(续上期 )5　露天火灾的行为　　最简单的火灾是露天条件下的火灾 ,它既不受墙壁的影响 ,也不受顶棚的影响。露天的火灾被视为自由燃烧的火灾 ,一般是受燃料控制的。在这种火灾的正上方 ,炽热气体和燃烧产物的气流柱可升至空气之中。该气流柱称之为羽流 ,它形成一个倒锥形柱体 (Continued) 5 Behavior of Open Fires The simplest fires are open-air fires that are neither affected by the walls nor by the ceiling. Open fires are considered as free-burning fires and are generally fuel-controlled. Directly above this fire, the gas column of hot gases and products of combustion rises into the air. This gas flow column is called a plume and forms an inverted conical cylinder