Существующие методы определения эффективной мощности, основанные на расчете средней индикаторной работы двигателя за рабочий ход поршня, не учитывают при движении изменение термодинамических параметров и политропную работу двигателя, значение которой зависит от политропного КПД рабочего цикла. Это является причиной того, что расчет эффективной мощности приводит к некоторой погрешностизапасу особенности двигателя. Выявление этого запаса позволяет пересмотреть всю линейку карьерных самосвалов в сторону увеличения их паспортной эффективной мощности, что приведет к снижению капитальных затрат на закупку благодаря выбору ранее недооцененного и более дешевого варианта, а также снижению текущих издержек деятельности из-за снижения степени удельного расхода топлива. Учет стохастического характера транспортного процесса и оценка влияния всех внешних и внутренних факторов при расчете рационального режима работы карьерного самосвала позволяют дополнительно снизить удельный расход топлива с помощью выбора рациональной скорости его движения в груженом и порожнем направлениях. Ключевые слова: эффективная мощность; тягово-скоростные характеристики; политропный КПД; удельный расход топлива; скорость движения автосамосвала Как цитировать эту статью: Александров В.И. Эффективная мощность и скорость движения карьерных автосамосвалов в режиме топливной экономичности / В.И.Александров, М.А.Васильева, В.Ю.Коптев //

The issue of the influence of the concentration of the solid phase on the reduction of energy costs and specific energy consumption during pulp transportation is considered. The procedure for preparing slurry from the current enrichment tailings is shown. A scheme is given and the operation of a hydroficated unit for thickening and hydraulic transport of backfill mixtures is described. A diagram of the movement of solid particles in one of the units of the complex – a lamellar thickener is shown. The summary table shows the main design parameters and characteristics of the lamellar thickener. A general view of the laboratory setup used for experimental studies with slurry at various concentrations is given. An example of calculating productivity, density and specific load is presented. The dependence of the shear stress on the velocity gradient was determined for various pulp concentrations. Experimental studies of the process of thickening the production of slurry from the current enrichment tailings have been carried out. It was found that the geometric dimensions of the thickener depend on the concentration of the solid phase in the transported mixture. It is concluded that the flow rate of the slurry and the head loss are functions of the rheological characteristics of the viscoplastic slurry and can be calculated from the derived calculated dependencies.

The article is devoted to the analysis of the composition and properties of the materials and liquids during transportation using pipeline and shows that in order to increase the efficiency of hydraulic transport systems in mining a transition to the transportation of slurries with a high concentration of solids in the slurry flow is necessary. Experimental studies have shown that slurry tailings of gold-containing ore with mass concentrations of more than 55 % are viscoplastic fluids. Experiments on a rotational viscometer allowed us to establish the main rheological characteristics of the studied slurries – shear stress and the dynamic effective viscosity. It has been established that over the entire range of concentrations from 55 to 65 %, the flow of slurries is described by the Bingham rheological equation. Experimental studies of hydraulic transport performed on a laboratory setup with a pipeline diameter of 50 mm confirmed the results obtained on a rotational viscometer. The curved of mixture stream is inclined straight lines that are cut off on the axis of the head in the sections, which determine the initial hydraulic slope corresponding to the yield shear stress on the rheological curves. According to the results of the experiments, a method has been developed for calculating the hydraulic transport of high concentrated slurries of tailings of gold-bearing ore. Calculations showed that in a given range the performance of the hydrotransport system and the mass concentration of the solid phase pressure losses vary from 11 to 84 m of water column/m. Head loss values increase with the increasing concentration. A sharp increase in the head loss occurs in the concentration range from 60 to 65 % and higher.

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