A CFD investigation of thermal hot spots in the ignition process of DEM based three-dimensional propellant beds

In this work, the resulting thermal hot spots in a propellant bed caused by the gas flow of the primer in a gun system are investigated. 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. The chemical reaction of the solid ignition charge is assumed to be completed and therefore the ignition is simplified by a hot gas flow without microparticles. With the given DEM-Output and the named assumption the heating of the particles by the gas flow emitted by the ignition charge is simulated using an Eulerian computational fluid dynamics (CFD) approach. Ansys Fluent is used to solve the conservation equations with heat transfer. Based on this model, the influence of the center core igniter on the uniformity of the resulting distribution of thermal hotspots as well as the resulting workflow is discussed.