REDUCTION OF LOSSES OF THE BULK MEDIUM PUMPED BY THE VORTEX CHAMBER EJECTOR BY USING A SLOTTED INTAKE NOZZLE

The problem of wear of mechanical moving elements of ejectors during the transportation of abrasive particles is relevant for many industries. Improving the reliability and durability of equipment for pumping solid abrasive media is possible by using jet pumps and ejectors. Particular attention should be paid to vortex chamber ejectors (VCE), the efficiency of which can be increased by reducing the loss of bulk media in the drainage channel through the use of a slotted intake nozzle. The mathematical modeling based on the numerical solution of the Reynolds-averaged Navier-Stokes equations was carried out, which made it possible to establish the dependence of the bulk medium losses on the operating parameters of the ejector. The SST (Shear Stress Transport) equations of the turbulence model and the continuity equation were added to the mathematical model. The developed mathematical models were confirmed by experimental studies that demonstrated their adequacy and practical applicability. The studies have shown that when using a slotted intake nozzle, the losses of bulk solid medium decrease with increasing the pumped medium density. For a cylindrical nozzle, minimal losses were observed in the density range of 2000–3000 kg/m³. Instead, the slotted nozzle provided lower losses with increasing medium density. The conditions for reducing the mass flow rate of solid particles in the drainage channel to zero were determined. Experimental studies have also shown that optimization of parameters such as the diameter and density of solid particles, as well as the total inlet pressure (flow swirl in the vortex chamber), can eliminate the loss of bulk solids in the drainage channel when using a slotted receiving nozzle. This ensures a significant increase in the energy efficiency of the VCE.