Modeling of a reacting nanofilm on a composite substrate

This article provides a detailed computational analysis of the reaction of dense nanofilms and the heat transfer characteristics on a composite substrate. Although traditional energetic compounds based on organic materials have similar energy per unit weight, non-organic material in nanofilm configuration offers much higher energy density and higher flame speed. The reaction of a multilayer thin film of aluminum and copper oxide has been studied by varying the substrate material and thicknesses. The numerical analysis of the thermal transport of the reacting film deposited on the substrate combined a hybrid approach in which a traditional two-dimensional black box theory was used in conjunction with the sandwich model to estimate the appropriate heat flux on the substrate accounting for the heat loss to the surroundings. A procedure to estimate this heat flux using stoichiometric calculations is provided. This work highlights two important findings. One is that there is very little difference in the temperature profiles between a single substrate of silica and a composite substrate of silicon–silica. Secondly, with increase in substrate thickness, the quenching effect is progressively diminished at a given speed. These findings show that the composite substrate is effective and that the average speed and quenching of flames depend on the thickness of the silica substrate, and can be controlled by a careful choice of the substrate configuration.

Research highlights► Nanocomposites are widely used in different applications like thermal storage and more importantly as Metastable Intermolecular Composite for energy production. ► Nanoscaling can improve the reactivity. The energy density and the flame speed are the key variables that characterize energetic material. ► The objective of this paper is to determine the sustainability of the dense nanofilm reaction for different flame speeds and composite substrate thicknesses. ► The numerical analysis of the thermal transport of the reacting film combined a hybrid approach (black box theory with sandwich model) using experimentally determined flame speed. ► The paper shows that the flame speed and quenching can be controlled by a careful choice of the substrate configuration.