Simulations of vented dust explosions in a 5 m3 vessel

Vented dust explosions were simulated using the computational fluid dynamics code FLACS-DustEx. The results were compared with previously reported experimental tests performed with maize starch in a 5.2 m(3) vessel with a length/diameter ratio equal to 1.05 using three different vent areas. In addition, a sensitivity study was conducted with respect to some of the parameters involved in the numerical simulations, including dust/air mixture reactivity, grid resolution and area size and activation pressure of the venting device. The simulation results were generally in good agreement with the experimental values, but the CFD code overpredicted explosion pressures for the scenario with the smallest vent area. The sensitivity analysis indicated that the results were dependent on both grid resolution and mixture reactivity. Further simulations confirmed the influence of the activation pressure of the venting device on the explosion overpressure when the vent area was large in comparison to the volume, i.e. with a low K-v (=V-2/3/A). These simulations made it possible to study scenarios outside the range of validity of current venting standards. (C) 2017 Elsevier B.V. All rights reserved.