Use of Condensed-Phase Reaction Models in Combustion Simulation of Energetic Materials

• Published in: Journal of propulsion and power 2008-03, Vol.24 (2), p.175-183
• Main Authors: Wang, Jun, Wight, Charles A
• Format: Article
• Language: English
• ISSN: 0748-4658; 1533-3876
• DOI: 10.2514/1.27312

The contribution of condensed-phase reaction kinetics to the overall combustion behavior of cyclotetramethylenetetranitramine is investigated in the context of a successful two-step chemical reaction scheme introduced by Ward, Son, and Brewster ("Role of Gas- and Condensed-Phase Kinetics in Burning Rate Control of Energetic Solids," Combustion Theory and Modelling, Vol. 2, No. 3, 1998, pp. 293-312; also "Steady Deflagration of HMX with Simple Kinetics: A Gas Phase Chain Reaction Model," Combustion and Flame, Vol. 114, Nos. 3-4, 1998, pp. 556-568). We derive extensions of the activation energy asymptotics of the condensed-phase reaction from nnth-order ( 0≤n≤10≤n≤1) kinetics to include 10 additional analytic reaction models. The results show that it is not possible to determine uniquely the condensed-phase reaction model by validating against steady-state burn rates and surface temperatures because the parameters of all models are sufficiently flexible to fit the experiments. However, the frequency-dependent transient response functions of mass burning rate to fluctuations in pressure and external radiation are somewhat more sensitive to the choice of kinetic model. The sensitivity of using different kinetic models to fit experimental T-burner data is more pronounced under conditions in which the surface temperature is low and no external radiation is applied. The power law model, which has the highest contribution to condensed-phase heat release, provides the best fit to transient combustion response functions. [PUBLISHER ABSTRACT]