Numerical Simulation of the Basalt Melt Flow Through the Feeder Tray of Gas-Electric Furnace

The quality of the mineral wool obtained from basalt melt depends on stable mass flow rate and slug properties. Basalt slag supplies from gas- electric furnace to centrifuge through the “feeder tray”, that uses to stabilize the slag flow, decrease flow rate fluctuations and maintain the required temperature. In this work we used CFD (Computational Fluid Dynamics) methods (within the ANSYS Fluent program) to estimate the feeder efficiency. The practice of numerical simulations of industrial processes shows that these methods allow evaluating the operation of equipment without making expensive and long experiments. We found that the base feeder design is efficient enough in decreasing of short period pulsation (about 1 sec), but this feeder fails to mitigate long period pulsations (more than 100 sec). The analysis of the melt velocity field showed that the maximum pulsation of velocity occurs in the upper part of the flow. The velocities in the lower part of the melt practically do not change when the melt flow rate changes. The simulation showed that an increase in the size of the feeder (its height) does not significantly affect the stabilization of the output flow with rapid fluctuations in the output flow characteristic of a gas- electric cupola (in the same amplitude range). A modification of the base design was proposed and numerically simulated. We suggested incorporating a baffle in the center of the feeder tray. The baffle increases the efficiency of pulsation damper both for short-period and long- period fluctuations. To reduce stagnant zones and heat loss, we propose to use inclined slag melt flow into the tray, i.e. use skew brick instead of usual.