The Effect of Ambient Conditions on the Burning Rate of Gel Fuel Droplets

An experimental study was conducted to determine the dependence of the burning rate coefficient of gel fuel droplets on the pressure at different ambient oxygennitrogen mixtures. Experiments were conducted using a pressure chamber, in which the droplet was suspended and the combustion process was video-photographed by a high-speed digital video camera. The tests were conducted at pressures between 0.14MPa at different ambient oxygennitrogen compositions (air, 40% O2 60% N2, and 60% O2 40% N2). The fuel was a compound of 95% kerosene and 5% gellant. At sub-critical pressure conditions, the burning rate coefficient was found to increase with increasing ambient oxygen mass fraction. At supercritical conditions, no dependence of the burning rate coefficient on the ambient mixture was found. The results indicate that the burning rate coefficient depends on the oxygen partial pressure, at least at low pressures.