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Results of route censuses of birds from December 1983 to late January 1988 carried out in southern taiga forests of the Middle Ural mountainous province (Sverdlovsk Region) in four key sites two of which are situated on the western slope and two are on the eastern one have been analyzed. Totally, 4 classification schemes have been drawn up: two on 31 habitats available in the sample, on the average for the first (May 16

Results of long-term studies of ornithofauna of Miassa City (Chelyabinsk Region, the South Ural) have been summarized. The species composition, abundance and ecological structure of the bird population in various districts of the city have been analyzed. It is demonstrated that during the last decades an enrichment of the city ornithofauna by

Changes of bird population density in the process of desertification of tugais caused by disturbances of the water regime of the river Vakhsh have been analyzed.

Long-term censuses of common crane in the West Siberian plain make it possible to assert that their average numbers exceed considerably the earlier found values. The majority of common cranes are in the steppe zone (45 % of the total numbers), less in taiga subzones (3 to 9 %). In the forest-tundra and tundra zones, no common cranes have been found.

In the basin of the middle and lowe reaches of the Abakan river, the faunistic composition has been studied, the altitudinal distribution and spatial-typological structure of buffalo gnat communities has been elucidated in an ecological water body series. The main changes in the buffalo gnat population iare associated with absolute altitude of the locvality, water temperature, fater flow width and velocity, and with granulometric composition of the ground.

Investigation results on unsteady vortex breakdown obtained simultaneously using two diagnostics methods: a) determination of a velocity field by particle tracks (particle image velocimetry – PIV), b) determination of velocity field by Laser Doppler Anemometry (LDA), are presented. The experiments data are in some regimes supplemented by the 3D computations of the incompressible Navier – Stokes equations in cylindrical coordinates. Perfect agreements between calculation and experiment reveal efficiency of both suggested diagnostics method for pulsating vortex breakdown and numerical method for solution to 3D un-steady Navier – Stokes equations.

The equation of convective diffusion of particles is considered, and the problem is formulated on the separation of dust particles from a turbulent gas flow in a parallel flow cyclone. The equations of pulsation motion of particles in the field of the action of the centrifugal and Coriolis forces are analyzed, and an analytic dependence is obtained for their diffusion coefficient.

The structure of nonstationary vortical wakes of the rotor was studied experimentally in the system of rows stator – rotor – stator of the axial compressor. It was established that besides deceleration of relative flow velocity in the zone of turbulent vortical wake of the blades, a layer of free vortices develops at the wake axis. The free vortices pulsate with the frequency of passing of blades between neighbor rows, causing pulsation in velocity, pressure; and due to mixing process the total pressure loss becomes higher.

The transonic regime of the flow around the airfoil is modelled in conditions of an pulse periodic energy. The objective of the present work is to study the effect of energy release on flow structure: decay and generation of shock waves, change of their position and strength as well as other effects caused by the flow reconstruction. The computed results are presented for the ideal gas flow around the airfoil NACA 0012 with the freestream Mach number of 0.8 for different locations of energy zones and values of the energy released. The flow was modelled on the basis of two-dimensional nonstationary gas dynamics equations. The stationary flow around the airfoil without the energy release was used as the initial condition. The explicit finite volume method diminishing the total variation (the TVD reconstruction) was used to find the numerical solution. The nonstationary problem was solved from the moment of time when the energy release is started up to obtaining a periodic regime. The possibilities are shown to control both the local and integral characteristics of airfoils at transonic flow regimes. A periodic character of the forming flow is established, which may be implemented at cruise flight speeds. The examples of both global and local flow reconstruction are presented.

Results of experimental investigations of a flow around airfoils in the subsonic wind tunnels are presented. The investigation objective is to compare flows above the upper surfaces of a smooth unswept wing and a waved one imitating a wing of a paraplan. Three-dimensionality of the flow structure in the zone of laminar separation bubbles is revealed, and their formation peculiarities on the smooth and waved wings are shown. Normal and tangential components of an aerodynamic force affecting the wing are measured, and the advantages of the paraplan over the planar wing are shown.