300MW四角切圆锅炉二次风风箱结构优化数值模拟

Numerical Simulation of Optimized Structure of Secondary Air Bellows in 300MW Corner Tangential Fired Boiler

采用计算流体力学软件对某300MW四角切圆锅炉机组二次风风箱流场进行分析,以湍动能和出口速度分布均匀性为指标对风箱结构进行数值研究。结果表明:设置有组合导叶、风箱倒角和蜂窝器的方案有助于减少湍流,增加二次风刚性,保证切圆直径处于中心位置。改进后的结构出口速度均匀性为原设计的4.6倍,切圆直径与理论值相近。

Through making use of CFD software,the flow field of the secondary air bellows in a 300 MW corner tangential boiler was analyzed and both turbulence energy and exit velocity uniformity were taken to investigate the bellows' structure to show that,the structure which boasting of the combined guide vanes,chamber and honeycombs can reduce the turbulence and increase the rigidity of secondary air and ensure the circle diameter in the center. The exit velocity uniformity of bellows improved is 4. 6 times that of the former design and the circle diameter is close to the theoretical value.