MODELLING AND SIMULATION OF FREE-FLOWING MATERIAL WEIGHING IN WEIGH HOPPER

Abstract

Topicality. Necessity of reducing ships’ downtime during grain transshipment from port elevators requires intensification of handling operations. It can be provided not only by using transport mechanisms of greater capacity, but also by threadtransport lines operations automation, which will eliminate possible human operator errors. Creation of automatic control systems, in turn, requires development of mathematical and simulation models of thread-transport lines, an integral part of which are weigh hoppers of periodic action. Objective. To create simulation model of weigh hopper operation, which reflects its properties as a control object. Method. Known differential and algebraic equations of weighing in weigh hopper are used. They include influence grain weight on its mechanical system as well as dynamic force which grain creates during falling. Simulation models for MatLab/Simulink were created on the basis of these equations. Results. Computer experiments with weigh hopper models which include simulation of different operating conditions were planned and carried out. Trends were obtained, which define effectiveness of its operation. Conclusions. Effectiveness of weighing process is defined by optimal combination of weigh hopper productivity and its dynamic inaccuracy. To increase productivity weighing cycle must be reduced. However, this reduction is limited by time, which is necessary for damping of mechanical system oscillations.

Keywords

• weigh hopper of periodic operation
• simulation model