不连续双斜向内肋强化换热管性能

引言管壳式换热器在石油化工、能源动力、造纸、制药等领域应用十分广泛,换热强化对于其节能降耗具有十分重要的意义.近30年研制开发出几十种强化换热管,例如螺旋槽管、波纹管和翅片管等,并得到了比较成功的应用.但相关的研究多数仍然停留在经验的基础上,即研究者根据其经验设计出某种具体的强化技术,然后通过实验和数值计算归纳出适用于一定范围的经验关联式.因此,传热强化研究目前仍属于技术领域[1],研究人员通常所采用的经验性的研究方法不可避免存在着一定的局限性.过增元等[2]提出了一种新的强化换热理论———对流换热场协同理论,为对…

Performance of enhanced heat transfer tube with discrete double-inclined ribs

The numerical and experimental study was carried out for the discrete double-inclined ribs (DDIR) tube developed on the basis of the convective heat transfer field-coordination theory. The experimentally fitted relationships of heat transfer and resistance coefficients were given. The periodical change of the original surface specially designed in the DDIR tube induced multi-longitudinal vortex flow and enhanced heat transfer remarkably with less extra flow resistance.When Re=500—2300,heat transfer enhancement of the DDIR tube would be increased by 2.5—6.5 times with a resistance increase of 120%—300% compared to the laminar heat transfer of a circular tube (L/D=300) considering inlet effect. When Re=2300—10⁴,heat transfer enhancement would be increased by 130%—240% with a resistance increase of 130%—220%.When Re=10⁴—5×10⁴,heat transfer enhancement would be increased by 110%—130% with a resistance increase of 220%—240% compared to the circular tube.There was no flow dead zone in the DDIR tube so fouling could be prevented in the tube.Its manufacture could be more efficient and low-cost, therefore it is a kind of heat transfer enhancement tube with excellent overall performance.