Multidimensional Numerical Simulation of Ammonium-Perchlorate-Based Propellant Combustion with Fine/Ultrafine Aluminum

This paper presents a computational investigation on the deflagration of composite ammonium-perchlorate-based propellant with fine/ultrafine aluminum. The model relies on an Eulerian representation of the particle cloud formed by the ejected aluminum and a gray-medium approximation of the radiative field supported by the emitting particles. The aluminum oxidation is modeled by means of an experimentally evaluated diameter power law valid for constant-ambient conditions. The energetic consequences of the addition of nanoscale aluminum are analyzed, with particular emphasis on the contributions of radiative transport and aluminum oxidation heat release. The model is validated versus experimental measurements of burn rates for both one-dimensionally (fine ammonium perchlorate) and three-dimensionally (monomodal and bimodal coarse ammonium perchlorate) supported combustion fields. The burn rate and surface shape of two-dimensional laminate propellant is also considered, and the particle consumption time is related to experimental observations.