摘要
为了研究新型换热器——矩形管束换热器的传热性能,采用矩形缩放管间插入一组旋流片来研究旋流片下游的传热与流阻性能,并与光滑矩形管的传热和流阻进行比较。实验结果表明:在实验范围内(19 000<Re<44 000),随着下游距离的增大,旋流片产生的自旋流逐渐衰减,局部Nu数和阻力系数减小,并且局部Nu数的下降速度要慢于阻力系数的;当下游距离在0—200 mm时,阻力系数下降的程度较大;旋流片下游在得到强化传热的同时,阻力增加也很大。
To study the heat transfer performance of a new type heat exchanger-rectangle tube bundle heat exchanger, the characteristics of heat transfer and flow resistance of the converged-diverged rectangle tube supported by twisted-leaves were investigated experimentally and compared with those of rectangle tube of smooth plates. The experiment shows that when Reynolds number is in the range of 19 000-44 000, the free swirl flow gradually decays, the local Nusselt number and friction factor decrease when the distance from tail of twisted-leaves increases, and local Nusseh number decreases more slowly than friction factor. In the range of 0-200 mm far from the twisted-leaves, the friction factor decreases more rapidly than that at other locations. The flow resistance increases greatly when the heat transfer enhancement is obvious in the experimental domain.
出处
《化学工程》
CAS
CSCD
北大核心
2010年第3期14-17,共4页
Chemical Engineering(China)
基金
国家自然科学基金资助项目(20776046)
关键词
矩形管束换热器
矩形缩放管
旋流片
rectangle tube bundle heat exchanger
rectangle converged-diverged tube
twisted-leaf
