| Abstract: | The relations between the point for transition from the transition zone to complete turbulence and the fin height, fin width as well as fin density in 3D internally finned tubes have been investigated experimentally. At the same time, the performance of heat transfer and pressure drop in the tubes have been investigated when the flow is completely turbulent. Three expressions hale been obtained for (1) the Reynolds criterion for transition from the transition zone to complete turbulence, (2) the Nusselt number of complete turbulence in the tubes, and (3) the Fanning friction factor of complete turbulence in the tubes. These expressions can be used in engineering designs. © 1999 Scripta Technica, Heat Trans Asian Res, 28(3): 183–188, 1999 |
