem of the convective instability of a plane fluid layer bounded by rigid walls with heating in a narrow layer running
parallel to the walls inside the volume in question is solved. Instability criteria depending on the location of the heated
layer and the Rayleigh numbers of the upper and lower layers are found. The results are compared with those for a plane layer
with uniform energy release inside the volume.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 8–15, January–February,
1997.
The work was carried out with partial support from the Russian Foundation for Fundamental Research (project No. 95-01-00354a). 相似文献
14.
Vik V. Sychev 《Fluid Dynamics》1998,33(6):882-890
This paper studies the effect of two-dimensional surface irregularities on the flow in a plane steady boundary layer with
small skin friction in an incompressible fluid. A detailed analysis is carried out for the flow regime with a given pressure
gradient determined on the scale of the small irregularity by its shape. It is shown that there is a critical value of the
height (depth) of the irregularity at which the skin friction first becomes zero, and the nonuniqueness of the corresponding
solution is established.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 6, pp. 87–97, November–December,
1998.
The work was financially supported by the Russian Foundation for Basic Research (project No. 97-01-00354). 相似文献
15.
The results of an experimental investigation of the mechanism of reducing surface friction by mounting thin plates — large-eddy break-up devices (LEBUs) — in a turbulent boundary layer parallel to the surface are given. The conditions under which the surface friction reduction is minimal are determined. It is shown that the presence of LEBUs in the turbulent boundary layer leads to a decrease in the frequency of decelerated-fluid ejection from the wall region into the outer region of the boundary layer.Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 5, pp. 80–89, September–October, 1996. 相似文献
16.
For verifying the method of calculating the boundary layer in liquid rocket engine (LRE) nozzles developed by the authors
on the basis of a differential three-parameter turbulence model, the boundary layer on a plate in a zero-gradient flow is
calculated. Over a wide range of variation of the free-stream Mach number, the temperature factor, and the Reynolds number,
based on the momentum thickness of the boundary layer, the calculation agrees satisfactorily with the known experimental data,
with respect to both integral and local flow and heat transfer characteristics.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 6, pp. 64–78, November–December,
1998.
The work received financial support from the Russian Foundation for Basic Research (project No.96-012-00260). 相似文献
17.
The effects of viscous dissipation on unsteady free convection from an isothermal vertical flat plate in a fluid saturated
porous medium are examined numerically. The Darcy–Brinkman–Forchheimer model is employed to describe the flow field. A new
model of viscous dissipation is used for the Darcy–Brinkman–Forchheimer model of porous media. The simultaneous development
of the momentum and thermal boundary layers are obtained by using a finite difference method. Boundary layer and Boussinesq
approximation have been incorporated. Numerical calculations are carried out for various parameters entering into the problem.
Velocity and temperature profiles as well as local friction factor and local Nusselt number are shown graphically. It is found
that as time approaches infinity, the values of friction factor and heat transfer coefficient approach steady state. 相似文献
18.
An analytical solution to the problem of condensation by natural convection over a thin porous substrate attached to a cooled
impermeable surface has been conducted to determine the velocity and temperature profiles within the porous layer, the dimensionless
thickness film and the local Nusselt number. In the porous region, the Darcy–Brinkman–Forchheimer (DBF) model describes the
flow and the thermal dispersion is taken into account in the energy equation. The classical boundary layer equations without
inertia and enthalpyterms are used in the condensate region. It is found that due to the thermal dispersion effect, the increasing
of heat transfer is significant. The comparison of the DBF model and the Darcy–Brinkman (DB) one is carried out. 相似文献
19.
N. A. Rubtsov S. D. Sleptsov N. A. Savvinova 《Journal of Applied Mechanics and Technical Physics》2006,47(3):377-383
Numerical modeling of the single-phase Stefan problem in a semitransparent layer with transparent, nonabsorbing, and partially
radiation-absorbing boundaries is performed. It is shown that at low temperatures of the medium, convection is a determining
factor on the boundary of the irradiated sample, and at high temperatures, radiation is predominant. The absence of absorption
on the boundaries of the layer leads to acceleration of the heating of the plate and considerable deceleration of melting
processes.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 3, pp. 84–91, May–June, 2006. 相似文献
20.
The characteristics of the flow and heat transfer in two- and three-dimensional open cavities on plane and cylindrical surfaces
in a supersonic stream in the presence of a turbulent boundary layer have been investigated experimentally. The effects of
the Mach number, boundary layer thickness, the shape of the cavity, and its angle of inclination to the free-stream direction
on the flow parameters in the mixing layer above the cavity and the heat flux and pressure distribution on the surface of
the cavity and its bottom are descirbed.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 4, pp. 74–80, July–August, 1998. 相似文献