Experimental Study of Aluminum Flame Propagation in Duct with Obstacles

To accurately model the consequences of accidental dust explosions, numerical simulations of the flame propagation process are required. A key parameter in these models is the burning velocity ( ?? ?? ), which represents the consumption rate of the reactants by the flame front. Experiments are therefore needed to determine the burning velocity, and the influence of turbulence on this velocity; as well as to validate these models of flame propagation. In this article, aluminum flame propagation inside a vertical duct with obstacles is studied. The aim of the obstacles is first to increase the turbulence just in front of the flame front, in order to quantify its influence on the burning velocity. The second objective of the implementation of the obstacles is to obtain experimental data in a more complex geometry in order to validate the models. During these experiments, the flame propagation is recorded and the unburned flow velocity is measured using the TR-PIV (Time-Resolved Particle Image Velocimetry) technique. This innovative measurement of the unburned flow velocity is important not only for the accurate determination of the burning velocity, but also to validate these numerical simulations. An increase in the propagation velocity and the burning velocity is observed as the flame propagates toward the obstacles.