管间高黏度流体的有效传热温差缓变特性  

Slow change of effective heat transfer temperature difference of highly viscous fluid on shell side

作　　者：洪宇翔[1] 邓先和[1] 张连山[1] 

机构地区：[1]华南理工大学传热强化与过程节能教育部重点实验室,广东广州510640

出　　处：《化工学报》2012年第2期441-447,共7页CIESC Journal

基　　金：国家自然科学基金项目(20776046);2011年度广东省重大科技专项(2011A080804012)~~

摘　　要：通过数值模拟,研究了85%甘油在旋流片支撑光滑管管束间纵向流动的传热与流阻特性,并与无支撑光滑管束的纵向流动进行了对比,揭示了高黏度流体置换类强化传热方法的有效传热温差缓变特性机理。研究结果表明,层流时,小扭率与大角度旋流片支撑的光滑管管束的传热综合性能更佳,旋流片支撑光滑管管束在有旋流片段可以通过提高有效传热系数与增加有效传热温差的双重途径提高传热速率,而在旋流片下游段则可以利用有效传热温差的缓变特性继续维持较大的传热速率,从而能避免过多的流体置换次数,极大幅度地降低了流体的输送功耗。The heat transfer and flow characteristics of 85% glycerin in smooth tube bundle supported by uniformly spaced twisted tapes were studied and compared with the thermal performance of smooth tube bundle without support by numerical simulation.Slowly changing characteristics of effective heat transfer temperature difference with the replacement method for heat transfer of highly viscous fluid was also discussed.The results indicate that the smooth tube bundle supported by twisted tapes has better integrated performance than the smooth tube bundle under laminar flow.Smaller twist ratio and larger angle of twisted tapes are more efficient to improve the heat transfer performance.In the segment with twisted tapes,the heat transfer is improved by enhancement of both heat transfer coefficient and effective temperature difference,and in downstream of twisted tapes the effective temperature difference is changed slowly,still improving the heat transfer.This is a novel way to enhance the heat transfer by avoiding frequent replacement of fluid and saving energy for fluid transportation.

关 键 词：强化传热 旋流片 有效传热温差 

分 类 号：TQ051.5[化学工程]