Уточнение методов расчета грузопотоков конвейерных транспортных систем угольных шахт

Abstract

Productivity of a mining enterprise is limited by the possibility of its transportation subsystem, which efficiency improvement is an urgent scientific and practical task. Studying the processes of formation and transformation of material flows allows us to clarify the design methodology of continuous haulage systems. The normative methodology of belt conveyors selection is based on treating the material flows as normally distributed random variables, with the point value, i.e. the irregularity coefficient, being used as the main indicator. There are doubts in methodological justification of such an approach. The normal law of distribution in the classical variant adequately describes a random variable changing within infinite limits, and real mine material flows via the conveyor lines are random variables with unilateral constraints. The majority of tasks on finding the design ranges of material flows can be solved using experimentally established distribution functions (or probability density functions) of random quantities of material flows. Based on the publications in recent years, as well as on our own experimental studies, it is proposed to describe material flows by piecewise linear probability density functions, in particular the triangular ones, and to summarize material flows on the basis of general theoretical provisions of classical probability theory. The paper solves a particular problem of finding an analytical solution of the sum of two random material flows defined by the triangular distribution laws and compares the results of numerical integration of the probability densities of the material flows.