The complex technique using laser and video equipment in test conditions at the setups of the Laboratory of water turbines of the Leningrad Metal Plant has been developed to conduct laser ...measurements of velocity fields and video recording of cavitation phenomena based on the integration of the laser systems ("LAD - 0xx" and "Track-07 S"), created at the Kutateladze Institute of Thermophysics SB RAS (IT SB RAS) and JSC "IOIT." The Doppler anemometer allowed to achieve experimental distribution of the circumferential, axial, and radial velocity components at each point along the radius of the suction tube cone section of test experimental setup which has give information about vortex structure in suction turbine. The developed PTV method is described. The investigation of cavitation behind the turbine blade at test setup at velocities of 8-10 m/s is presented.
Two methods of synthesizing composite precursors for obtaining catalysts of the process of liquid-phase hydrogenation based on nickel and silica gel are considered. A comparative analysis is made of ...methods of synthesis as a function of methods of preparation is presented, and the influence of mechanoactivation on the textural properties of catalysts is also investigated. Bulk density, particle porosity, specific surface area, total pore volume, and the radial distribution of the pores were chosen as the main textural properties. X-ray phase analysis, scanning electron microscopy, and low-temperature adsorption of nitrogen were used for these purposes.
For the first time, silica gel-supported nickel hydrogenation catalyst has been synthesized via the mechanochemical method from oxides in a single stage. A set of data on the effect of the catalyst ...mechanochemical activation conditions on specific surface area, pore size distribution, crystallites size, and crystal lattice imperfection has been obtained. Activity of the obtained catalyst towards mild-conditions reduction of multiple carbon bonds in styrene, prop-2-en-1-ol, and diethyl maleate has been studied. Recommendations for establishing the optimal parameters for obtaining a nickel catalyst using mechanochemical synthesis have been elaborated.
The mechanochemical synthesis of the methanol synthesis catalyst was investigated. Comparative mechanoactivation of the individual components of the catalyst (copper oxide, zinc oxide, and aluminum ...oxide) as well as their mixtures was conducted under different conditions. The structural characteristics, obtained for the methanol synthesis catalyst by means of x-ray phase analysis, scanning microscopy, and low-temperature adsorption nitrogen, are discussed.
A new optoelectronic method of contactless measurement of the profile of the surface of large complexly shaped objects distinguished by a high degree of reliability and resistance to variations in ...the optical properties of the surface of objects over a broad range and to additive noise in the images is proposed. The method utilizes structurized illumination, phase triangulation, and identification of phase images with stepwise shift.
Results from an experimental assessment of the applicability of laser triangulators for measurements of the thickness of hot rolled product are presented. It is shown that phase inhomogeneities ...caused by strong temperature gradients introduce serious distortions into the optical signals of laser triangulators, which ultimately substantially increase the error.
A spectral method of detection of laser Doppler velocimeter signals in turbulent flows is proposed. The method is based on estimating the signal/noise ratio adapted to the width of the power spectral ...density of the signal and comparing its value with the recognition threshold. Numerical simulations show that the error of the signal/noise ratio estimates is 1% for different velocities of the turbulent flow. Physical experiments aimed at measuring turbulent aerodynamic processes show that the proposed method offers a possibility of eliminating the errors of calculating the mean value and the velocity deviation equal to 15 and 78% by means of eliminating the signals with low signal/noise ratios from the processing system. Application of the proposed method also ensures lower nonuniformity of the signal/noise ratio estimates than that ensured by the famous method developed by Tropea for a wide range of turbulent velocities.
The mechanochemical synthesis of the methanol synthesis catalyst was investigated. Comparative mechanoactivation of the individual components of the catalyst (copper oxide, zinc oxide, and aluminum ...oxide) as well as their mixtures was conducted under different conditions. The structural characteristics, obtained for the methanol synthesis catalyst by means of x-ray phase analysis, scanning microscopy, and low-temperature adsorption nitrogen, are discussed.
Laser technology for determining the geometry of the rotor of a hydroelectric generator under load, based on automated remote high-speed measurements through the ventilation channel of the stator ...using a semiconductor FMCW-lidar is described. The experimental model of the laser system was tested on an existing hydroelectric generator. Results of measurements of the geometry of a loaded rotor of acting hydroelectric generator No. 4 of the Sayano-Shushenskaya hydroelectric power station (type SVF/1285-42V4, 640 MW) have been obtained for the first time. The error of measurements made by this method based on laser technology in experimental form did not exceed 1%.
PDF
