The effect of off-center placement of twisted tape on flow and heat transfer characteristics in a circular tube

Abstract This study is conducted to investigate the effect of off-center placement twisted tape on flow distribution and heat transfer in a circular tube. The width 20, 18, 16, 14 12 mm performance discussed under same twist ratio 2.0. numerical analysis field, average Nusselt number, friction factor thermo-hydraulic parameter tube are with Reynolds number ranged from 2600 8760. results indicate that fitted center-placed tapes at various 7–51% higher than plain tube, low region was found more effective high region. for attached wall shows better tape. With smaller width, increasing Nu-wall/Nu-center obtained. 3 18%. However, use inserts not beneficial energy saving. parameters convective helium gas flowing below unity calculated