Propagation and Extinction of Mixtures of Air with n-Dodecane, JP-7, and JP-8 Jet Fuels

Abstract

Laminar flame speeds and extinction strain rates of fuels related to high-speed airbreathing propulsion were determined experimentally and numerically. Among practical jet fuels, JP-7 and JP-8 were investigated at fuel temperatures close to their boiling point. Mixtures of air with n-dodecane were investigated also because of the relevance of the latter to the development of jet fuels surrogates. The experimental data of n-dodecane were compared against numerical simulations obtained using a recently developed kinetic mechanism. The agreements between experimental and predicted values were good for both propagation and extinction, suggesting that the mechanism satisfactorily describes the heat release. It was found that the laminar flame speeds and extinction limits of n-dodecane is comparable to those obtained for both jet fuels, which underlines the significance of n-dodecane in the development of jet fuels surrogates. The effect of thermal cracking on flame propagation was studied also at fuel temperatures well above its boiling point, in view of its relevance to SCRAMJETs.