Burning rate, flame geometry and temperature of convection-controlled circular diesel oil pool fire under air crossflow conditions

Abstract

Hazardous fires in fuel storage tanks may result in casualties of great impact. Efforts are being done to master the physics of the phenomena, aiming both avoidance and damage minimization. Flame characterization is an important approach studied by many researchers. This article presents the results of an experimental investigation of diesel oil (S500 type) pool fires under air crossflow conditions. A reduced scale model properly instrumented was tested in an aerodynamic channel. Measurement techniques include analysis of infrared images of pool fires, mass burning rates and flame geometry as a function of air crossflow velocity (which ranged from 0 m/s - quiescent air - to 4.0 m/s). Mass burning rates showed an oscillatory behavior as the crossflow velocity was raised. Regarding flame geometry, for an increasing air crossflow, firstly flame tilt angle increased, flame length decreased and flame height decreased until about 1.5-2.0 m/s, while after that velocity, flame geometry became nearly steady. Geometry results were also compared with thirteen correlations from literature for geometric parameters obtaining good agreement for some of them. The IR-measured temperatures showed that the flame region (reacting region) became hotter and the plume region (non-reacting region) became colder as the air crossflow velocity was increased.

Keywords: Air crossflow.; Burning rate; Diesel oil; Flame geometry; Pool fire.