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Results of a numerical study of the thermal effectiveness of a gas wall screen implemented via gas blowing through cylindrical inclined holes embedded in a transverse trench are reported. The calculations were performed using 3D Reynolds-averaged Navier–Stokes equations, with the flow turbulence being modeled by means of the Reynolds-stress model. Blowing into the trench was compared to the conventional cooling technique using gas blowing without a trench. The film cooling effectiveness with gas injection through circular holes embedded in trench exceeds significantly the effectiveness of blowing without a trench. Such a method of coolant supply into the flow proved to be especially advantageous at high blowing ratios. Due to the formation of vortical structures inside the trench, a more uniform cooling flow in the spanwise direction can be achieved. A comparative analysis is indicative of acceptable qualitative agreement of the experimental and predicted data.

The plane oscillations of the elliptic cavity filled with a viscous incompressible liquid have been investigated numerically. Characteristic decay time depending on the values of system parameters has been determined, the values of parameters at which this time is minimum have been found. Flow patterns of liquid in the cavity are presented.

The density and thermal expansion coefficients of liquid potassium–lead alloys (30.01, 39.99, 50.00, 66.66, 84.40, and 90.70 at. % Pb) have been determined using gamma-ray attenuation technique over the temperature range from liquidus line to 975 K. The experimental uncertainty of the density measurement is estimated to be within ±0.2–0.4 %. A comparison of the obtained results with literature data has been made. Temperature and concentration dependences of the volumetric properties of liquid K–Pb system have been built and analyzed.

The flow around a model in the closed test section of a low-speed wind tunnel has been analyzed in 2D approximation. As the contour of the nozzle, test section, and diffuser, the contour of the T-324 wind tunnel, of the Khristianovich Institute of Theoretical and Applied Mechanics (ITAM SB RAS, Novosibirsk), in its symmetry plane was adopted. A comparison of experimental with calculated data on the distribution of velocities and dynamic pressures in the test section is given. The effect due to the sizes of a model installed in the test section on the values of the aerodynamic coefficients of the model is analyzed. As the aerodynamic model, the NASA0012 airfoil and the circular cylinder were considered. For the airfoil chord length b = 20 % of nozzle height, the values of the aerodynamic coefficients of the airfoil in the free stream and in the test section proved to be close to each other up to the angle of attack α = 7°, which configuration corresponds to blockage-factor value ξ ≈ 7 %. The obtained data are indicative of the expedience of taking into account, in choosing the model scale, not only the degree of flow passage area blockage by the model but, also, the length of the well-streamlined model. In the case of a strongly blunted body with a high drag-coefficient value, the admissible blockage factor ξ may reach a value of 10 %.

The paper formulates the issue of development of experimental base with noninvasive optical-electronic tools for control of combustion in a combustion chamber of gas turbine engine. The design and specifications of a pilot sample of optronic system are explained; this noninvasive system was created in the framework of project of development of main critical technologies for designing of aviation gas turbine engine PD-14. The testbench run data are presented.

The work presents a method of complex investigation of thermal radiation emitted by heterogeneous combustion products in the model rocket engine plume. Realization of the method has allowed us to obtain full information on the results in all stages of calculations. Dependence of the optical properties (complex refractive index), the radiation characteristics (coefficients and cross sections) and emission characteristics (flux densities, emissivity factors) of the main determining factors and parameters was analyzed. It was found by the method of computational experiment that the presence of the gaseous phase in the combustion products causes a strongly marked selectivity of emission, due to which the use of gray approximation in the calculation of thermal radiation is unnecessary. The influence of the optical properties, mass fraction, the function of particle size distribution, and the temperature of combustion products on thermal radiation in the model rocket engine plume was investigated. The role of "spotlight" effect – increa-sing the amount of energy of emission exhaust combustion products due to scattering by condensate particles radiation from the combustion chamber – was established quantitatively.

A mathematical model was developed for accumulation of oil in a cylindrical tank (the dome-separator) designed for capturing of oil from oil leakage at the sea bottom. Two key stages were described, and time dependencies for interface evolution and alcohol layer temperature were calculated.

On June 17, 2015 Robert I. Nigmatulin, the prominent scientist specialized in mechanics and mathematics, academician of the Russian Academy of Science became 75 years of age.

On June 26, 2015 Professor Anatoliy P. Burdukov, Doctor of Technical Sciences, the Laureate of the State Prize in Science and Engineering, the Honored Worker of Russian Science, became 80 years of age.

Data on the concentrations of heavy metals and lithium in the bottom sediments of Lakes Ladozhskoye (northern region) and Chetyrekhverstnoye (Petrozavodsk) are reported. The dependence of the concentrations of studied microelements on sampling depth and a correlation between lithium and heavy metals in the studied samepls of lake sediments were demonstrated. It was proved that lithium nay be used for granulometric normalization of the concentrations of heavy metals in the studied water objects and thus it may be used to evaluate the level of techynogenic pollution of lakes in Karelia. Higher level of the pollution of bottom sediments in the city Lake Chetyrekhverstnoye by lead, copper and nickel in comparison with the sediments of Lake Ladozhskoye was detected, while the sediments in Lake Ladozhskoe were found to be polluted with zinc to a higher extent.