ANALYSIS OF HEAT TRANSFER CHARACTERISTICS IN INTERNALLY FINNED TUBES

Abstract

An in-depth physical analysis of turbulent flow and heat transfer mechanisms in internally finned tubes is presented. For a trapezoidal fin shape, the numerical analysis produced a series of full flow visualizations to clarify the governing mechanisms in fin tube flow. The parametric study explored the effects of number of fins N, nondimensional fin height H, helix angle γ, and fin width s on both friction and heat transfer. Three representative fin tube geometries in the range of , and , were studied. In the literature, the governing physics of tall fin and microfin tubes are believed to be different. However, the current visualization results suggest that there is a continuum in the governing flow physics regardless of fin geometry.

Notes

The authors would like to express their appreciation to the National Computational Science Alliance (NCSA) for providing supercomputer resources and to the Natural Science Foundation (NSF) for Grant: CTS-9412596, which has supported much of this research. The second author's work was supported under NSF Grant CISE-9985340. We would like to thank Dr. David L. Marcum and Mr. John A. Gaither at Mississippi State University for providing their mesh generator, and Dr. Farzin Shakib of ACUSIM for providing his finite-element solver and releasing the routines required for the addition of out turbulence modeling routines.