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On April 13, 2011 Chief researcher of Lavrentiev Institute of Hydrodynamics SB RAS, Doctor of Physics and Mathematics, Professor Vladimir B. Kurzin  was  80 years of age.

The paper considers the optical contact-free method of droplet diameter sizing in the flow cross-section utilizing light interference on a droplet. Distribution of light scattered by a particle was analyzed for different configurations of the measurement system using the Mie theory and approximation of geometrical optics. Basic measurement errors and dynamic range were determined. Possibility of measurements with camera mounting at the angle of 90º to the plane of a laser sheet is shown; this simplifies setup calibration and evens characteristics over the image field. The procedure of measurement system calibration and a set of algorithms for data processing are suggested. The suggested approaches were applied for measurement of characteristics of the gas-droplet jet.

A two-dimensional physical and mathematical model of the motion and heat and mass exchange of a steam and gas mixture with liquid droplets of variable mass in sprayer sprinkling chambers at high moisture contents is formulated by using the concepts of interpenetrating continua with different velocities and temperatures. An analysis of this model is carried out.

Propagation of acoustic waves in nanodisperse powders and powder flow under the influence of acoustic vibrations have been investigated in the horizontal tube with the use of visualization and hot-wire anemometer methods.

The technique of lifetime measurement for metastable liquid and continuous depressurization technique were applied for study of kinetics of spontaneous cavitation in superheated liquid argon under impact of weak ultrasonic fields. It was demonstrated that acoustic cavitation may occur through the mechanism of homogeneous generation of vapor phase or through swinging of vapor bubbles generated by high-energy particles and/or other kinds of initiative factors. The thresholds of acoustic cavitation are described by the theory of homogeneous nucleation.

Results of experimental investigation of the bubbly gas-liquid flow in a vertical annular channel are presented. The average and pulsation shear stresses and distributions of local void fraction were measured by the electrochemical method on both channel walls. It is shown that with a rise of gas flow rate ratio the value of wall shear stress increases significantly, and this effect becomes higher at a decrease in superficial liquid velocity. A presence of the gas phase effects significantly shear stress on the inner wall. Relative intensity of shear stress pulsations increases similarly on both channel walls.

Laboratory samples of small-sized energy converters based on thermo-electric method of heat conversion which source is diffusion microflame are presented in the work. Processes of combustion, energy conversion, and cooling in the proposed systems have been experimentally studied. Relatively high efficiency of the studied systems (energy-conversion 0.8 % at generated electric power of 130 mW) complying with the current world level for such devices is shown. The advantages of the proposed power generators are absence of forced-cooling system and catalysts, assemblage simplicity and usage of available materials and components. On the basis of investigation results, possible ways of further improvement of test samples have been determined with the view of energy conversion efficiency increase.

The effect of different scratch techniques, mainly abrasive papers and scalpel blades used to form the junctions of temperature sensors, on the thermal-product value of these sensors, was examined. A dynamic calibration procedure of scratched sensors in a shock tube facility which allows easy evaluation of their thermal-product value is outlined. The thermal product of a particular sensor was found to be dependent on the flow Mach number, junction scratch technique, junction location, and also on the enthalpy conditions. It was shown that using different scratch techniques normally results in different thermal-product values of sensors. The experimental procedure used in the present study has yielded practical data on characteristics of scratched temperature sensors; these data can be used in accurate measurement of transient heat transfer under hypersonic flow conditions.

We have experimentally proved the applicability of hot-wire anemometer method to measure fluctuations at low pressures and gas flow rates when medium is no longer considered as continuous. Use of individual calibration at working conditions serves to apply standard technique for determination of sensitivity coefficients of hot-wire probes. Additional investigations are necessary to take into account influence of Knudsen number and, possibly, other parameters in heat transfer law presented as criterial dependence of Nusselt number on Reynolds number. Hot-wire measurement of mean velocity distribution and their fluctuations in the flow-through path of electric-discharge CO₂ laser have been performed. The level of velocity fluctuations in the vicinity of anode is high that is caused by the zone of interacting flows from the ventilators rotating in opposite directions forming in the symmetry plane. Placing of the damping screen between the ventilator and air gap allows decreasing fluctuations intensity to the acceptable level. It has been ascertained that the vortex shedding with high intensity of fluctuations which influence is noticeable in significant part of air gap is formed in the wake behind the streamlined cathode. However, pulsation level in the proper gap does not exceed permissible values.

Different turbulence models were studied in application to calculation of swirling flows. The differential models of turbulent viscosity considering streamline curvature and the method of detached eddy simulation were used. Weakly and strongly swirling flows were considered at the example of concentrated vortex in a tube, swirling flow in a diffuser, and vortex breakdown through an abrupt expansion. The RANS models with correction to flow swirling represented well the experimental data for the weakly swirling flows. In case of strongly swirling flows, it was more correct to use the method of detached eddy simulation.