90°弯曲管道对丙烷-空气预混火焰传播的影响  

Influence of 90° Bend on Propane-Air Premixed Flame Propagation

作　　者：何学超[1,2] 孙金华[1] 丁以斌[1] 尹艺[1] 袁国杰[3] 

机构地区：[1]中国科学技术大学火灾科学国家重点实验室,合肥230027 [2]中国科学技术大学苏州研究院,苏州215123 [3]香港城市大学建筑系,香港999077

出　　处：《燃烧科学与技术》2010年第3期241-245,共5页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(50976110)

摘　　要：为了揭示90°弯曲管道结构对预混火焰传播特性的影响,以丙烷-空气预混火焰为研究对象,运用高速纹影摄像、微细热电偶以及离子探针等测试手段对火焰在90°弯曲管道内的传播过程进行了实验研究.结果表明,预混火焰结构在水平管道内发生了明显变化,由规则的球形层流火焰转变为具有轴对称结构向内凹陷的湍流火焰,并伴随火焰阵面的皱褶分层.火焰进入90°弯曲管道后,受几何形状影响,火焰阵面发生畸变,对称结构被破坏,下壁面处的火焰阵面逐渐超过上壁面处的火焰阵面.由于弯管内部多波叠加作用以及湍流的影响最终使得火焰速度呈现脉动振荡.To reveal the influence of 90°bend on premixed flame propagation behaviort,he premixed propane-air flame was experimentally investigated in a curved pipe.The high speed schlieren image systemf,ine thermocouples and ion current probes were used to explore flame structure and propagation characteristics.The results show that the premixed flame structure has been significantly changed in the horizontal partf,rom a regular spherical laminar flame to an axisymmetric turbulent flamea,ccompanied by flame wrinkles and stratification.Due to the complicated geome-tric configuration of the 90°bendt,he flame front is distorted and the axisymmetric structure is destroyed.Finallyt,he flame front at the lower side exceeds that at the upper side.Meanwhile,multiwave and turbulence effects induce flame velocity pulsative oscillation in the bend.

关 键 词：预混火焰 90°弯管 火焰结构 湍流燃烧 

分 类 号：TK401[动力工程及工程热物理—动力机械及工程]