绕流肋片通道内的流动与换热特性数值研究  

Numerical Investigation on the Flow and Heat Transfer Characteristics of the Flow-Around Rib Channel

作　　者：梁钊 王新军[1] LIANG Zhao;WANG Xinjun(School of Energy and Power Engineering,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《西安交通大学学报》2021年第11期8-16,共9页Journal of Xi'an Jiaotong University

摘　　要：为进一步提高燃气轮机叶片内部冷却中冷却通道内的换热性能,降低通道内的流动损失,采用CFX软件数值研究了在Re为20 000~80 000的范围内,肋间距与肋高比p/e=10的6种肋片在宽高比为4∶1的矩形通道内的换热与阻力特性。研究结果表明:再循环区对肋片下游的换热性能有很大影响,大范围削弱再循环区域会降低通道换热性能和热力性能;绕流肋片通道可以消除实心肋片通道肋片前后缘底部附近的传热恶化区域,而正方形绕流肋通道比圆形绕流肋通道具有更好的综合热力性能;对于绕流肋片通道来说,随着肋片横截面积减少比例的减小,通道综合热力性能增加,但摩擦阻力增大;边长越大的正方形绕流肋片通道的换热性能和综合热力性能越好,边长为实心肋片边长0.8倍的正方形绕流肋片通道获得了所研究肋片中的最佳综合热力性能和换热性能,相对于实心肋结构,正方形绕流肋结构的通道面积平均Nu提高了0.92%~2.73%,加热段摩擦系数减小了10.89%~11.01%,热力性能因子提高了4.92%~6.75%。To further improve the heat transfer performance and reduce the pressure loss in the internal cooling of gas turbine blade, the flow and heat transfer characteristics of six rib structures in the rectangular channel were numerically studied by CFX software under the Reynolds number of 20 000-80 000. The aspect ratio of the rectangular channel was 4∶1, and the rib spacing to rib height ratio(p/e) was 10. The results show that the recirculation zone has a great influence on the heat transfer performance downstream of the rib, and weakening the recirculation zone will reduce the heat transfer performance. The flow-around rib can eliminate the heat transfer deterioration area near the bottom of the leading/trailing edge of the solid rib channel, and the square flow-around rib channel has better thermal performance than the circular flow-around rib channel. For the flow-around rib channels, with the decrease of the rib cross-sectional area reduction ratio ψ, the thermal performance of the channel improves, but the friction factor is increased. The square flow-around ribs with large side-lengths obtain the best thermal performance and heat transfer performance among the ribs studied in this paper. Compared with the solid ribs, the area average Nusselt number of the square flow-around ribs with large side-lengths increases by 0.92%-2.73%, and the friction factor in the heating section decreases by 10.89%-11.01%, which makes the thermal performance factor increase by 4.92%-6.75%.

关 键 词：绕流肋片 带肋通道 强化换热 热力性能 数值计算 

分 类 号：TK47[动力工程及工程热物理—动力机械及工程]