Effect of Pressure on the Heat Transfer of Pool Fire in a Closed Chamber
Jian Chen, Yubo Bi, Yanli Zhao, Wai Cheong Tam, Changhai Li, Shouxiang Lu
A combined analytical and experimental study was performed to determine the effect of pressure on the heat transfer of pool fire in a closed chamber. A series of ethanol pool fires with diameters from 4 cm to 10 cm were carried out in the pressure chamber with interior dimensions of 0.6 m (Height) × 0.4 m (Diameter), where the different initial pressures were ranged from 0.6 atm to 2.5 atm. Considering the effect of pressure, a theoretical formulation was proposed to estimate the radiation flux received by the fuel surface from the chamber surface and hot gases, with which the relationship between the modified burning rate of pool fire and pressure was obtained. It is found that external radiation received by fuel pool is affected by the gas emissivity, the gas transmissivity, the gas temperature and the wall temperature, and these factors compete with each other in determining the effect of pressure on the magnitude of external radiation. Furthermore, the average burning rate modified by the obtained external radiation was fitted with pressure by a power function, and the fitted exponent value was found to be consistent with theoretical analysis.
Journal of Thermal Analysis and Calorimetry
Pool fire, Pressure effect, Closed chamber, Heat transfer