46 research outputs found
Development of engineering method for calculation of ejected and recirculated air flow rates during reload of bulk materials
Reload of bulk materials in various industries and agriculture are accompanied by significant dust emissions. The flow of bulk materials in its fall carries air (air ejection). The study of the flow of ejected air is a complex multidisciplinary task. The maintenance costs of local exhaust ventilation systems are directly proportional to the flow rate of the ejected air. Consumption of the ejected air can be reduced by: reducing the speed of the falling bulk material flow; increase of aerodynamic drag when ejected air moves; organization of air circulation-recirculation. The aim of the article is to develop engineering methods of calculation of aspiration systems and shelters on the basis of previously obtained results of theoretical and experimental studies of the laws of ejected and recirculated air flow. The results and conclusions are as follows. The technique of engineering calculation of volumes of the aspirated air during reload of dry not heated materials with natural circulation, carried out by means of the combined use of the cylindrical bypass chamber and the perforated trough is developed. Experimental and numerical studies have shown that the proposed method has sufficient accuracy. Recommendations for the design of the developed aspiration shelter for more efficient operation with lower operating costs are proposed. The economic effect is to reduce energy intensity and the cost of cleaning dust emissions. The values are proposed for the recirculation coefficients for the calculation of the aspiration system using the bypass chamber and the combined use of the bypass chamber and the perforated trough. The method of calculation of the ejected air flow rate in telescopic loaders is developed. The high energy intensity of telescopic aspiration-technological units (ATU) of reloading stations is caused by the ejection ability of gravity flows of bulk material, pumping a large amount of air into the aspiration shelters, which significantly increases the required performance of aspiration systems. Power of ATU can be significantly reduced by the use of coaxial telescopic loading troughs and corrugated impervious wall surrounding the trough and sealing the top and bottom of the cover, adjacent to the troughs. The analytical flow rates estimation of air, moving inside the cavity of the "trough- bypass chamber", can be carried out by linearization of the dynamics and inter-component interaction equations with the subsequent solution of transcendent equations in the Maple universal mathematical environment. Numerical studies have shown that the main parameter for reducing the transit flow of ejected air and increasing the volume of recirculated air is the degree of sealing of the upper cover. For example, if the total area of the shelter leaks is reduced from 0.14 m2 to 0.02 m2, the flow of transit air will be reduced three times, and the recirculated air will be increased by 2.5 times. The total productivity of the local suction from the lower shelter in this case has decreased by 1.68 times
Experimental Evidence of Giant Electron - Gamma Bursts Generated by Extensive Atmospheric Showers in Thunderclouds
The existence of a new phenomena - giant electron-gamma bursts is
established. The bursts are generated in thunderclouds as a result of the
combined action of runaway breakdown and extensive atmosphere showers (RB-EAS).
The experiments were fulfilled at the Tien Shan Mountain Scientific Station
using EAS-Radio installation. This specially constructed installation consists
of a wide spread EAS trigger array and a high time resolution
radiointerferometer.Comment: 30 pages, 16 figure
Physical research of microgravity influence on physical phenomenon in cryogenic liquids and general-purpose onboard cryogenic facility for realization of this researchaboard International Space Station
The united research plan named "Boiling" is created on the basis of several cryogenic research projects developed by experts in Russia and Ukraine for International Space Station. The "Boiling" plan includes 8 first experiments aimed at investigating the influence of microgravity on boiling processes, heat transfer and hydrodynamics in liquid helium being either under normal or superfluid conditions. The experiments are supposed to be carried out with individual cells collected inside a single cryogenic onboard experimental facility. The international research program experiments are characterized by the following features: utilization of several artificially simulated microgravity levels, owing to rotation of the experimental helium cryostat; visualization of the processes that occur in liquid helium; research of boiling and hydrodynamics both in a large volume of stationary liquid, and in a liquid flow running through a channel. Upon completion of the "Boiling" research plan, the cryogenic onboard facility created for International Space Station would be able to find its application in further scientific and experimental researches with helium
Passive Q-switching and mode-locking for the generation of nanosecond to femtosecond pulses
The positions of foreign investors in the Russian oil and gas sektor: chaneged ecpectations
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84
Russia's energy situation - on problems of formation of interfuel competition: The 13th International Petroleum Tax Conference
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300
Analysis and Evaluation of Economic Condition of Energy Prospekt Implementation in the Yamalo-Nenets Autonomous Okrug
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143