Experimental Study of Temperature Distribution and Flame Spread Over an Inert Porous Bed Wetted with Liquid Fuel

Abstract

A combined experimental and modelling study was carried out to investigate the flame spread phenomenon over a porous bed wetted with finite quantity of super-flash liquid fuel. Measurements included flame spread rate, temperature distribution, and visual observation. Sand particles ranging from 0.5 to 5 mm and Propanol (flash point 12 °C) were used as porous bed and liquid fuel, respectively.Results corresponding to the rate of flame spread show that regardless of airflow speed and/or direction the rate of flame spread decreases as either the bed depth or particle size increases, however the flame spread deceleration rate is more distinct under opposed airflow.Temperature measurements and mathematical modelling results indicated the existences of three different temperature regions in the bed. The magnitude of temperature in upper region was significantly larger than those of the lower region. The modelling results were in good agreement with the experimental data.

Effect of fuel soaked time and fuel ratio on the flame spread rate over a porous bed wetted with liquid fuel

“…While there are many papers on pool fires for example [1][2][3][4] and flame spread over porous bed flushed-up with liquid fuel [5][6][7][8][9][10][11][12][13][14][15], the rate of flame spread and flame behaviour over a bed soaked with a finite amount of liquid fuel is still unexplored. Despite the importance of the subject there are only a limited number of studies are available about the flame spread over porous beds wetted with finite quantity of liquid fuel in the open literature [16][17][18][19][20][21][22][23].…”

“…Results obtained from these investigations revealed that the flame spread rate under both assisted and opposed airflow configurations noticeably decreased as the air speed was increased although the extent of decay in the flame spread rate was more pronounced in the case of the opposed airflow configuration [18,21]. However, regardless of airflow speed and/or direction the rate of flame spread was found to decrease as either the bed depth or particle size are increased [20]. Moreover, the investigation revealed that the fuel penetration rate into the porous bed was a function of bed permeability and the mass of the liquid fuel.…”

“…The present study builds upon our previous investigations [16][17][18][19][20][21][22][23] specifically aims at examining the effect of fuel ratio (FR) and flame initiation delay (FID) on the rate of flame spread over a solid porous bed wetted with a limited quantity of liquid fuel. To achieve the broad objectives of the study a comprehensive series of combined experiments and theoretical investigations were carried out.…”

Experimental and mathematical analysis of fuel penetration through unconsolidated porous media

“…Although there are a large number of comprehensive studies on the subject of flame spread over porous beds , the rate of fuel penetration through the porous bed and consequently the impact of this phenomenon on the rate of flame spread in scenarios of accidental fuel spillage are not well understood. The current study is an attempt to shed some light on this unknown subject.…”