小尺度薄油池火沸腾燃烧特性研究

STUDY ON BOILING BURNING CHARACTERISTICS OF SMALL SCALE THIN LAYER POOL FIRES

通过对小尺度薄油池火燃烧特性进行实验研究,分析油池不同燃烧阶段的特点,探讨沸腾燃烧对油池燃烧特性的影响。测量了直径分别为0.10 m、0.14 m、0.20 m和0.30 m正庚烷油池火的燃烧速率以及温度分布随时间变化。分析燃烧过程中燃油液面温度和池壁温度的变化规律,研究池壁沸腾传热对油池沸腾燃烧的影响。结果表明:油池沸腾燃烧阶段的燃烧速率明显大于稳定燃烧阶段;燃油液面温度在油池燃烧初期迅速上升至沸点,随后基本保持不变;池壁温度达到并超过燃料的沸点,从而在油池壁面上发生沸腾现象,是油池发生沸腾燃烧的条件。

Burning characteristics of small scale thin layer n-heptane pool fires were experimentally studied.Burning rate and temperature distribution of pool fires with diameter of 0.10m,0.14 m, 0.20 m and 0.30 m were measured.The variations of fuel surface temperature and wall temperature in combustion process were analyzed,and the effect of boiling heat transfer on burning rate was investigated.Results show that the burning rate of boiling burning phase is obviously greater than that of steady burning phase.Fuel surface temperature rises to boiling point rapidly in the early stage of pool fire,and then remains almost unchanged.Once the wall temperature rises beyond the boiling point,boiling burning will occur.