| A computational study has been conducted for high-speed reacting flows relevant to munition problems, including shock-induced combustion and gun muzzle blast. The theoretical model considers inviscid and viscous flows, multi-species, finite rate chemical reaction schemes, and turbulence. Both the physical and numerical aspects are investigated to determine their impact on simulation accuracy.; A range of hydrogen and oxygen reaction mechanisms are evaluated for the shock-induced combustion flow scenario. Characteristics of the mechanisms such as the induction time, heat release rate, and second explosion limit are found to impact the accuracy of the computation. On the numerical side, reaction source term treatments, including logarithmic weighting and scaling modifications, are investigated to determine their effectiveness in addressing numerical errors caused by disparate length scales between chemical reactions and fluid dynamics. It is demonstrated that these techniques can enhance solution accuracy.; Computations of shock-induced combustion have also been performed using a {dollar}kappa{dollar}-{dollar}varepsilon{dollar} model to account for the turbulent transport of species and heat. An algebraic model of the temperature fluctuations has been used to estimate the impact of the turbulent effect on the chemical reaction source terms. The turbulence effects when represented with the current models are found to be minimal in the shock-induced combustion flow investigated in the present work.; For the gun system simulations, computations for both a large caliber howitzer and small caliber firearms are carried out. A reduced kinetic scheme and an algebraic turbulence model are employed. The present approach, which accounts for the chemical reaction aspects of the gun muzzle blast problem, is found to improve the prediction of peak overpressures and can capture the effects produced by small caliber firearm sound suppressors.; The present study has established the numerical and physical requirements for simulating high-speed reacting flows. Also, key parameters useful in quantifying the roles of these aspects have been assessed. |
