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The schemes of aspiration of elevator overloads have been developing. Balance equations of ventilation of aspiration covers are compiled. The system of equations for determination of the volumes of ventilating air for a standard node overload are formulated and solved. Ways of reducing productivity of aspiration systems are offered and analytically substantiated. Three bypass channels can be used to reduce aspiration volumes in elevator handling facilities by maintaining a smaller negative pressure inside unaspirated cowls of the elevator feeder and head. Airflows can be quantitatively decomposed using combined equations describing pressure losses in loops of a proposed aerodynamic equivalent for the assembly. These combined non-linear equations have been solved numerically using a specially developed algorithm based upon joint application of iterative and bisection procedures. Analysis of the findings for a “standard” elevator indicates that reduction in flow rates of air entering through leakage areas of unaspirated cowls is maximized when two bypass connections are installed: the lower one, connecting feeder cowl with a buffer chamber upstream of elevator boot cowl, and the upper one, connecting elevator head cowl with the inner chamber of a double-walled cowl of the upper (receiving) conveyor. The total flow rate in the case reviewed was 1.37 times lower than (a corresponding aspiration case with identical process and design parameters of the assembly, but with no bypass ducts). The effect cited may differ from the actual effect in every particular case. The computer program developed for the purpose can be used to provide a design-stage estimate.

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 requir

The paper outlines the developed mathematical models, computational algorithms forcalculation of dust and gas streams in the spectrum of action of local ventilation device of the closed type (aspiration shelter) from nodes overload of granular materials.

To ensure the complete localization of dust emissions, arising from the formation the overpressure in shelters, when heated conveyor overload materials is usually performed through suction of air from two shelters - from the upper (the upper shelter of the drive drum conveyor) and the lower (the lower shelter is place of loading the conveyor.) The main problem when designing of aspiration systems such congestions is to determine the required flow of air, sucked out of the shelters. We have developed a scientifically based method [1,2] which allows us not only to determine the required flow of air, removed from the shelter, but also to choose the rational allocation schemes of aspirating pipes, which is especially important in the cascade arrangement of equipment (feeder -rumble - crusher - conveyor), which covers are linked. The solution of this problem have been achieved in the use of the correct model of dual-velocity continuum "particulate matter - the air", which allowed at a modern level to estimate the dynamic interaction of the flow of air particles under overload of bulk material, as a free running particle jets, and as it moves through a closed overload troughs. The existence of combinations of these regimes is characterized by almost all industrial overload nodes. Intercomponent heat transfer modifies the picture of air movement in these nodes, which we have been examined in the gravitational movement of the particle flux in an inclined chute. The developed procedures of calculation of performance aspiration systems have proliferated in Russia and abroad in the mining and metallurgical industries.