A CFD Investigation of Thermal Hot Spots in the Ignition Process of DEM Based Three Dimensional Propellant Beds

In this work, we investigate the resulting thermal hot spots in a propellant bed caused by the gas flow of the ignition charge in a gun system. In this process the distribution of the propellant bed is simulated by a three-dimensional discrete element method (DEM) in a generic ammunition case using the DEM-software RockyDEM. We assume, that the chemical reaction of the solid ignition charge is completed and therefore simplify the ignition by a hot gas flow without microparticles. With the given DEM-Output and the named assumption we simulate the heating of the particles by the gas flow emitted by the ignition charge using an Eulerian computational fluid dynamics (CFD) approach. Ansys Fluent is used to solve the conservation equations with heat transfer. Based on this model, we discuss the influence of the igniter tube on the uniformity of the resulting distribution of thermal hotspots as well as the resulting workflow.