Speed of sound in two-phase vapor-liquid systems

The principal theorems of thermodynamics of irreversible processes are applied to the process of propagation of acoustic waves in a two-phase medium. Expressions are derived which determine the dependence of the sound speed in a vapor-liquid medium on the degree of dryness and the degree of nonequilibrium of different relaxation processes accompanying the propagation of acoustic waves. In the limiting case of equilibrium these expressions reduce to the well-known formulas obtained in equilibrium thermodynamics.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 5, pp. 78–85, September–October, 1970.     

Effect of capillary pressure on the approach to residual saturation

The approach to residual oil saturation during the immiscible displacement of oil as predicted by the multiphase Darcy equations is studied. It is well known that when the capillary pressure term is neglected, one arrives at the Buckley-Leverett formulation according to which the inlet face attains residual oil saturation instantaneously. This result may, however, be strongly influenced by the inclusion of the capillary pressure term. In this paper it is shown that when the relative permeability and capillary pressure functions have power law dependencies on the saturation deviation from residual oil condition, the long time solution exhibits a power law decay toward residual saturation. Moreover, the power law decay solution is found to be unique and independent of the initial condition. The relationship of this solution to the classical Buckley-Leverett result is shown. Finally, generalization to the time varying flow rate case is addressed. As a verification of the theoretical conjectures, the power law solution is compared with direct numerical simulation of the two phase flow equations.     

Measurements on the velocity of sound in oxygen gas under high pressure

Flow, Turbulence and Combustion - Using the acoustical interferometer for high pressures described in an earlier publication1) we measured the velocity of sound in oxygen gas between 1 and 70 atm...     

Dissipative effects of an isolated bubble in water on the sound wave

ＤＩＳＳＩＰＡＴＩＶＥＥＦＦＥＣＴＳＯＦＡＮＩＳＯＬＡＴＥＤＢＵＢＢＬＥＩＮＷＡＴＥＲＯＮＴＨＥＳＯＵＮＤＷＡＶＥＨｕｎａｇＪｉｎｇ－ｑｕａｎ（黄景泉）ＬｉＦｕ－ｘｉｎ（李福新）（ＮｏｒｔｈｗｅｓｔｅｒｎＰｏｌｙｔｅｃｈｎｉｃＵｎｉｖｅｒｓｉｔｙ,Ｘ...     

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.     

Role of saturation nonlinearity in the problem of forced synchronization

International Applied Mechanics -     

Effect of the wall on the ionic saturation current of a cylindrical probe

The hydrodynamic theory of electrostatic probes in a weakly ionized gas has been developed considerably (for example, [1–5]). However, the results obtained relate to cases of a single probe in the form of a plane, a sphere, or a cylinder. Only recently have investigations been made of such questions as the effect of the walls bounding a plasma on the characteristics of a probe, edge effects, etc. [6, 7], which is explained by the considerable difficulties in the solution of problems with sharply changing values along the boundaries, which includes also the problem of a probe in a dense plasma. In the present article it is shown that the investigation of three-dimensional and edge effects can be considerably simplified if we consider limiting conditions of the saturation currents. The article gives the results of a numerical solution of the problem of a cylinderical probe around a wall.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 182–185, September–October, 1976.     

无损伤肠道机器人运行速度的研究

提出了一种结构简单的微型肠道机器人的驱动机构,当它在人体大,小肠中运行时可减轻或消除肠道机器人在体内运行时给患者带来的不适与痛苦。同时分析计算了此种肠道机器人在体内的运行速度,形成的粘液膜厚度及其影响因素。计算结果表明,肠道机器人在大,小肠中运行时可以形足够厚的粘膜,从而将机器人与肠道壁隔开,实现无损伤运行;影响机器人在肠道中运行速度和形成的粘液膜厚度的主要参数有驱动机的螺纹参数,肠道粘液的粘度和     

Progration of sound in pulmonary parenchyma

Moscow. Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 3–15, September–October 1988.     

Velocity of sound in two-phase mixtures

Velocity of sound is computed for water, ammonia, Freon-12 and isobutane in two-phase mixtures in thermodynamic equilibrium. A computational method is developed which yields the sound velocity in terms of the thermodynamic coordinates of the substance (T, x) without the use of diagrams. Corresponding velocities of sound for the four substances considered exhibit a certain similarity which is examined statistically. The relationship between the sound velocity and the critical mass flux is also investigated.