共查询到20条相似文献,搜索用时 31 毫秒
1.
A. V. Lokotko 《Journal of Applied Mechanics and Technical Physics》1999,40(6):1061-1069
A method of experimental determination of the force characteristics of nozzles (thrust, lift, and pitching moment) simultaneously
with the aerodynamic characteristics of an aircraft model in a supersonic flow in proposed. The tests were conducted for a
special methodical model, with equilibrium of the thrust and drag jorces being reached. It is shown that the internal force
characteristics of the nozzle and the drag of the model, as well as the effective lift and pitching moment (with account of
propulsion), can be determined from the measured thrust of the propulsion simulator.
Institute of Theoretical and Applied Mechanics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated
from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 40, No. 6, pp. 73–82, November–December, 1999. 相似文献
2.
A. N. Varyukhin 《Journal of Applied Mechanics and Technical Physics》2008,49(5):770-775
A method is proposed for calculating small deformations of the boundaries of an axisymmetric cavity with impinging gas jets.
No constraints are imposed on the configuration and characteristics of the system of nozzles generating the jets. Numerical
results are compared with data obtained by available semi-empirical methods and with experimental data.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 5, pp. 80–86, September–October, 2008. 相似文献
3.
A. K. Kuzin 《Fluid Dynamics》2000,35(3):331-338
The problem of the equilibrium shape of a steady rotating rectilinear infinite cord of ideal self-gravitating homogeneous
fluid is considered. The question whether, apart from the obvious solution, namely, an infinite circular cylinder, noncylindrical
equilibrium figures can exist is investigated. A search is carried out among axisymmetric figures with periodic surface structure
(“wavy” cylinders). The period of the wave structure and, in the first approximation, the shape of the surface are found as
functions of the angular velocity of rotation.
Sankt-Peterburg. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 3, pp. 22–30, May–June,
2000. 相似文献
4.
An analytical solution is developed for conjugate heat transfer in a flat-plate heat exchanger with circular embedded channels.
The analysis was carried out for fully-developed conditions in the circular tube and uniform heat flux at the plate boundary.
The results are applicable to cooling channels that are 50 μm or more in diameter with a large length–diameter ratio. The
thermal characteristics of the heat exchanger have been examined for a wide range of the relevant independent parameters and
optimum designs for three different sets of constraints have been presented. It was found that the overall thermal resistance
increases with the depth of the tube from the heated surface, as well as the spacing between the tubes. For a given combination
of tubes’ depth and spacing, there is a certain tube diameter at which the thermal resistance attains a minimum value. 相似文献
5.
V. I. Grabovskii 《Fluid Dynamics》2000,35(4):525-533
The optimum design of a gas hydrostatic thrust bearing clearance is obtained using the methods of calculus of variations.
The variational problem of determining the clearance shape giving the maximum load capacity is solved for a given external
pressurization and various journal speeds. The structure of the optimum solution is found on the basis of the gas lubrication
approximation with and without constraints on the height of the bearing pad (pocket). The calculation results embrace all
possible values of the parameters. A comparison with optimum liquid bearings is carried out.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 4, pp. 68–78, July–August, 2000.
The work was carried out with support from the Russian Foundation for Basic Research (projects Nos. 99-01-01211 and 96-15-96158). 相似文献
6.
S. M. Aulchenko V. M. Galkin V. I. Zvegintsev A. N. Shiplyuk 《Journal of Applied Mechanics and Technical Physics》2010,51(2):218-225
A method for design of hypersonic nozzles for wind tunnels is developed and implemented on the basis of solving direct problems
with various models of the medium and numerical methods of integration of gas-flow equations. Multimodal nozzles for operation
in Mach number ranges M
out
=8–14 and M
out
=14–20 satisfying specified requirements are designed. 相似文献
7.
Mixing of high speed coaxial jets 总被引:3,自引:0,他引:3
R. I. Sujith R. Ramesh S. Pradeep S. Sriram T. M. Muruganandam 《Experiments in fluids》2001,30(3):339-345
In this study, five different supersonic nozzles – conical, elliptical, tabbed, radially lobed and two-dimensional lobed
– are compared experimentally for their mixing performance. With the background of studies by various groups conducted on
the above nozzles, the present paper aims to provide an experimental comparison of their respective mixing performances with
that of a conventional conical nozzle under identical operating conditions. The mixing of the supersonic stream coming from
such nozzles with a coaxial sonic stream is investigated. The investigation is performed non-intrusively, using digital image
processing of planar Mie-scattering images of the flow field. The results of these investigations reveal the superiority of
mixing performance of the two-dimensional lobed nozzle over conventional circular and other non-conventional nozzles.
Received: 15 July 1999/Accepted: 3 July 2000 相似文献
8.
A. G. Kuz’min 《Journal of Applied Mechanics and Technical Physics》2008,49(6):919-925
A turbulent flow past two symmetric airfoils, whose bow and aft portions are circular arcs, whereas midparts are flat, is
studies numerically. The amplitude of lift coefficient oscillations versus the free-stream Mach number M
∞
is analyzed at zero angle of attack. Ranges of M
∞
in which there exist flow bifurcations are determined.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 6, pp. 37–44, November–December, 2008 相似文献
9.
In this study four different supersonic nozzles – circular, elliptical, tabbed, and radially lobed nozzles are compared experimentally
for their freejet mixing performance. With the background of studies by various groups conducted on elliptical, tabbed, and
radially lobed nozzles, the present paper aims at a comparative experimental study to compare their mixing performance with
that of a conventional circular nozzle under identical operating conditions. The investigation is performed non-intrusively,
using digital image processing of the planar Mie scattering images of the flow field. The results of these investigations
reveal the superiority of the mixing performance of the lobed nozzles over conventional circular and other non-conventional
nozzles.
Received: 29 July 1998/Accepted: 5 November 1999 相似文献
10.
Supersonic perfect gas flow in plane and axisymmetric channels with the same duct contour is studied on the basis of a numerical
solution of the two-dimensional Navier-Stokes and Euler equations. The calculations were carried out at an inlet Mach number
M∞=4 for various Reynolds numbers and “bell-mouth“ half-angles. The effect of these parameters, as well as that of the flow
three-dimensionality, on the flow pattern is demonstrated. In particular, the existence of viscous flow regimes providing
the most effective supersonic flow deceleration and a higher degree of total pressure recovery as compared with the inviscid
flow is established.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 2, pp. 143–152, March–April, 1998.
The study was carried out with the support of the Russian Foundation for Fundamental Research (project No. 95-01-01129a). 相似文献
11.
The interaction between a normally impinging shock wave and the boundary layer on a plate with slip is studied in the neighborhood
of the leading edge using various experimental methods, including special laser technology, to visualize the supersonic conical
gas flows. It is found that in the “non-free” interaction, when the leading edge impedes the propagation of the boundary layer
separation line upstream, the structure of the disturbed flow is largely identical to that in the developed “free” interaction,
but with higher parameter values and gradients in the leading part of the separation zone. The fundamental property of developed
separation flows, namely, coincidence of the values of the pressure “plateau” in the separation zone and the pressure behind
the oblique shock above the separation zone of the turbulent boundary layer, is conserved.
Moscow. e-mail: ostap@inmech.msu.su. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 3,
pp. 57–69, May–June, 2000.
The work was carried out with financial support from the Russian Foundation for Basic Research (project No. 97-01-00099). 相似文献
12.
The variational problem of optimizing the energy supplied to the discharge channel of a pulsed water jet in order to maximize
the mean jet outflow velocity is considered. The problem is solved in the gasdynamic formulation using the general method
of indefinite Lagrange multipliers. The optimality conditions are derived by considering the smeared flow. Both the direct
and conjugate problems are solved by the shock-capturing method. An example of the calculation is presented.
Donetsk. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 104–110, January–February,
1997.
This research was carried out under the program of the International Research Fund, grant No. U9600. 相似文献
13.
The results of an analytic and numerical investigation of the properties of the high-velocity “tails” of the distribution
function are given for the solution of the BGK model of the kinetic Boltzmann equation for plane Couette flow of a compressible
gas.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 4, pp. 183–190, July–August, 1998.
The work was carried out with financial support from the Russian Foundation for Basic Research (project No. 96-01-00573; grant
in support of leading science schools No. 96-15-9603). 相似文献
14.
A model of the heterogeneous catalysis of a dissociated carbon dioxide — nitrogen mixture on high-temperature heat-shield
coatings is developed; the model takes into account nonequilibrium adsorption-desorption reactions of nitrogen and oxygen
atoms and carbon dioxide molecules and their recombination in the Eley-Rideal reactions. On the basis of a comparison of the
calculated heat fluxes in dissociated carbon dioxide with those measured on the VGU-4 plasma generator of the Institute for
Problems in Mechanics of the RAS, the parameters of the catalysis model in question are chosen for three modern oxidant-resistant
coating materials. The performances of these coatings are compared for the conditions of Mars Miniprobe entry into the Martian
atmosphere. Their usability for the entry path considered is shown.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 106–116, January–February,
2000.
The study was carried out with the support of the Russian Foundation for Basic Research (project No. 99-01-00259) and the
“Integratisya“ Federal Program (project No. 2.1–414). 相似文献
15.
Data on the numerical solution of a system of kinetic Boltzmann equations for a homogeneous multicomponent mixture of reacting
gases with molecules of different “colors” that change in the reactions are given. The solution is obtained using a well-known
version of the direct statistical simulation (Monte-Carlo) method, namely, the majorant frequency method, under conditions
when the molecules belonging to the high-velocity “tails” of the corresponding distribution functions enter into the color
change reaction. The properties of the numerical solution are compared with solutions obtained within the framework of the
usual perturbation methods. It is shown that to obtain correct solutions over the range of threshold molecular velocities
it is necessary to modify substantially the procedure of the perturbation method, while the traditional approach can be used
only on the range of thermal particle velocities. Earlier, this was definitely established for distributions of the reacting
molecules over their internal degrees of freedom and for the distributions of reactant-molecules participating in a high-threshold
reaction.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 3, pp. 176–184, May–June, 2000.
The work was carried out with financial support from the Russian Foundation for Fundamental Research (project No. 96-01-00573)
and the Government Program for Leading Science Schools (grant No. 96-15-9603). 相似文献
16.
This paper provides an example of the application of Pressure Sensitive Paint (PSP) to complex internal suspersonic flows
and demonstrates the relationship between ejector wall pressure and aerodynamic performance. Details of such jet mixer-ejector
nozzles are relevant to jet noise reduction programs. Several ejector configurations with straight, convergent, and divergent
side walls were used in our experiments. The side-wall that was painted with PSP was also instrumented with an array of 156
pressure taps connected to Electronically Scanned Pressure (ESP) modules, enabling simultaneous measurement of “true” reference
pressures. The PSP results agreed very well with the “true” reference pressures and also provided a detailed map of the complicated
pressure patterns that could not be detected using the pressure taps. Finally, we also demonstrated the direct relationship
between ejector side-wall pressure distribution and ejector performance characteristics such as exit mean flow uniformity,
pumping, and thrust augmentation.
Received: 16 December 1997/Accepted: 21 August 1998 相似文献
17.
A series of curves bounding the region of existence of shock-free extremal exhaust nozzles is constructed for various values of the specific heat ratio. Outside this region the extremal nozzles contain focused suspended shocks.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 175–177, March–April, 1991. 相似文献
18.
The three-dimensional unsteady thermal convection developing in a cubic cavity on board the “Mir” station under the action
of the quasistatic component of the microacceleration caused by the earth’s gravity field strength gradient and the motion
of the station about the centre of mass is investigated numerically. The calculations are carried out for two real time intervals
of motion of the station about the centre of mass using actual values of the quasistatic component.
Moscow, Sankt-Peterburg. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 3, pp. 39–45,
May–June, 2000. 相似文献
19.
A. N. Andreyev 《Journal of Applied Mechanics and Technical Physics》1999,40(4):730-738
The stability of equilibrium of a layered composite circular conical truncated shell loaded with uniform external pressure
is investigated. A parametric analysis of the critical pressure intensities is carried out with allowance for the transverse
shear, the moment character of the subcritical state of equilibrium, and the subcritical strains.
Kemerovo State University, Kemerovo 650043. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 40, No. 4,
pp. 198–207, July–August, 1999. 相似文献
20.
The results of the numerical simulation of supersonic three-dimensional flow past sharp-nosed cones with circular and elliptic
cross-sections in the turbulent shock-layer flow regime are presented. The calculations are performed in the local conical
approximation using the system of Reynolds equations and the differential one-equation turbulence model. The numerical solutions
are obtained by means of an implicit constant-direction finite-difference scheme. The emphasis is placed on the investigation
of the transverse flow separation and the flow features associated with the turbulent flow regime.
St.Petersburg. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 99–105, January–February,
2000.
The study was carried out with the support of the Russian Foundation for Basic Research (project No. 99-01-00735). 相似文献