插入铝板对小尺寸油罐火燃烧行为的模拟分析

Simulation Analysis of Small-Scale Oil Tank Fire Behavior with Embedded Aluminum Plates

利用FDS软件对正庚烷油罐火在插入不同高度铝板情况下的燃烧行为进行研究.发现火焰高度随铝板高度先增后减;通过核态沸腾对流传热公式对FDS燃烧速率结果进行修正,修正后的插板燃烧速率大于无插板时.在无量纲铝板高度为2.5~3.0时插板对燃烧的增强作用最大,这一非单调变化主要是两个效应博弈的结果:一是铝板通过热传导将火焰热量反馈给燃料,二是铝板吸收火焰热量后对外的辐射和对流散热.

The combustion behavior of n-heptane tank fire with embedded aluminum plates of different heights was studied using software fire dynamic simulation(FDS).It was found that the flame height first increased and then decreased with the height of the aluminum plate.The simulated burning rate was corrected by the convection heat transfer formula at nucleate boiling.The corrected burning rate with embedded plates was larger than that without.When the dimensionless aluminum plate height was 2.5-3.0,the enhancement effect of embedded plates on combustion was the maximum.This non-monotonic change was mainly the result of two effects:the first was the heat feedback from the aluminum plates to the fuel through heat conduction,and the second was the radiative and convective heat loss of the aluminum plates to the ambient environment after they had absorbed the flame heat.