内置扭带波纹管内熔盐传热特性数值研究  

Investigation on heat transfer of molten salt in bellows with twist tape inserts

作　　者：王为术[1] 扶麟 李振 许鹏[1] 

机构地区：[1]华北水利水电大学热能工程研究中心,郑州450045

出　　处：《低温与超导》2017年第10期58-64,共7页Cryogenics and Superconductivity

基　　金：河南省科技创新人才杰出青年计划(No.154100510011);河南省高校科技创新团队支持计划(No.16IRTSTHN017)资助

摘　　要：本文针对熔融盐吸热器传热与流动特性进行了深入的理论研讨与分析,对于太阳能热发电系统中吸热器传热过程中高辐射热流密度的特点,设计并建立内置扭带波纹管物理模型,采用RNG k-ε模型,对内置扭带的波纹管内熔盐传热特性进行数值模拟。分析了集热管轴向速度分布和横向截面二次流速和温度分布,对比了不同管型的集热管内换热效果和阻力系数f。研究结果表明:在入口雷诺数Re为12000~35000的范围内,相比圆管和普通波纹管,Nu均有提高,且随Re的增加呈递增趋势;普通波纹管和内置扭带的波纹管的阻力系数f都随着Re的增加呈递减趋势,相比于圆管,波纹管和内置扭带波纹管的f分别提高了282.3%~354.9%和1154.4%~1339.0%。In this study, a computational model of bellows with twisted tape inserts within a Reynolds number range of 12000 -35000 was constructed , the molten fluoride salts heat transfer characteristic was numerically simulated using the RNG k - e two - equation turbulence model. The flow axial - velocity , cross section secondary flow velocity and temperature distribu- tion were analyzed, the tube heat transfer effect and drag coefficient were compared with different tube forms. The results indicate that compared to normal bellows and smooth tube , Nusseh number of bellows with twisted tape inserts increases, and on the rise with the increase of Reynolds number. The drag coefficient of normal bellows and bellows with twisted tape inserts declines with the increase of Reynolds number. Compared to smooth tube, the drag coefficients of bellows and bellows with twisted tape inserts increases of 282.3% - 354.9% and 1154.4% - 1339.0%.

关 键 词：波纹管 扭带 熔盐 强化传热 流动特性 数值模拟 

分 类 号：TK124[动力工程及工程热物理—工程热物理]