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Numerical simulation of metal surface alloying with impulse laser radiation has been performed. Impulse intensity influence on melt hydrodynamics and alloying substance distribution has been evaluated. For substance material, the authors used data on iron including dependence of surface tension on melt temperature and admixture concentration.

The mathematical model of radiation field in a semi-transparent medium formed under the action of incident collimated and diffusion radiation was developed and implemented numerically. To solve the problem, the approach on the basis of modified average flux method was developed. Method testing via comparison with results of other authors has proved its high reliability and accuracy. As an example, the effect of different factors on radiation field was analyzed: self-radiation of medium, scattering anisotropy, and bottom reflectance.

Unsteady flow and heat transfer of the heated cylinder with transverse and longitudinal oscillations in unbounded flow of viscous incompressible heat conducting fluid are considered. Influence of amplitude, frequency and direction of harmonic oscillations of the cylinder on the near-wake structure and heat transfer are investigated.

Experimental study was performed for operation of a centrifugal disk pump at atmospheric air pressure. The dimensionless parameters were developed for generalization of experimental data on flow rate and head of the pump. The method for calculation of a pumping curve and throttling characteristic was offered through use of semiemperical generalization formulas. The method ensures a good accuracy in calculations, which is proved by comparison of calculation and experimental data for the pump tested.

The modification of absorption optic method for diagnostics of the wave liquid film on the surface of a rotating disk was proposed. Inaccuracy of the method was estimated analytically and experimentally. The field measurements of liquid film thickness on a rotating disk were carried out.

Evolution of disturbances on the surface of liquid film falling free over a vertical plane is considered. In the case of low Reynolds numbers, the problem is reduced to investigation of a single equation describing evolution of film thickness disturbances. With the use of information about the structure of the family of steady-state traveling solutions to this equation, the typical scenarios of evolution for periodic disturbances were identified.

The process of development of the third heat transfer crisis for vertical orientation of the heating surface was studied experimentally. Experiments were carried out with acetone under the conditions of saturation for the pressures in the working volume from 20 to 28 kPa. In all experiments, the third heat transfer crisis was preceded by propagation of evaporation front along the heating surface. The threshold values of heat flux densities, above which a stable vapor film is formed on the whole heating surface, are lower for vertical orientation of this heating surface than for the horizontal one. Data on the threshold heat flux densities and overheating before boiling-up were obtained. Above these values, formation of evaporation fronts was observed. The range of operation parameters corresponding to formation of the sites of unstable film boiling on the heating surface after boiling-up was determined.

Investigation results on hydrodynamics, heat transfer, and crisis phenomena in laminar-wave liquid films falling down the surfaces of different geometry are presented in this study. Freon mixture R21/R114 with initial concentration of low-boiling component of 4−16.6 % was used as the working liquid. The film Reynolds number at the inlet to the experimental section varied from 60 to 700. The heat flux density was changed within 0−5 W/cm². The images of wave surface of the falling liquid film and formation of dry spots were visualized and recorded by the high-speed video camera. Results of investigation of the wave structure of the film surface, measurements of heat transfer coefficients under the conditions of boiling, and critical heat fluxes in the film flow over the smooth and structured surfaces are presented.

The work is devoted to investigation of thermophysical processes occurring at granulation of lead-containing aluminum alloys. The researchers proposed the mathematical model of heat transfer that served a basis for calculation of cooling of the alloy drops with different dimensions. With the use of laboratory experiment, the boundary conditions of simulation have been specified, and the quality of the obtained granules evaluated.

The article presents results of the research of particulate matter and droplets removal on inclined tubes of the flue gas cleaning condenser in the process of vapor condensation of vapor-and-gas emissions from kraft pulp production.