On the transient regime in nonstationary supersonic flow past a body

The transient regime in gas flow past a stepwise accelerated body is analyzed by the method of singular perturbations at small Froude numbers. A marked effect of the initial conditions on the shock layer gas flow is demonstrated. The problem of flow past a wedge is solved in quadratures. St.Petersburg. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 111–121, January–February, 1997.     

The supersonic motion of a rigid body in an elastic medium with friction

The plane problem of supersonic steady motion of a body in an elastic medium is solved. Two possible cases of body motion are considered depending on its velocity. In the first case, the body moves at a velocity greater than the velocity of transverse waves but smaller than the velocity of longitudinal waves. In the second case, the body moves at a velocity greater than the velocity of longitudinal waves. An analytic solution of the problem under study is obtained and analyzed. It is shown that friction substantially influences the penetration process.     

Aerodynamics of axisymmetric bodies in supersonic flow with local blowing

Journal of Applied Mechanics and Technical Physics -     

Aerodynamics and static stability of star-shaped conical bodies in supersonic flow

The aerodynamics of conical bodies with a star-shaped cross section have been experimentally investigated over a broad range of variation of the parameters determining their geometry at a free-stream Mach number M=6. The position of the center of pressure of star-shaped bodies with an optimum trailing edge shape is investigated in relation to similarity parameters previously obtained theoretically. A correspondence is established between the derivatives of the normal force with respect to the angle of attack for pyramidal star-shaped bodies and bodies with the optimum trailing edge.Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No.6, pp. 142–150, November–December, 1992.     

A plane-parallel nonstationary motion of gas

A solution is found to the system of equations that describe plane-parallel nonstationary irrotational flows of an ideal gas under the condition that the velocity components of the gas depend on the polar angle and the time t.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Shidkosti i Gaza, No. 6, pp. 156–157, November–December, 1979.     

Experimental investigation of nonstationary flow in cavities in a supersonic flow

An experimental investigation was made into the flow and pressure pulsations in cylindrical cavities open toward a supersonic flow and set up at zero angle of attack (i.e., the cavity axis and the direction of the flow coincide).Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 180–183, September–October, 1979.     

Propagation of two-dimensional nonstationary vibrations in an electrically excited piezoceramic prismatic body

The paper outlines a numerical method to solve a plane problem for a piezoceramic prismatic body having rectangular cross-section and undergoing mechanically excited nonstationary vibrations. The features of the onset and propagation of vibrations are studied. The dynamic state of bodies with different widths is analyzed. The thickness and transverse displacements versus time are plotted Translated from Prikladnaya Mekhanika, Vol. 44, No. 11, pp. 71–78, November 2008.     

Arbitrary motion of an elongated body in an ideal fluid

A method is considered which permits the use of a computer to calculate the fluid velocity on the surface of a solid body moving in an ideal fluid and to calculate the added mass. The method of [1, 2], developed for bodies of revolution, in which the flow is simulated by a system of sources and sinks distributed continuously over the body surface, is extended to the case of an arbitrary body. In contrast with the analogous work of Hess and Smith [3], where the fluid velocities on the surface of an arbitrary body were determined for translational motions, in the present case the basic integral equation of the problem is solved by the method of successive approximations without preliminary approximation of the equation by a system of linear algebraic equations of high order, which leads to a shortening of the computations.The results of the calculations are compared with the known exact values of the velocities and the added mass for a triaxial ellipsoid, and also with the results of the experimental determination of the pressures on the surface of an elongated body.     

Unsteady viscous shock layer in the case of supersonic motion through an inhomogeneity

The model of a perfect gas is used in a numerical simulation of unsteady effects in a viscous shock layer near the stagnation streamline near the front part of a rotating blunt body in an inhomogeneous external flow with pressure difference P _t8, temperature difference T _t8, and vorticity difference . The evolution of nonlinear disturbances due to the passage of a heated region and a change of the injection regime is followed. A divergence finite-difference scheme of second order of approximation across the shock layer, realized by vector sweeps with allowance for the boundary conditions on the surface of the body and behind the separated bow shock wave, is used.Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 138–145, January–February, 1992.     

Immersion of a floating deformed body

A study is made of the plane-eddyless motion of an ideal incompressible liquid with the vertical uniformly accelerated immersion of a body, whose bottom is deformed in accordance with a given law. The method of solution of [1] is used. Dependences are given for calculating the pressures, the forces of the resistance to the immersion, and the forms of the free surface.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 136–137, September–October, 1974.     

Influence of blowing on the characteristics of the nonstationary boundary layer on an oscillating wedge in a supersonic stream

A study is made of the influence of blowing on the characteristics of a nonstationary boundary layer. For this, we solve the equations of the laminar boundary layer on an infinite wedge moving with supersonic velocity and executing small oscillations about the tip. It is shown that increased blowing improves the damping of the oscillations of the wedge.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 171–175, January–February, 1981.     

Experimental investigation of three-dimensional supersonic flow past an axisymmetric body with an annular cavity

The results of an experimental investigation of supersonic Mach 2.5 flow past an axisymmetric cylindrical model body with a rectangular annular cut-out on its lateral surface are presented. The evolution of the structure of the flow over the cavity with continuous variation in the angle of attack is studied on the basis of the data of flow visualization and balance measurements on the range of the relative cavity lengths L/h from 8 to 16. Hysteresis phenomena are revealed and analyzed.     

Effect of broken ice on the wave resistance of an amphibian air-cushion vehicle in nonstationary motion

The uniformly accelerated motion of an amphibian air-cushion vehicle on the surface of a basin covered by finely small ice floes is considered. Institute of Machine Science and Metallurgy, Far-Eastern Division, Russian Academy of Sciences, Komsomol'sk-on-Amur 681005. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 40, No. 6, pp. 48–53, November–December, 1999.     

Formation of separation zones in an asymmetric motion of a body in an elastic medium

We obtain an analytical solution of the problem on the motion of a body with wedge-shaped nose in an elastic medium for the case in which a medium separation zone may occur near the nose owing to asymmetry. The character of the dependence of the separation region length on the body velocity, the nose opening angle, the motion asymmetry degree, and the friction coefficient is found. It is shown that if the body moves at a velocity greater than the transverse wave velocity, then there is a limit velocity at which the separation region near the nose of the body disappears.