For single phase heat exchange,the irregularsurface of corrugated tubes constantly changes thefluid low direction,increases the turbulence of fluidand thinners the laminar flow layer,and thus enhanc-es heat transfer.For condensation process,as corru-gated tubes constantly change curvature along axis,the condensate can quickly form lets to separatefrom the outer tube surface,thus reduces film heatresistance and enhances heat transfer.
