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This paper presents the results of liquid-fuel model combustor calculations based on different numerical approaches to the development of a verified simulation method of combustor operation. Both steady and transient studies were carried using various RANS turbulent models and the detached eddy simulation (DES) method. The results of these studies were compared with experimental data obtained by optical methods. The largest differences between experiment and calculations are observed for the near-axial flow field where recirculation backflow is formed. This vortex structure can be properly resolved in a DES simulation and in transient calculations based on the SAS SST model. The use of the above-mentioned approaches in combination with the flamelet combustion model provides maximum accuracy in predicting the parameters of reacting swirling flow, in particular the velocity and temperature distributions in the combustor.

This paper presents an experimental study of the lean and ultra-lean combustion of a multicomponent hydrogen-containing fuel in swirling flow under aerodynamic counterflow conditions. The subject of research was a counterflow burner module, which can be used to carry out the diffusion-kinetic combustion of a mixture of methane and a multicomponent hydrogen-containing gas in different concentration ratios. The experiments showed that the addition of the multicomponent fuel to methane extends the stable combustion range of lean mixtures and provides a reduction in the emission of polluting components in combustion products. These results can be used to increase the efficiency, safety, and service life of combustion chambers of gas turbine engines and power plants.

The results of particle image velocimetry near the perforated leading edge of the nozzle vane of gas turbine are presented. Visualization of the formation of cooling film on the surface of the blade with determination of its thickness is carried out. On the basis of the obtained results, the influence of the blown cooling air mass flow rate on the formation of the film is analyzed.

The results of numerical simulation of convective heat transfer under coaxial jet impinging on a surface are presented. The effect of jet's peripheral component swirling on the heat transfer enhancement by changing the number of tangential nozzles for creating jet is analyzed.

The paper considers issues related to droplet fragmentation in air flow. We present the results of calculating the equilibrium conditions for a rotating droplet. The shape of the droplet is assumed to be ellipsoidal, and the flow is potential. The droplet equilibrium is determined by the balance of pressure due to the surface tension force, the centrifugal force and the aerodynamic effect force of the flow. We obtained an analytic expression linking the equilibrium values of the Weber number, the ellipsoid aspect ratio and the dimensionless swirl parameter. The calculation results showed that droplet swirling has a significant effect on the equilibrium conditions in a narrow range of variation in the ellipsoid aspect ratio. We obtained critical values of the Weber number and the aspect ratios for which the equilibrium state of the droplet becomes unstable.

Numerical simulation of gas dynamics and combustion in coaxial swirled lifted propane-air jets under buoyancy conditions is performed. Dependences of dimensionless flame length L/d0, lift-off height h/d0 as well as flame front surface area Sfl and mass rate of burn-out U on orientation angle θ are obtained. The results of numerical simulation and experiment for different values of θ are compared. It is confirmed that in the angle range of 30° < θ < 60° flame has the smallest surface area that provides the highest value of the mass rate of burn-out. The numerical solution closest to an experiment data can be obtained by using an additional differential transport equation for the ignition time or setting a delay time in the range of 0.05..0.25 s.

Velocity fields measured in the vicinity of the perforated leading edge of a turbine nozzle vane using the particle image visualization technique are presented. Noncontact measurements were performed in a plane segment consisting of three nozzle vanes and having an optically transparent inlet section offering visual access to the region of the leading edge of the central vane for a high-speed camera and to the laser sheet. The experimental investigations were performed at a fixed incoming flow velocity of 33 m/s, and the relative air flowrate through the cooling holes varied from 1.6 to 6.4%. The cooling film flow near the leading edge was visualized for three models of vanes differing in the air supply method to the holes, hole diameter, and number. Supply of the coolant to the cooling holes from one cavity resulted in a high degree of nonuniformity in the distribution of the film over the leading edge, which was caused by a high blowing ratio for the jets injected through holes located closer to the suction side. The experimental results have revealed that separate supply of cooling air to the holes on the pressure side, leading edge, and suction size minimizes sensitivity of the formed film thickness to the relative flow rate of the coolant and provides a more uniform distribution of the coolant over the vane surface in a wide range of the blowing ratio for the jets that varies from 0.5 to 2.5. Visualization has demonstrated extensive unsteadiness of the film flow along the vane airfoil. In this case, the cooling jet fed through the central hole oscillates, thereby leading to periodic formation of a film on either the pressure side or the suction side.

Two different types of ejectors used for pumping gas, liquid and two-phase flows, as well as for evacuation of enclosed spaces have been analyzed. The results of CFD simulation of Dubinsky's Vortex ejector operation process are presented. The results of numerical simulation and experiment for different modes of ejector operation for passive flow and total back pressure are compared.

The main ways of cleaning the fuel injectors and the circuits of jet and vortex ejectors used for pumping gas, liquid and two-phase media, as well as for evacuation of enclosed spaces are analyzed. The possibility of organizing the process of pumping the liquid out of the fuel injection manifold secondary circuit using a vortex ejector is shown experimentally. The regimes of manifold evacuation at various inlet liquid pressure values are studied. The technology of carbon cleaning fuel injectors using a washing liquid at various working process parameters is tested.

Feasibility of using oxidant vortex reverse flow in designing jet burners for prospective combustion chambers fueled with synthesis gas. A complex of experimental studies of the reverse flow burner module fueled with methane with addition of synthesis gas is carried out; steady combustion concentration range is defined.