Flame and burning dynamics of pool fire inside semi-confined compartment under external cross wind

Abstract

In this paper, experimental and theoretical studies of the flame shape and burning rate of pool fire inside a semi-confined compartment (with one sidewall and ceiling open) under the cross wind were investigated. The effects of fuel pool size and cross wind velocity on the flame morphological parameters and burning rate were obtained. Three typical bending behavior of the tilted flame was observed during the experiments. The dimensionless burning rate m˙″* decreased slightly when Frw<1, and increased linearly with Frw when Frw≥1. An air gap (δair) between the flame and sidewall was observed because of the restriction of the sidewall and blow-off by strong airflow recirculation. Theoretical analysis of wind-blown pool fire inside the semi-confined compartment was conducted based on the asymmetrical air entrainment and the buoyancy length scale. A dimensionless parameter (sm˙fρ∞uwlb2) considering the burning rate and cross wind velocity was proposed to predict the flame height, flame tilted angle and air gap thickness. The flame morphological characteristic parameters and the thickness of the air gap were correlated linearly well with the dimensionless parameter in exponent expression.