Numerical study of the relationship between heat transfer enhancement and absolute vorticity flux along main flow direction in a channel formed by a flat tube bank fin with vortex generators

• Published in: International journal of heat and mass transfer 2009-03, Vol.52 (7), p.1794-1801
• Main Authors: Chang, Li-Min, Wang, Liang-Bi, Song, Ke-Wei, Sun, Dong-Liang, Fan, Ju-Fang
• Format: Article
• Language: English
• Subjects: Absolute vorticity flux; Convective heat transfer; The secondary flow; Vortex generator; Vorticity flux
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2008.09.029

The secondary flow is frequently used to enhance the convective heat transfer. In this paper, the cross-averaged absolute vorticity flux in the main flow direction is used to specify the intensity of the secondary flow produced by vortex generators that are mounted on a three-row flat tube bank fin surfaces. The relationship between the intensity of the secondary flow and the strength of convective heat transfer is studied using a numerical method. The results reveal that cross-averaged absolute vorticity flux in the main flow direction can reflect the intensity of the secondary flow; a significant relationship between this cross-averaged absolute vorticity flux and span-averaged Nusselt number exists for the case studied. This cross-averaged absolute vorticity flux can account only for the secondary flow effects on convective heat transfer but cannot quantify the effects of developing boundary layer on convective heat transfer.