The paper generalizes to the three-dimensional case the previously proposed two-dimensional mathematical model of the motion of a plasma formation in a constant transverse magnetic field. The complete system of single-fluid magnetogasdynamic approximation of the equations of the hydrodynamic method for plasma description under conditions of local thermodynamic equilibrium is simplified in the electromagnetic part. Instead of solving the complete system of Maxwell’s equations, Ohm’s integral law is applied to the conducting region with usage of empirical data. Earlier studies in a two-dimensional version of this model as applied to the problem of describing the motion of an arc showed its effectiveness and efficiency for the class of problems under consideration. The simulation results with proposed extended model are compared with previously obtained calculated and experimental data. Main integral and local features of flow structure are highlighted.

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The results of numerical study of flow structure and heat transfer in turbulent flow of air over a flat plate at q w = const with a rectangular rib with slit channel of different shapes: confusor, diffusor and const cross-section are presented. The slit channel is located between the plate and the lower wall of the rib. Numerical simulation is performed for an incompressible fluid in the framework of three-dimensional Reynolds-averaged Navier-Stokes (RANS) equations with a Kato-Launder k-ε turbulence model for turbulence closure. The parameter effects, including the slit channel sizes and shapes (confusor, diffusor and plane-parallel), on turbulent flow structure and normalized local heat transfer coefficients on the heat transfer surface are examined. It is established that the rib with a slit, especially with a confusor, substantially reduces the size of the recirculation region behind the rib due to the effect of the generated near-wall jet on main flow. In addition, in the presence of a slit between the wall and the rib, in transverse direction, a pair of symmetrical extended spots with high values of heat transfer coefficients relative to the middle of the plate is observed. Rib with a consfor slit having a longer confusor part (Case B2) provides the best overall heat transfer performance.

Results of direct numerical simulations of turbulent premixed combustion of methane-air mixture at model conditions in simple cubic computational domain at moderate Reynolds number Reλ∼50 and Karlovitz number Ka∼5 are presented. These conditions correspond to combustion regime with main oxidation reactions localized in thin area. Extended kinetic mechanism of methane oxidation is used for chemical reactions description. Laminar flame velocity values are obtained and compared with other results of 1D and 3D calculations. Thickness, form and local flame front structures are revealed based on computation results.