Dispersion of a plasma cloud in a uniform magnetic field

The numerical solution of the two-dimensional gasdynamical problem of the dispersion of a plasma cloud in a magnetic field which is uniform to infinity is described. The disturbance of the field and the deformation of the cloud are taken into account self-consistently.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 4, pp. 146–148, July–August, 1974.In conclusion the authors thank A. I. Barchenkov, G. V0 2harova, S. A. Kuchai, V. G. Rogachev, and V. P. Statsenko for valuable advice and assistance in the work.     

Experimental investigation of the flow of a vibrationally nonequilibrium gas in a profiled nozzle

The results are given of measurements of the gain in a planar profiled nozzle for a mixture containing carbon dioxide gas and nitrogen with admixtures of oxygen and water vapor.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 203–206, January–February, 1980.We thank V. A. Poltoratskii for assistance in the experiments and G. D. Smekhov and S. A. Losev for helpful discussions.     

Blowing into a supersonic stream through a permeable surface

Distributed blowing of gas into a supersonic stream from flat surfaces using an inviscid flow model was studied in [1–9]. A characteristic feature of flows of this type is the influence of the conditions specified on the trailing edge of the body on the complete upstream flow field [3–5]. This occurs because the pressure gradient that arises on the flat surface is induced by a blowing layer whose thickness in turn depends on the pressure distribution on the surface. The assumption of a thin blowing layer makes it possible to ignore the transverse pressure gradient in the layer and describe the flow of the blown gas by the approximate thin-layer equations [1–5]. In addition, at moderate Mach numbers of the exterior stream the flow in the blowing layer can be assumed to be incompressible [3]. In [7, 8] a solution was found to the problem of strong blowing of gas into a supersonic stream from the surface of a flat plate when the blowing velocity is constant along the length of the plate. In the present paper, a different blowing law is considered, in accordance with which the flow rate of the blown gas depends on the difference between the pressures on the surface over which the flow occurs and in the reservoir from which the gas is supplied. As in [8, 9], the solution is obtained analytically in the form of universal formulas applicable for any pressure specified on the trailing edge of the plate.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 108–114, September–October, 1980.I thank V. A. Levin for suggesting the problem and assistance in the work.     

Experimental investigation of the starting of a wedge-shaped nozzle of a large-diameter shock tube

The results are given of an investigation into the starting of a wedge-shaped nozzle of a shock tube. It is shown that in the regime of starting with overexpansion the main losses of the working time are associated with the secondary shock wave and in the considered sections of the nozzle occupy about half the complete duration of the starting. The application of the results to the investigation of the starting of wedge-shaped nozzles of various geometries is discussed.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 6, pp. 152–156, November–December, 1979.We thank O. P. Shatalov and L. G. Gvozdev for helpful advice and discussions, and also Yu. V. Akimov for assistance in the experiments.     

The spectrum of small perturbations in plane couette-poiseuille flow

The spectrum of small perturbations of plane Couette-Poiseuille flow is studied. The perturbations are classified according to their behavior at large wave numbers. The changes in the spectrum are traced as the transition is made from Poiseuille to Couette flow at fixed Reynolds number. The behavior of the perturbations is considered as a function of the Reynolds number.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 2, pp. 63–67, March–April, 1971.The author wishes to thank M. A. Gol'dshtik for his attention to the paper, V. A. Sapozhnikov for useful discussions, and V. N. Shtern for his great assistance and help with the paper and for useful discussions.     

Piston problem with allowance for finite rate of exothermic reactions and nonlinear heat conduction

One-dimensional nonstationary flows of a combustible mixture of gases are considered with allowance for nonlinear heat conduction. The possible existence of similarity solutions is studied, and conditions are found under which such solutions do exist. The results are given of a numerical calculation of the similarity problems of a piston and self-sustaining thermal wave.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1. pp. 146–151, January–February, 1979.I thank V. A. Levin for continuous assistance in the work.     

Numerical solution of the two-dimensional nonstationary problem of the motion of a shell under the action of detonation products

The problem of the motion of an incompressible cylindrical shell with an explosive charge is solved numerically for the propagation of a plane detonation wave from the end of the charge. The strength of the shell is not taken into account. A three-term equation of state [1] is assumed for the detonation products. A comparison is made with the one-dimensional case.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 4, pp. 76–79, July–August, 1972.The authors thank G. S. Roslyakov and V. M. Paskonov for assistance in the work and for helpful advice.     

Experimental investigation of the effect of longitudinal riblets on the friction drag of a flat plate

The results of a gravimetric investigation of the effect of longitudinal riblets on the friction drag of a flat plate are presented. The experiments were carried out with both natural and artificially thickened developed turbulent boundary layers in a zero-gradient flow.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 140–145, March–April, 1987.The authors wish to thank V. V. Mikhailov for his valuable assistance.     

Allowance for nonuniformity of the flow at the minimal section in optimal profiling of the expanding part of a nozzle

A study is made of the problem of allowing for the real nonuniform distributions of the flow parameters at the minimal section of a Laval nozzle in the problem of constructing its supersonic part in such a way as to maximize the thrust for fixed counterpressure and fixed maximally allowed dimensions.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 184–186, January–February, 1981.We thank L. E. Sternin, who initiated the present investigation, and also V. A. Bugrov and N. N. Slavyanov for assistance in calculating the subsonic and transonic flows.     

Forms of annular streams of trickling liquid

An investigation is made of the development of axisymmetric thin annular streams of trickling liquid flowing from an annular aperture at an arbitrary angle to the symmetry axis in an unperturbed ideal medium. A classification of possible forms of the stream is given, taking into account the action of surface-tension forces and the pressure differences at the external and internal surfaces, but neglecting gravitational forces. A qualitative analysis of the differential equation for the form of the stream is given, together with some results of its direct numerical integration, taking into account gravitational forces.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 9–14, January–February, 1977.In conclusion, thanks are due to V. Ya. Shkadov for his interest in the work and critical comments.     

Asymptotic theory of short separation regions on the leading edge of a slender airfoil

The two-dimensional flow of a viscous incompressible fluid near the leading edge of a slender airfoil is considered. An asymptotic theory of this flow is constructed on the basis of an analysis of the Navier—Stokes equations at large Reynolds numbers by means of matched asymptotic expansions. A central feature of the theory is the region of interaction of the boundary layer and the exterior inviscid flow; such a region appears on the surface of the airfoil in a definite range of angles of attack. The boundary-value problem for this region is reduced to an integrodifferential equation for the distribution of the friction. This equation has been solved numerically. As a result, closed separation regions are constructed, and the angle of attack at which separation occurs is found.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 42–51, January–February, 1981.I thank V. V. Sychev and Vik. V, Sychev for assistance.     

Heat transfer at the nose of a blunt body in a rarefied supersonic flow of a nitrogen-hydrogen mixture

The temperature-recovery factor and specific heat flux have been measured at the nose of a spherically blunted body in a low-density supersonic stream of a nitrogen-hydrogen mixture. The experiments were carried out in the transition flow regime from continuous to free-molecular flow. The measurements show that the values of the recovery factor and heat flux in the mixture are larger than in the pure gases.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 6, pp. 88–91, November–December, 1973.The authors are grateful to I. F. Zavarzina and P. G. Itin for assistance.     

Internal waves generated in an exponentially stratified fluid by an arbitrarily moving source

A theoretical investigation is made into the development of linear internal waves in an exponentially stratified flow of an ideal incompressible fluid in the Boussinesq approximation. The waves are generated by an arbitrarily moving point mass source. The obtained solution is used to investigate three special cases of motion: uniform motion at an angle to the horizontal, nonstationary motion during a finite interval of time, and uniform motion in a circular path. The method of solution of this problem is similar to that used by Wolfe and Lewis [1], who studied the generation of acoustic waves.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 3, pp. 67–74, May–June, 1980.I thank V. V. Sazonov for assistance in the calculations.     

Dynamics of a diverging liquid meniscus in a capillary,taking into account the specific properties of thin films

The theory of the diverging meniscus of a Newtonian liquid for capillary flow conditions at low meniscus velocities, in which the thermodynamic and Theological features of thin wetting films appear, is set forth. Two cases are considered: thermodynamically stable wetting film with high viscosity in the boundary layer on a completely wetted solid surface and a thermodynamically unstable film on a conditionally wetted solid surface exhibiting a liquid slip effect.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 3, pp. 72–82, May–June, 1976.The author wishes to express his appreciation to A. G. Grivtsov and V. S. Yushchenko for valuable assistance in the computer calculations.     

Two-dimensional spreading of a cloud of conducting gas in a magnetic field self-similar solution

A self-similar solution of the problem on the spreading in a magnetic field of a cloud of conducting gas, having the shape of a cylinder of noncircular cross section, is constructed. The cylindrical surface of the gas is restrained by a nonconducting sheath that spreads according to a prescribed law. The shape of the transverse cross section of the cylindrical cloud is determined from the solution. Cross sections obtained for a concrete case are represented in graphic form.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 2, pp. 29–36, March–April, 1973.In conclusion the author thanks V. I. Khonichev for assistance with the numerical calculations.     

Experimental investigation of the heat exchange in separation zones of a turbulent boundary layer ahead of a step

Results of an experimental investigation of the heat exchange in separation zones of a two-dimensional turbulent boundary layer ahead of a rectangular step are elucidated for a subsonic air stream velocity.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 1, pp. 126–131, January–February, 1971.The authors are grateful to V. S. Avduevskii for discussing the results of the research.     

On profiling planar and axisymmetric nozzles and channels to achieve a given supersonic stream at the exit section

Under the assumption of an ideal gas, methods are described for profiling the supersonic parts of planar and axisymmetric nozzles and channels in order to achieve given, in the general case, nonuniform fields of the parameters at the exit section. Besides shockless arrangements, configurations are considered in which the required distributions of the entropy are produced by a shock formed by the flow past a specially profiled wall.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 4, pp. 94–102, July–August, 1981.We are grateful to V. A. Vostretsova for assistance in the work.     

Compression curve of a fibrous composite

Results are presented of an experimental investigation of a single-directional fibrous composite under compression in the bonding direction. The buckling modesare detected: the customary bending and a shear mode which holds for comparatively low sample flexibilities.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 4, pp. 155–160, July–August, 1971.The authors are grateful to V. P. Gryaznov for assistance in preparing the samples.     

Self-oscillational motion of a cylinder towed in weak aqueous polymer solution

A study is made of the effect of polymer additions on the nonstationary vibrational motion of a cylinder towed in a weak aqueous solution of the polymer and capable of making transverse displacements under the action of the force arising from asymmetry of the periodic detachment of the boundary layer. The Reynolds number was 3·10³–10⁴.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 162–164, 1973.The authors wish to thank V. P. Borovikov for his assistance in organizing the experiments.     

Numerical investigation of two-phase flow with coagulation and fragmentation of particles in axisymmetric laval nozzles

The method and results of a calculation of the parameters of a polydis-perse two-phase flow with coagulation and fragmentation of particles in collisions are described. The problem is considered in a two-dimensional formulation. The secondary particles (fragments) formed by fragmentation are assumed to have arbitrary mass and velocity distributions.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 3, pp. 145–153, May–June, 1982.We thank F. G. Gaponich for assistance in the computer calculations.