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This paper presents the results of numerical simulation of magnetic field cumulation and the Joule heating of shaped-charge jets produced by explosive compression of a metal cone in which a magnetic field was preliminary generated. The problem is considered in an axisymmetric two-dimensional non-stationary formulation. The final electrical conductivity of the cone material is taken into account, and various methods of generating the initial magnetic field (using one or two solenoids) are considered. It is found that that during cone compression, the magnetic field induction can increase several hundred-fold. For a relatively low initial magnetic field induction on the cone axis (0.09-0.17 T), the temperature increase near the axis of the shaped-charge jet due to heating by eddy currents is 200-300 °C. This heating can be accompanied by thermal softening of the shaped-charge jet material and an increase in its ultimate elongation and hence penetration capability.

This paper presents preliminary results of refinement of the mathematical model of plasma transport in a helical open magnetic trap (HOMT). Plasma is contained in the device by transferring a magnetic field pulse with helical symmetry to the rotating plasma. The mathematical model is based on the stationary equation of plasma transport. The paper presents a method for taking into account the effect of the model coefficients using additional information. The calculated dependence of temperature on coordinates is obtained, which qualitatively agrees with the experimental data. Ordinary differential equations are obtained, which follow from the original model and can be used to refine the coefficients. The mathematical model is developed to predict the plasma confinement parameters in devices with a spiral magnetic field.

The crystallization of a gallium alloy in a rectangular flat cuvette located vertically under external electromagnetic influence has been studied experimentally. It has been shown that the speed of movement and shape of the crystallization front can be effectively controlled by changing the power parameters of the electromagnetic stirrer. A mode characterized by intense mixing flow and significant inhomogeneity of the crystallization front has been selected by varying the amplitude of electromagnetic forces. In this mode, changing the phase angles of the supply currents of the linear induction machine allows one to fundamentally change the topology of hydrodynamic melt flows at a constant power supply of the stirrer. This, in turn, leads to a change in heat and mass transfer characteristics and hence the conditions in the interfacial region, making it possible to indirectly control the homogeneity of the crystallization front and, to a lesser extent, the phase transition rate. The contribution of convection to flow formation and its influence on the crystallization process have been studied. In particular, it has been shown that thermal convection can lead to the formation of additional vortex structures near heat exchangers, which prevents metal crystallization.

Coupled aerodynamics and rigid body dynamics are used to develop a numerical method for the rigid motion of the object on the ground under shock waves based on the collision theory and dynamic mesh method. The effects of the mass and centroid height of the object on the rigid motion are analyzed. Furthermore, the effect of object motion on shock wave propagation is examined. The results suggest that the rigid motion behavior of the object remains similar under different positive pressure times; the motion laws of the object are similar under different masses, while a small mass can alter the rotational direction; increasing the centroid height can reverse the rotational direction, and diffraction may induce a further reversal when the centroid height increases to a certain value; the rigid motion reduces the pressure decay rate near the leeward side during shock wave propagation over the object.

The states of liquid albumin droplets sitting on a non-wetting horizontal elastic substrate which was first cyclically stretched and then relaxed have been studied experimentally. Multi-branch hysteresis of the states of the droplet gave been found. The number of hysteresis branches can be regulated by changing the law of motion of the substrate.

A setup for experimental studies of the structure, shape, and size of the gas-liquid interface under ultrasonic exposure and forced aeration has been developed. It has been found that ultrasonic exposure leads to a factor of about 1.5 increase in the interfacial area during aeration. The existence of an optimal intensity of ultrasonic exposure that provides maximum increase in interfacial area per unit supplied ultrasonic energy has been found.

The paper presents the results of the experimental study of the structure of a liquid microlayer at the base of vapor bubbles during water pool boiling using the method of light-emitting diode (LED) interferometry and a transparent design of the heating surface. Microlayer profiles were obtained at different time moments and the effect of heat flux density on its characteristics was analyzed. It is shown that the applied technique with a fairly simple optical scheme allows obtaining of up-to-date information on the structure and dynamics of the microlayer under bubbles during boiling.

The paper considers experimental data of superfluid helium dynamics in a U-shaped cylindrical channel filled with a backfill of metal balls. An experimental cell is presented, and the results of study are shown in the form of a time dependence for the position of vapor-liquid interface. The differences between the oscillations in a free channel and in confined conditions are discussed. For a channel with a finely dispersed porous structure, the oscillation amplitude significantly reduces and a stationary state of the interfacial surface is possible.

This paper presents the development of active control methods for vortex phenomena in hydro turbines. The flow pattern downstream of a simplified turbine runner was studied under conditions typical of a hydro turbine operating at partial load, which are prone to generating large-scale vortex structures and inducing powerful pressure pulsations. Active control was achieved through the injection of additional air jets into the center of the runner cone. The results of experiments covering velocity distributions, velocity pulsations, and pressure pulsations following the injection of jets are presented. Control jets, regardless of their orientation, successfully suppress pressure pulsations. However, jets oriented radially provide the most effective suppression of vortices and reduce the total flow swirl in the draft tube. The pattern of jet supply directly affects the formation of a recirculation zone downstream of the runner. Experimental data on optimal injection align with previous theoretical estimates based on flow linear stability analysis.

The results of an experimental study of the normal integral emissivity (NIE) of lithium, sodium, and potassium during melting and in the liquid state are presented. The research is realized by the radiation method. The experimental results are compared with the theoretical calculation of the NIE from the Foot approximation and analyzed. The behavior of the main thermophysical properties of metals in the melting point region is generalized for the position of alkali metals in the Periodic Table.