The integral spiral finned tube has significant advantages compared with the conventional finned tube, which makes it have broad application prospects in boiler economizers. In this study, numerical simulation methods were applied to investigate the effects of base tube diameter, fin height, fin pitch, fin tip width, fin root width, transverse tube pitch and longitudinal tube pitch on the heat transfer and flow characteristics of the integral spiral fin tube. The optimal structural parameters were analyzed through multi-objective optimization. The total heat transfer coefficient is not greatly affected by the fin pitch. With the increase of the longitudinal pitch, the total heat transfer coefficient first increases and then decreases, and the optimum is around 90mm. The optimal structural parameters were obtained while considering the flow and heat transfer characteristics that: the base tube diameter is 32 mm, the fin height is 13 mm, the fin pitch is 7 mm, the fin tip width is 2.4 mm, the fin root width is 4.2 mm, the transverse pitch is 80 mm, the longitudinal pitch is 90 mm, and the inlet flow velocity is 12 m/s.
Keywords Integral spiral finned tub, flow characteristics, heat transfer characteristics, structural optimization, multi-objective genetic algorithm