Abstract:

To study the influence of initial temperature on the combustion behavior of pool fires, pool fire tests at different initial temperatures (5, 10, 20, 40, 60 and 80 ℃ ) were conducted using a self-built initial temperature controlled pool fire test platform. The characteristics of variations in combustion process, mass loss rate, flame height, and plume temperature were analyzed. The results show that when the initial temperature ranges from 5 to 60 ℃, the combustion process of oil pool fire is divided into three stages: growth, steady and decay. When the initial temperature increases to 80 ℃, the combustion process is divided into five stages: growth, steady, boiling transition, boiling and decay. The mass loss rate, flame height and plume temperature are all positively correlated with the initial temperature. When the initial temperature increases from 5 ℃ to 80 ℃, the mass loss rate, flame height and plume temperature increased by 12.13 g/(s·m²), 170.4 mm, and 130 ℃, respectively. The mass loss rate decreases nonlinearly with the temperature difference between the boiling point of n-heptane and the initial temperature. The ratio of flame height to pool diameter follows a power-law function of the ratio between the initial temperature and the boiling point of n-heptane point.

Key words: initial temperature, pool fire, combustion characteristics, burning process, mass loss rate, flame height, fire plume temperature