1、Based on orthogonal experiments, the experiential formulas of fin height and thickness were obtained.
2、However the fin height, fin Angle and distance of finned tube have the large influence to the finned tube heat, all of them exist the optimal geometrical dimensions.
3、It increases heat transfer significantly while the increasing pressure drops by a lesser amount. The better geometrical parameters are fin shape for trapezoid,or peak shape for flat and Valley shape for round,with spiral angle 10～25°,fin height 0.15～0.20 mm,and number of fins 60～70.
