600MW直接空冷汽轮机组排汽装置流场数值模拟和结构改进  

Numerical Simulation of Flow in the Exhaust Steam Device and Structure Modification for a 600MW Direct Air-cooled Unit

作　　者：刘艳[1] 姜沃函[1] 董建华[2] 姜晓霞[2] 赵鹏飞[1] 

机构地区：[1]大连理工大学能源与动力学院,大连116024 [2]哈尔滨汽轮机厂辅机工程有限公司,哈尔滨150046

出　　处：《汽轮机技术》2011年第5期339-341,368,共4页Turbine Technology

摘　　要：应用雷诺平均的Navier-Stokes方程对600MW直接空冷机组排汽装置的内部流场和气动性能进行数值研究。湍流模型使用标准的k-ε两方程模型。计算结果表明原结构90°直角转弯不合理。基于此,提出了两种改进方案。一是将90°直角转弯改成90°圆弧转弯;二是在内部加导流板。模拟结果显示结构改进后转弯附近的流场比原结构流畅且流动无分离发生,流场得到了改善。额定工况和小流量工况下,两种改进结构的进出口总压和静压损失系数比原结构均降低6%以上。说明结构改进后的排汽装置气动性能得到了改善。Reynolds averaged Navier-Stokes equations are applied to numerically study flow field and aerodynamic performances of the exhaust steam device of 600MW direct air-cooled unit. The turbulence model employed is the standard κ -ε two-equation model. Results show that the original turning with 90 degree right angle is not satisfactory. Based on this result, two modifications to the original geometry are proposed in this study. One is to make the turning with 90 degree circular angle. The other is to place flow guiding plates inside the device. Simulation results display that streamlines near the tuning are smoother for the modified structures than those for the original one. In addition, there is no flow separation occurring near the turning. Under the designed and small mass flow conditions, total pressure and static pressure loss coefficients between inlet and outlet for the modified cases are reduced more that 6%. This demonstrates that aerodynamic performances of the modified exhaust steam device are improved.

关 键 词：直接空冷机组 排其装置 导流板 湍流模拟 

分 类 号：TK262[动力工程及工程热物理—动力机械及工程]