Fig. 1From: Numerical investigation on turbulent forced convection and heat transfer characteristic in spirally semicircle-grooved tubeGeometries of the roughness tube from the published papers. a Spirally grooved tube (Lu et al. 2013a); b transversely grooved tube (Lu et al. 2013b); c roughness tube (Webb 2009); and d Micro-groove fin-inside tubes (Tang et al. 2007)Back to article page