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On the basis of experimental data for a windwheel with large-aspect-ratio (up to 14) cylinders, a method making it possible to determine optimal parameters and main characteristics of a windwheel (power, high-speed) is proposed. Effects due to number of cylinders, their aspect ratio and speed of rotation, stream velocity, and generator load are analysed.

A model is proposed, which describes the work of the viscometer sensor of the physical pendulum type. The model enables the obtaining of data on fluid viscosity directly from the measurement of the settling frequency of sensor oscillations or the amplitude of these oscillations. To describe the sensor operation a numerical computational algorithm is developed. This method enables the solution of a wide class of three-dimensional laminar fluid flow problems involving moving solids of arbitrary geometry. The results of testing the proposed numerical technique are presented.

A new exact solution of a problem for motion equations of a solid and ambient viscous fluid is found.

This paper reviews the works of the 3rd International Workshop and Exhibition on Plasma Assisted Combustion, which dealt with the last achievements in the following scientific fields: fuel conversion and activation, plasma ignition of fuels and flame control, plasma generation and modelling, waste treatment and utilization, and promising industrial technologies.

The compressibility factor was calculated in a wide range of parameters including the critical region using the equations of state obtained previously for real gas and conditions and limitations formulated by the authors for the form (structure) of the equation of state. It was determined that maximal deviations of compressibility factor values calculated by these analytical equations from the experimental (tabulated) values occur mainly within the critical region. A corresponding correction was introduced into the initial equation, and the analytical equation accurately describing experimental data in a wide range of real gas state parameters, including the critical region, was derived. It was shown by the example of analysis of high-accuracy experimental data on thermal properties of helium in the critical region that data description by the proposed analytical equation is at least as good as that obtained by the equation of fluctuation theory (scaling). It is shown that the proposed equation meets the classical conditions at the critical point.

Speed of sound in the gaseous freon R-236ea with the purity of 99.68 mol. % has been measured by the method of ultrasonic interferometer in the range from 263 to 423 K and at pressures from 17 kPA to 4.2 MPa. Errors of temperature, pressure, and speed of sound measurement were estimated to be within +/- 20 mK, ± 1.5 kPa, and ±(0.1+0.2) % respectively. Temperature dependence of ideal-gas heat capacity of R-236ea has been calculated on the basis of the obtained data.

Experimental techniques for investigation of heat transfer in liquid mixtures of different types complimenting each other have been presented. The main attention is focused on the measurements under conditions of pulse heating. The paper opens the set of papers dealing with the elucidation of features characteristic of the heat transfer in pulse superheated mixtures, including metastable states with respect to the liquid-vapor and liquid-liquid equilibriums.

The gas motion through porous objects in the gravity force field with a non-uniform distribution of heat sources, which may arise as a result of natural or man-caused catastrophes (as the damaged power unit of the Chernobyl NPP), is investigated. The influence of different parameters of the heat-releasing zone on the process of cooling of such objects is analyzed with the aid of computational experiment. It is shown that the porous element heating is affected not only by the height of the heat-releasing zone and the heat-release intensity therein but also by the distance of the heat-releasing zone from the element inlet as well as by the width of the heat-releasing zone. The phenomenon of a reduction of the porous element heating with increasing distance of the heat-releasing zone from the porous element inlet is revealed. An ambiguous dependence of the porous object heating on the width of the heat-release zone is identified: at a growth of the heat-releasing zone width, the heating of the element may both increase and decrease depending on the distance of the heat-release zone from the element inlet.

Three-dimensional wave processes in vertically falling films of viscous liquid are considered. The 3D localized perturbations, which are studied insufficiently, are of a particular interest. The numerical method for watching evolution of initial perturbations was developed. The final stage of this evolution is formation of the 3D localized structures: solitons. The boundaries of 3D soliton stability were determined.

A Particle Image Velocimetry (PIV) system was used to perform an investigation into the effect of low concentration of dispersed phase on time-average and pulsating characteristics of the flow over the self-similar part of a two-phase jet emanating into ambient space filled with the same fluid. A phase discrimination procedure based on reflected intensity was introduced into routine practice. Distributions of mean and pulsating velocities in the carrier and dispersed phases of the gas-droplet jet were obtained. In spite of low concentration of the dispersed phase, large droplets present in the flow were found to reduce the intensity of velocity pulsations in the gas phase.