Effect of flame radiation on aluminium particle combustion time

Abstract

This work proposes a numerical model to estimate the radiant heat feedback from the flame of a burning aluminium particle. The objective is to evaluate its role on the burning time. It rests on a detailed combustion simulation of a single particle coupled with a simple two-flux approximation for the radiant flux emitted from the oxide smoke. Radiated flux from the flame is found to be around 1 MW/m${}^2$ for atmospheric pressures, going up to more than 5 MW/m${}^2$ for higher pressures (30 bar). Parametric simulations show that aluminium size has a small effect while oxygen-rich atmospheres can double the radiated flux. Overall, the role of flame radiation on aluminium burning rate is calculated to lie roughly between 1 and 25%, depending on conditions. This is the first study that clearly evaluates the role of flame radiation on aluminium combustion ; in most configurations, this effect, however, remains limited.

Keywords:

• aluminum combustion
• radiation
• solid propulsion
• aluminium oxide

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was funded by the French Defense Procurement Agency (DGA). The authors warmly thank Hugo Keck (University of Orléans) for providing us with his Mie theory code.