ABSTRACT
Many applications require turbulent flow to elevate heat transfer to/from a surface to a fluid or between multiple fluids. The use of artificial roughness elements for heat transfer enhancement is discussed in this chapter. Friction and heat transfer similarity laws are presented for tube flows with sand grain roughness or repeated-rib roughness over a wide range of similar and nonsimilar geometric parameters. Turbulent flow heat transfer and friction in tubes, in an annulus, between parallel plates, or in rectangular channels with artificially repeated-rib roughness are thoroughly covered. High-performance turbulence promoters are discussed. This chapter also considers heat transfer enhancement within rotating channels. The effects of Coriolis and rotation buoyancy forces on heat transfer enhancement in rectangular channels with turbulence promoters are presented to aid in the design and analysis of cooled turbine airfoils.
