Investigation on micro-flame structure of ammonium perchlorate composite propellant under wide pressure range

Abstract

This present work proposes a method to exactly evaluate the thermal process of ammonium perchlorate/hydroxyl-terminated polybutadiene propellant. The 3-D propellant pack is generated by the Monte-Carlo method to obtain a representative sandwich model on the base of the dual-slicing technique. The ammonium perchlorate monopropellant flame height H1, the primary diffusion flame height H2, and the final diffusion flame height H3 are jointly determined by the temperature and component distributions of the gas phase thermodynamic field, which is more accurate to capture this complicated combustion field distribution of the gas phase comparing with earlier reported studies. Peclet number and Damkohler number are also introduced to quantitatively investigate the influence mechanism of chemical kinetics and diffusion mixing process of components on this micro-flame structure under wide pressure range (0.69-20.7 MPa). Further, based on the criterion of whether the premixed flow above the burning surface can absorb heat flux continuously from the diffusion flame to approach adiabatic flame temperature, the diffusion flame is divided into two regions in detail: flame front and trailing diffusion flame.