| Sustainable development and Low Carbon Economy are very important to improve thedevelopment of our society and devote human to save energy or exploit new energy. It wasascribed to the fact that enhancing the utilized efficiency of the present energy means energysaving. Passive heat transfer augmentation is popularly applied to the fields of heat transferaugmentation, owing to the advantages of its simple structure and no required additionalpower.Longitudinal vortex generator is an effective passive augmentation heat transfer technology.The fluid flow and heat transfer characteristics of a rectangular channel mounted withcombined rectangular wings were experimentally studied in present work. It was found thatthe new combined rectangular wing has effective fluid and heat transfer characteristicscompared to rectangular wing. In addition, it is more effective when the accessory wing isplaced on the leeward of main wing. The accessory wing with 30°attack angle of combinedrectangular wing shows good heat transfer characteristics compared to that of 45°attackangle.The flow structure generated by the combined wings in different cross sections is analyzed.The results show that the corner vortices are formed behind the wings, and the sizes and thecores of the vortices are very different in different positions. The temperature distributions ofthe heat plate in a rectangular channel with longitudinal vortex generator and withoutlongitudinal vortex generator are very different, which reveals that the vortices are veryimportant to improve the heat transfer.In a word, the new combined wing presented in the present work has effective fluid flowand heat transfer characteristics. The PIV system can be used to measure the flow structure and reveal the mechanism of convective heat transfer of longitudinal vortex generators. |
