The project studies iron particle cloud ignition and combustion in homogeneous isotropic turbulence (HIT) with direct numerical simulation (DNS). This is a part of the Clean Circles project, involving scientists from multiple disciplines to explore how iron and its oxides can be used in a cycle as a carbon-free energy carrier. Metal fuels are a promising concept for storing large amounts of energy. Solar or wind energy can be used to reduce pulverized iron oxide particles to pure iron, which can be burnt in retrofitted coal power plants. The iron oxides resulting from combustion can be reused, keeping the metal fuels in the system. The combustion process of iron differs from common biomass or coal oxidation, since the metal particles typically react heterogeneously and no volatile combustion occurs.

The goal of this subproject is the characterization of the turbulence-combustion interaction. When iron particles are exposed to turbulent flow conditions, they may cluster, which affects particle ignition and combustion. The DNS will shed light on the fundamental processes that govern ignition and combustion of iron particle clouds, to establish models which can later be used for industrial burner design.