摘要
在内尺寸为1m(长)×1m(宽)×0.75m(高)的无开口封闭空间进行了庚烷池火燃烧实验,重点研究了封闭空间内庚烷池火火焰的振荡行为特性,油池尺寸包括0.100,0.141,0.200和0.300m四种规格.实验发现,火焰根部面积的变化频率与火焰高度的振荡频率相等,在此基础提出了采用火焰根部面积的变化频率求取火焰振荡频率的方法,并应用于具有顶棚射流的封闭空间池火火焰振荡频率的确定.研究结果表明,在燃烧过程中油池火焰振荡频率波动较小,火焰振荡频率小于开放空间经验公式预测值,火焰振荡频率与油池直径的关系拟合结果为f=1.33D-0.5,且对无量纲关系式St=0.26Fr-0.532符合较好.
A series of experiments on heptane pool fires were conducted in a closed compartment without vents with the inner dimensions of 1 m（L）×1 m（W）×0.75 m（H）,focusing on flame pulsation characteristics.Different pools with the diameters of 0.100,0.141,0.200 and 0.300 m were investigated.Based on the fact that pulsation frequency of flame bottom area equals that of flame height,a method using flame bottom area was proposed to determine flame pulsation frequency and applied to pool fires in closed compartments with ceiling jet flames.The results show that the variation of flame pulsation frequency is small,and the flame pulsation frequency is smaller than those predicted by empirical equations developed for burnings in free atmosphere while it fits well with the scaling relationship St=0.26 Fr-0.532,and the expression of f=1.33D-0.5 is appropriate in describing the relationship between the flame pulsation frequency and pool diameter.
基金
国家自然科学基金(50976109)
"2008年度中国科学院研究生科技创新与社会实践资助专项"资助
关键词
油池火
封闭空间
火焰振荡
pool fire
closed compartment
flame pulsation
