顺排管束流动和传热数值模拟  

Numerical Simulation of Flow and Heat Transfer of In-Line Tube Banks

作　　者：刘万旺 许志美[1] 宗原[1] 赵玲[1] 柏德鸿 严水霖 LIU Wanwang;XU Zhimei;ZONG Yuan;ZHAO Ling;BAI Dehong;YAN Shuilin(State Key Laboratory of Chemical Engineering,East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学化学工程联合国家重点实验室,上海200237

出　　处：《华东理工大学学报（自然科学版）》2019年第1期15-22,共8页Journal of East China University of Science and Technology

摘　　要：采用数值模拟的方法考察了列管式换热器中顺排管束的流动和传热问题,计算了不同纵向节径比(S_L/D)和横向节径比(S_T/D)对顺排管束传递特征的影响,并综合评价了其换热效果。结果表明,管排结构中大部分圆管均受尾流影响,在前列圆管尾流的作用下,尾涡结构被改变。相比于单圆管,管排结构强化传热的作用较明显,且对管排横向间距变化较为敏感。结果显示,增大S_L/D和S_T/D均能提高努塞尔数(Nu),但同时阻力系数也随之增大。当S_L/D=2.7,S_T/D=2.5时,管束的综合传热能力最优。此外观察到管排结构可以减小涡脱落频率,对涡脱落起一定的抑制作用,并通过线性拟合得到了管排斯特劳哈尔(St)数与雷诺(Re)数的关系。The flow and heat transfer of the flow through in-line tube banks in a tubular heat exchanger have been numerically studied in this paper.The effects of longitudinal and transverse tube pitch ratio of in-line tube bank on the transfer characteristics of the flow pattern have been investigated quantitatively,and comprehensive heat transfer effect has been evaluated.The simulation results indicate that most of the tubes in the tube banks are affected by wake flow from the tubes in the previous column,and the structure of wake vortex is changed as a result.Compared with single tube,it is found that the capability of heat transfer is greatly improved in tube bank,and the intensification of heat transfer is more sensitive to the variation of the transversing tube pitch ratio.The results also show that both increasing the longitudinal and transversing tube pitch ratio can increase Nu.However,the resistance coefficient is inevitably increased.The tube banks with arrangements as SL/D=2.7 and ST/D=2.5,show the strongest overall heat transfer capability among the investigated arrangements in the present work.In addition,the relationship between St and Re is established for the investigated tube bank.The tube banks can reduce the frequency of vortex shedding compared with single tube,which indicates the vibration from the vortex shedding can be inhibited.The obtained results can provide theoretical guidance for the design of the industrial tubular heat exchanger,correct arrangement of the heated surface and the selection of the heat exchange area.

关 键 词：管排 强化传热 数值模拟 涡脱落 

分 类 号：TK124[动力工程及工程热物理—工程热物理]