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Wind tunnel is constructed. It is characterized by a high degree of airflow laminarization. The main constructive element of this aerodynamic tube is the laminarization module. It allows the destruction of turbulent fluxes by providing a homogeneous laminar flow. In order to evaluate the performance of the developed aerodynamic tube, a series of experimental studies was conducted in the range of air velocity of 10-50 m∙s-1. To establish the laws of the distribution of flow parameters relative to the section the cross-sectional analysis method was used. It consists of forming a series of measuring planes that characterize the distribution of dynamic pressure and air flow velocity relative to the testing section. After that, the received experimental data are interpreted as three-dimensional graphic dependencies of the studied quantities. There is clearly observed a certain local area of stable values of dynamic pressure and flow velocity, after which they are sharply reduced in the direction of the walls of the section for testing. As a result of the analysis, a series of digital profiles of the distribution of dynamic pressure in the measuring planes of the testing section were obtained. Analysis of the obtained graphic dependencies allowed establishing of the uneven distribution of the dynamic pressure difference in the boundary layer zone along the inner perimeter of the test section is worth noting. Because of the side of the upper wall of the test section, the dynamic pressure difference is greater than the sidewall. This phenomenon is due to the difference in area of their blown air. Consequently, at a wall with a larger contact surface, a constant air stream experiences more loss of its kinetic energy than a wall with a smaller area. Especially this tendency is observed in the turbulent boundary layer. [ABSTRACT FROM AUTHOR]

The blown down wind tunnel tube has been developed. It provides a high degree of air flow laminarization. The uniqueness of this design is the presence of a system of air vortices destruction. This system contains a complex of metal grids, honeycomb straightener and contraction nozzle. The combination of these elements allows for low turbulence level and promote the air flow relative to its axis. The complex of measuring equipment for the establishment of operational characteristics in the test section has been performed. A four-channel probe has been developed to analyze the total pressure and air flow velocity in the measuring tunnel area. The design of this probe makes possible to analyze the boundary layers of air flow in a wind tunnel. The corrective algorithm of recombination for the obtained data and software for their analysis is developed. A prerequisite for developing an algorithm for the recombination of the obtained data and their subsequent visualization is the idea of sectoral analysis and averaging of the data of common areas of the measuring area. Besides the developed algorithm, the correction function for leveling the aerodynamic resistance of the design of the four-channel probe was included. Whereas it approaches the nozzle of static pressure, there is a distortion of the real data distribution on each of the probe tube. To confirm the adequacy of the developed algorithm and the correct functioning of the software developed on its basis, a series of experimental studies was conducted, which were based on the measurement of total pressure when placing objects that create aerodynamic resistance in the measuring section. A profile analysis of the data allowed to visualize correctly the distribution of total pressure around the investigated bodies, even in the place of its sharp difference. [ABSTRACT FROM AUTHOR]