Experimental research and computer modeling of the obstruction occurrence in the pneumatic conveying systems peculiarities

Abstract

At designing new and modernizing existing pneumatic transport systems it is necessary to take into account changes in the electromechanical parameters of the equipment during start-up or other transient conditions that are most dangerous from the point of view of the occurrence of a blockage in the pneumatic system. Given the high cost of electricity and large volumes of production during the transportation of bulk materials, the urgent task is to reduce the specific consumption of compressed air during transportation, taking into account the development of automatic control systems for the main factors, namely, pressure loss at the outlet of the pneumatic system, affecting the occurrence of blockages of pneumatic conveying systems. The aim of the work is to conduct experimental studies and computer modeling of the features of blockage in pneumatic conveying systems during transportation of bulk materials associated with pressure loss at the outlet of the pneumatic transport systems. This goal is achieved by conducting experiments, on the basis of which an analytical expression is obtained to determine the speed of the mixture, which provides the minimum admissible pressure at the outlet of the air bag by the technological process. An analytical dependence of the occurrence of a possible clogging point on the pressure drop at the outlet of the air duct is obtained, which determines the minimum step of the impact on the transported two-phase flow in order to prevent the occurrence of blockages, and also, if necessary, indicates the place of occurrence of the blockage. It was established that with increasing pressure difference at the inlet and outlet of the pipeline, the point of possible blockage shifts towards the chamber feeder. Stabilization of the humidity of the compressed air supplied to the pneumatic line through the use of more sensitive and faster measuring equipment and automated control means will reduce the possibility of blockage, save energy, and therefore increase the efficiency of the pneumatic conveying system. Mathematical and computer models of the electric drive of the pneumatic transport system have been developed; graphs of electromechanical processes have been obtained, confirming its adequacy with an accuracy of ten-twelve percent for steady regime. Using these models will save time and money on conducting preliminary experiments in the development of new and modernization of existing pneumatic transport systems.