Solution to the problem of a swirling jet from an annular orifice

The problem of the propagation of a laminar immersed fan jet with swirling was considered in [1–3]. In [1], the jet source scheme was used to find a self-similar solution for a weakly swirling jet. An attempt to solve by an integral method the analogous problem for a jet emanating from a slit of finite size was made in [2]. In [3], the equations of motion for a jet with arbitrary swirling were reduced under a number of assumptions to the equations that describe the flow of a flat immersed jet. This paper gives the numerical solution to the problem of the propagation of a radial jet emanating with arbitrary swirling from a slit of finite size and an analytic solution for the main section of the jet.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 49–54, March–April, 1991.     

Mathematical simulation of unsteady flow past a wing with jets

The various approximate approaches to the investigation of the unsteady aerodynamic characteristics of an airfoil with jet flap [1–3] are applicable only for an airfoil, low jet intensity, and low oscillation frequencies. In the present paper, the method of discrete vortices [4] is generalized to the case of unsteady flow past a wing with jets and arbitrary shape in plan. The problem is solved in the linear formulation; the conditions used are standard: no flow through the wing and jet, finite velocities at the trailing edges where there is no jet, and also a dynamical condition on the jet. The wing and jet are assumed to be thin and the medium inviscid and incompressible.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 3, pp. 139–144, May–June, 1982.     

Development of a two-dimensional turbulent jet in an infinite space

The second and third terms in the asymptotic expansion of the stream function in the nonsimilar problem of the development of a two-dimensional turbulent jet in an unbounded space are found in final form. Results of experimental investigations of free turbulent jets are cited, and the effect of the initial velocity profile on the aerodynamic characteristics of the jet is considered. The problem of the development of a two-dimensional turbulent jet in an unbounded space has been considered in [1–3]. The existing solution is similar, and is valid only at a sufficiently large distance from the slit. Allowance for the finite dimensions of the slit leads to a nonsimilar problem. The papers [4–6] are devoted to the experimental investigation of the free two-dimensional turbulent jet.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 4, pp. 137–142, July–August, 1971.     

Plane underexpanded jet flowing out at an acute angle to a confined cross flow

The propagation of a sonic jet at an acute angle to a subsonic cross-flow induced by the jet itself is investigated experimentally. The dependence of the extent of the circulation zone and the rarefaction behind the jet on the degree of confinement of the cross-flow and the relative total pressure in the jet is found. The jet ejection properties is studied.Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 5, pp. 66–71, September–October, 1995.     

Effect of sound on a supersonic jet

It is known that under the influence of sound from an external source or the sound emitted by the supersonic jet itself at discrete frequencies in nonoptimal flow regimes the supersonic jet expands more rapidly and its range is reduced [1, 2], However, the mechanism of action of the sound on the supersonic jet has not been adequately investigated and, in particular, no one has determined the intensity of the external source capable of producing a marked change in the gas dynamic parameters of the jet, its characteristics or how the interaction process develops. These questions are examined below. By means of shadow photography with a pulsed light source it is shown that a significant change in the gas dynamic characteristics of the supersonic jet can be achieved by directing at its base along the normal to the jet boundary sound with an intensity corresponding to 0.1–0.2% of the total pressure in the jet. The appearance of large-scale disturbances on the irradiated side of jet and the directional emission of sound by the jet at the frequency of the external source are noted.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 6, pp. 170–174, November–December, 1989.The author is grateful to A. A. Kochetkov for assisting with the work.     

Investigation of the propagation of a two-dimensional wall jet over a step

The propagation of an underexpanded sonic jet over a flat end face has been experimentally investigated. As distinct from previous studies, the object of investigation is not a free jet, but a jet flowing from a nozzle along a horizontal surface. The total separation of the jet from the surface and its attachment to the end wall are related to the propagation characteristics of underexpanded wall jets. The effect of the total pressure in the jet and the height of the step on the separation of the jet and its attachment to the wall and, moreover, on the principal characteristics of the flow — the pressure in the base region, the extent of the circulation zone, the jet trajectory — is examined. The associated hysteresis effects are studied.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 4, pp. 61–66, July–August, 1991.     

Spread of jet from an annular slit around an air intake

The results of an experimental investigation of the flow created by a conical jet spreading from a narrow slit around the periphery of a suction intake are described. The reorganization of the jet flow associated with the resulting three-dimensional flow structure is investigated. A flow scheme is proposed.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 187–190, March–April, 1991.     

Effect of the wake on flow in an annular jet

The flow of an annular jet in a channel is studied. The effect of the Mach number of the wake on the structure of the jet is determined. It is shown that with a near-sonic velocity a reorganization occurs in the mode of flow from an open to a closed base region accompanied by a reduction in the level of pressure pulsations.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 6, pp. 74–79, November–December, 1974.     

Equations and forms of motion of a jet flowing onto a liquid

A nonlinear theory is constructed for a thin jet of nonviscous, incompressible, weightless fluid flowing from a nozzle onto the surface of an immobile heavy liquid. The theory is asymptotically (over jet thickness) more accurate than that presented in [1]. Forms of the flow are studied as functions of nozzle, jet, and heavy liquid parameters.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 6, pp. 20–28, November–December, 1976.     

Escape of a turbulent jet under the effect of acoustic perturbations

Results are presented of experimental investigations of the local effect of acoustic oscillations of different frequency and constant intensity on the root part of a nonisothermal axisymmetric subsonic turbulent jet escaping from a gas jet atomizer at a different velocity in the S = 0.053–3.84 range of Strouhaille numbers. Data have been obtained indicating the presence of unstable escape modes of a subsonic turbulent jet in an acoustic field; experimental dependences are presented of the relative aperture of the turbulent jet flowing in an acoustic field as a function of various parameters.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 1, pp. 58–62, January–February, 1972.The author is grateful to A. S. Ginevskii and B. S. Burikov for discussing the results of this paper, and also to A. S. Modnov and R. A. Arkhipova for assistance in conducting and processing the experiments.     

Flow of a jet from a slit-type source into a longitudinal carrying flow

It is shown that the problem of the mixing of a jet flowing out of an infinitely long slit-type source, with a homogeneous stream flowing parallel to the source of a jet, is analogous to the problem of the propagation of heat in a plane jet.Translated from Izvestiya Akademii Nauk SSSR. Mekhanika Zhidkosti i Gaza, No. 6, pp. 83–86, November–December, 1971.The author thanks Yu. Ya. Boldyrev for his aid in making the calculations in the present work.     

Some problems in the theory of plane jets of conducting fluid

Using the boundary-layer equations as a basis, the author considers the propagation of plane jets of conducting fluid in a transverse magnetic field (noninductive approximation).The propagation of plane jets of conducting fluid is considered in several studies [1–12]. In the first few studies jet flow in a nonuniform magnetic field is considered; here the field strength distribution along the jet axis was chosen in order to obtain self-similar solutions. The solution to such a problem given a constant conductivity of the medium is given in [1–3] for a free jet and in [4] for a semibounded jet; reference [5] contains a solution to the problem of a free jet allowing for the dependence of conductivity on temperature. References [6–8] attempt an exact solution to the problem of jet propagation in any magnetic field. An approximate solution to problems of this type can be obtained by using the integral method. References [9–10] contain the solution obtained by this method for a free jet propagating in a uniform magnetic field.The last study [10] also gives a comparison of the exact solution obtained in [3] with the solution obtained by the integral method using as an example the propagation of a jet in a nonuniform magnetic field. It is shown that for scale values of the jet velocity and thickness the integral method yields almost-exact values. In this study [10], the propagation of a free jet is considered allowing for conduction anisotropy. The solution to the problem of a free jet within the asymptotic boundary layer is obtained in [1] by applying the expansion method to the small magnetic-interaction parameter. With this method, the problem of a turbulent jet is considered in terms of the Prandtl scheme. The Boussinesq formula for the turbulent-viscosity coefficient is used in [12].This study considers the dynamic and thermal problems involved with a laminar free and semibounded jet within the asymptotic boundary layer, propagating in a magnetic field with any distribution. A system of ordinary differential equations and the integral condition are obtained from the initial partial differential equations. The solution of the derived equations is illustrated by the example of jet propagation in a uniform magnetic field. A similar solution is obtained for a turbulent free jet with the turbulent-exchange coefficient defined by the Prandtl scheme.     

Some problems of turbulent electrohydrodynamic jets

The problem of an axisymmetric turbulent electrohydrodynamic jet exhausting from a nozzle into an interelectrode gap is formulated. A numerical method of integrating the system of equations describing this flow is developed. This method is used to investigate three-dimensional effects in the jet (expansion of the jet, reverse flows). The influence on the jet characteristics (currents of the charge carried out of the nozzle, jet diameter, etc.) of the geometrical and electrical parameters and also of purely hydrodynamic factors (level of turbulence, relative velocity of parallel flow, etc.) is investigated.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 144–149, September–October, 1980.     

Determination of the base pressure during axisymmetric supersonic jet outflow into a channel

The outflow of an axisymmetric jet into a cylindrical channel of arbitrarily large cross-sectional area is considered. A method is proposed for analysis of the base pressure in the separation zone bounded by the inviscid jet boundary, the channel wall, and the step. New experimental results about the base pressure during jet outflow into a large-diameter channel are presented.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 6, pp. 125–129, November–December, 1973.     

Investigation of the flow structure in a plane turbulent jet

Results of an experimental investigation of a plane, submerged air jet are elucidated. The distribution of the mean velocity, the longitudinal and transverse velocity component pulsations, the tangential friction stress, and the correlation coefficient in jet cross sections are presented. The results of measurements are compared with the data of other authors.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 4, pp. 176–179, July–August, 1970.     

Laminarization of a submerged jet of electrically conducting fluid by means of a longitudinal magnetic field

A method of laminarizing electrically conducting jet flows by means of the combined use of a longitudinal magnetic field and inlet devices which form an initial velocity profile with smooth variation at the edge of the jet and a low perturbation level is proposed. An experimental investigation of delayed transition in a circular submerged jet, which demonstrates the high efficiency of the method, has been carried out.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 6, pp. 35–40, November–December, 1989.The authors are grateful to V. N. Kolomeits and V. P. Fomenko for helping to prepare and carry out the experiments.     

A turbulent jet with heavy components

The method of integral relationships is used to solve the problem of the initial and fundamental segments of a submerged turbulent jet containing heavy particles. The effect of the particles on turbulent structure of the jet is considered. Results for jet velocity on the axis and dynamic jet boundary agree with experiment.Translated from Izvestiya Akademii Nauk SSSR. Mekhanika Zhidkosti i Gaza, No. 6, pp. 41–49, November–December, 1972.     

Calculation of the trajectory of a plane free jet

A method is proposed for calculating the trajectory of a plane jet of an incompressible liquid, subjected to the action of two flows, directed at different angles to the original direction of the jet.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 3, pp. 178–182, May–June.     

Equations of viscous supersonic jets with a high degree of overexpansion

A complete system of equations determining a viscous laminar, strongly overexpanded jet is obtained; the system is formed by shortened Navier—Stokes equations, equations for the metric of a coordinate system related with the form of the jet, and equations of transition from curvilinear coordinates to Cartesian. The problem of calculating the jet is formulated as a Cauchy problem for this system. Two- and three-dimensional flows are examined. Possible swirling of the jet is taken into account.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 137–147, March–April, 1977.     

Influence of acoustic reflectors on the discrete component in the noise spectrum of a supersonic off-design jet

An experimental investigation of the discrete component in the noise spectrum of an axisymmetrie off-design jet emerging from a sonic or supersonic nozzle into a submerged space is conducted. The influence of the diameter of the reflector, placed at the nozzle edge, on the level, frequency, and phase diagram of the discrete component is examined. The discrete component in the jet noise spectrum has been studied in [1–7].Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 6, pp. 157–160, November–December, 1977.