摘要
以燃烧器四角切圆布置的超超临界塔式锅炉炉膛内的流动换热为背景,利用Fluent软件通过数值模拟研究了一个物理和几何结构完全对称的三维炉膛内冷态流场变化情况,选用6个燃烧器喷嘴出口速度作为不同的工况来计算炉内的流场,速度变化范围为5~30 m/s,湍流模型采用雷诺应力模型。计算结果表明,随着出口气流速度的增大,流动呈现出的切圆半径越来越大;当喷嘴出口速度小于等于10 m/s时,在所用计算模型下,流体速度场呈中心对称结构,切圆中心位于中央;随着出口速度的持续增加,流场从中心对称结构逐步转变成非中心对称结构,切圆中心发生明显偏斜.数值结果表明,即使几何结构完全对称且边界物理条件也完全对称的燃烧器四角切圆布置的炉膛中的流动,仍然可能是非对称的,这是造成烟气侧热偏差的可能的原因之一。
The 3D cold flow field is numerically simulated by Fluent software in the ultra-supercritical boiler furnace with four corner tangential symmetrical firing structure.Six cases of different burner outlet velocities are investigated by using Reynolds stress turbulent model(RSM) and the outlet velocity ranges from 5 to 30 m/s.The simulation results show that,by increasing the outlet velocity,the four corner tangential circle radius increase too;When the outlet velocity is less than or equal to 10 m/s,the cold flow field is central symmetrical,and when the outlet velocity further increases,through the threshold at which onset of non-symmetrical flow occurs within the boiler and the oblique tangential circle center is observed.The results also show that the flow within the boiler furnace with four corner tangential symmetrical firing structure may be asymmetric,that is the possible reason for thermal deviation of boiler furnace.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2014年第5期952-955,共4页
Journal of Engineering Thermophysics
基金
国家自然科学基金(No.51276118)
上海科技创新行动计划(No.12DZ1200100)
上海教委科研创新项目(No.14ZZ134)
关键词
锅炉
四角切圆
冷态流场
热偏差
数值模拟
boiler
four corner tangential firing
cold flow
thermal deviation
numerical simulation
