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A system of multipoint diagnostics for pressure pulsations was used in experiments. The data is compared with the results of high-speed flow visualization for the case of a cloud cavitation flow past a smooth hydrofoil in a slit channel. It was shown that the shock mechanism is significant for development of the attached cavity. The main mechanism for detachment and shedding of a cavity is a re-entrant flow.

The spatial evolution of the flow structure formed by the movement of a submillimeter pulsed arc discharge in a magnetic field near a flat dielectric surface was studied in detail using optical methods (Schlieren method and PIV tomography). Due to good controllability of the dynamic and electrical characteristics of the discharge with high precision synchronization of the equipment, a high degree of detail of the flow pattern on small scales was achieved. The formation of a transversely located toroidal vortex propagating in the direction of the generated electromagnetic force is shown. The formation of a secondary flow in the tail of the jet was detected, which can be explained by the ejection of the surrounding gas into the region of reduced density.

The efficiency of a regenerative heat exchanger with an intermediate coolant and drop irrigation under winter operating conditions has been experimentally studied. It was found that the temperature efficiency of the heating and cooling columns increased with an increase in the packing irrigation density from 0.11 to 0.20 kg/(m²·s). The maximum temperature efficiency of 71 % for the heating column was obtained at an irrigation density of 0.21 kg/(m²·s). In the cooling column of the heat exchanger, the air flow from the room was cooled, and moisture was condensed there. In the heating column of the heat exchanger, the opposite process of intense evaporation of moisture and humidification of the air flow entering the room was observed. The maximum humidity efficiency of the heating column was about 80% at a packing irrigation density of 0.17- 0.25 kg/(m²·s).

A device that allows obtaining a highly rarefied flow of microdroplets for their subsequent use in various fields of technology or scientific research is considered. The created setup allows microdroplet obtaining in a periodic mode. The oscillation period is about 30 seconds. With the help of gas flow pulsations, relatively small drops are filtered, which gives a more uniform droplet size distribution.

A modeling study was performed for excitation of streamwise structures in a boundary layer with combustion. Modeling for undisturbed flow in a boundary layer is based on locally self-similar solutions for a boundary layer flow; these solutions account for streamwise pressure gradients and a heat source in the boundary layer with combustion that comply to simulated data. This undisturbed flow solution is a basis for solving a problem of interacting the external vorticity with a boundary layer (for the case of hydrogen-air combustion). We demonstrated that this type of interaction with the boundary layer generates intensive streamwise structure with velocity inhomogeneity in the lateral direction. These structures have the level of velocity higher than for the external vorticity velocity by factor of tens. Meanwhile, a maximum value of temperature inhomogeneity is much higher than for the velocity maldistribution.

Experiments were performed on formation of phase interface for a case of distilled water boiling on cylindrical surfaces with the diameter of 1 and 3 mm. During the experiment, a bubble boiling regime was ensured, these bubbles are detected with the high-speed PSV (Particle Shadow Velocimetry) technique with 8000 f.p.s. rate. Data processing provides for bubble size distribution and defines the mean separation diameter and the bubble growth rate as a function of heat flux. The effect of the boiling surface curvature on boiling characteristics was evaluated.

The experimental study was performed on the influence of surfactants on the bubble size distribution for a bubbly flow in an inclined tube. Measurements were performed for a round tube with the inner diameter of 32 mm at the gas flow rate 3.3, 5, and 8 ml/min and the tube inclination angles 30 - 60°. Diameters of gas bubbles and mean diameters were measured from the shadow images of bubbly flow. These parameters were recorded as a function of the tube inclination angle and the distance from gas injection site and the measuring zone. Adding of surfactants reduces the bubble detachment diameter and suppresses bubble coalescence.

The paper presents results of experiments on low-temperature entrained-flow gasification of raw biomass with a broad fractional composition in a pilot setup under atmospheric pressure with a diverging duct and upflow. Here the fuel source is a wet pine-tree sawdust with the mean size 0.25 - 0.50 mm and the maximum size of 5 - 6 mm. The gasifier parameters: air flow rate is 8-15 m³/h, solid fuel rate is in the range 7.3-19.5 kg/h. Тhe produced syngas has the heating value is the range 2.47-5.58 MJ/m³ and this fits the technical requirements for fuel gases used in internal combustion engines and in gas turbine plants.

A mathematic model developed for describing the methane pyrolisis processes in a low-size plasmatron setup. Calculations are compared with experimental results on pyrolisis products composition. The factors promoting the yield of useful products are estimated. If the exit reactor temperature is increased to 1500 -2000 K, this reduces the ethylene yield and increases the soot content with a minor increase in the hydrogen yield.

Method of differential scanning calorimetry was applied for measuring the specific isobaric heat capacity of yttria fully stabilized zirconia (15 wt. %), which is widely used in production of high-temperature structural cera-mics. New reliable experimental results were obtained on the specific heat capacity in the temperature range of 300 -1270 K of a solid state with the uncertainty of 2 - 4 %. A table of reference data for specific heat capacity of the ceramics is presented. The experimental data are compared with available reference data. The study found that for a wide range of temperature and Y₂O₃ concentration, the heat capacity of YSZ solid ceramics can be accurately evaluated using the Neumann-Kopp rule and also by the average atomic weight of the compound.