I. K. Gimaltdinov

Specific features of the formation of gas hydrates during the injection of a cold gas into a porous medium saturated with a gas and water

A mathematical model of the process of the formation of gas hydrates in a porous medium during the injection of a cold gas is presented. The cases where hydrate formation is limited by the kinetics of the process and heat and mass transfer in a porous medium are considered. The influence of the initial parameters of the porous medium and the intensity of the gas injection on the dynamics of the processes of hydrate formation is studied. The critical conditions that separate the different modes of hydrate formation are found.

Numerical modeling of formation of a gas hydrate in a finite-length porous bed purged by a gas

The process of formation of a gas hydrate in a finite-length porous medium partially saturated with water, which is purged by a cold gas, is studied. The influence of the initial parameters of the porous medium and purging conditions on the evolution of hydrate saturation and temperature is examined.

Dynamics of detonation waves in an annular layer of a round pipe

The dynamics of axisymmetric detonation waves in a round pipe containing an annular near-wall bubble layer with a combustible gaseous mixture are studied. The situations in which within the annular layer there are a pure liquid or a bubbly mixture with an inert (unexplosive) gas are considered.

Two-Dimensional Pressure Waves in a Fluid with Bubbles

The specific features of wave evolution in a fluid with a finite bubble zone are studied. The two-dimensional effects are taken into account. The results for two-dimensional wave evolution in a uniform bubbly fluid are also presented.

Propagation of detonation waves along a tubular bubble cluster in liquid

The dynamics are studied of axisymmetric two-dimensional detonation waves in liquid with bubbles, where the bubbles are found in the form of a tubular cluster in the axial region of a pipe and where they are arranged in the form of a ring bubble layer. It is demonstrated that such clusters may serve as a waveguide for transmitting pulsed signals which are detonation solitons. It is found that, because of precompression of a bubble cluster by waves propagating in “pure” liquid, the velocity of detonation soliton may significantly increase compared to the case of one-dimensional bubble detonation.

Explosion of a bubble curtain with a combustible-gas mixture under the action of a pressure pulse

A bubble liquid with a combustible gas (e.g., water with either detonating-gas bubbles or a hydrocarbon– oxygen mixture) is an explosive. In this liquid, a detonation soliton with an amplitude of up to hundreds of atmospheres can arise under the action of a pressure pulse on the order of 10–20 atm [1]. The specific mass caloricity of such an explosive is lower by six or more orders of magnitude than for usual solid, liquid, and gaseous explosives. These low-caloric explosives are efficient means of amplifying and maintaining wave signals, as well as of temporarily elevating the pressure in local zones. In addition, in combustible liquids containing curtains with vapor–air bubbles, sharp shocks arising in the process of transportation can promote formation of detonation solitons leading to emergencies. In this paper, in the two-dimensional setting schematically presented in Fig. 1, we consider an explosion of a finite-size curtain in a liquid under the action of a pressure pulse. Results are also given related to the dynamics of formation and separation of one-dimensional detonation waves due to nonlinear phenomena arising in the process of pressure-wave propagation through the inhomogeneity boundary in a bubble system inhomogeneous with respect to its volume content. In order to describe the processes under discussion, we use the system of equations [2] written out in Lagrangian variables:

Nonlinear Oscillation of a Bubble Cluster in a Spherical Resonator

Induced nonlinear oscillation of a bubble cluster in a liquid-filled spherical resonator is studied. Two methods of affecting the resonator wall by pressure are treated. The first method involves an induced periodic variation of pressure on the resonator wall, and the second method involves the “basketball” mode of pumping energy into the bubble cluster. The cluster efficiency from the standpoint of attaining high temperatures is analyzed.

Recovery of Methane From Gas Hydrates in a Porous Medium by Injection of Carbon Dioxide

This paper presents a mathematical model for methane hydrate–carbon dioxide replacement by injection of carbon dioxide gas into a porous medium rich in methane and its gas hydrate. Numerical solutions describing the pressure and temperature variation in a reservoir of finite length are obtained. It is shown that the replacement process is accompanied by a decrease in pressure and an increase in temperature of the porous medium. It is established that during the time of complete replacement of methane from a reservoir decreases with increasing permeability of the porous medium and the pressure of the injected gas.

Evolution of linear waves in a liquid in the presence of a curtain of bubbles

We investigate certain features of the evolution of waves in an acoustically compressible liquid in passage through a curtain of bubbles between two parallel planes. We consider the problem of reflection from a plane solid wall separated from the liquid by a curtain of bubbles. Investigations showed that in relation to the duration of the pulse it is possible to select a curtain with corresponding parameters to moderate the effect of the wave on the wall.