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 Title: A direct numerical simulation of fully developed turbulent channel flow with passive heat transfer Author(s): Lyons, Stephen Lincoln Doctoral Committee Chair(s): Hanratty, Thomas J. Department / Program: Chemical and Biomolecular Engineering Discipline: Chemical and Biomolecular Engineering Degree Granting Institution: University of Illinois at Urbana-Champaign Degree: Ph.D. Genre: Dissertation Subject(s): Engineering, Chemical Abstract: A direct numerical simulation of a fully developed turbulent channel flow with passive heat transfer is performed. The time-dependent three-dimensional Navier-Stokes equations and advection-diffusion equation are solved numerically using a pseudospectral technique with 1,064,960 grid points in physical space (128 x 65 x 128 in x, y, z). No subgrid scale model is employed since all essential turbulence scales are resolved. The Reynolds number is 2262, based on the half channel height and bulk velocity, and the Prandtl number is 1. The Nusselt number is predicted to be 25.36. A large number of one-point turbulence statistics are computed and compared with existing experimental data taken at similar Reynolds and Nusselt numbers. Agreement with the existing experimental data is excellent except for some discrepancies in the near wall region, y$\sp+$ $<$ 10. A number of two-point statistical correlations with spanwise, streamwise, and/or normal separation are also computed and reported. Mean and turbulent kinetic energy, Reynolds stress, and mean and turbulent temperature variance budgets are presented. Instantaneous and conditionally averaged flow structures are also presented. The momentum and heat transport in the viscous wall region, 0 $<$ y$\sp+$ $<$ 30-40, is found to be controlled by wall eddies with a spanwise scale of 50$\sp+$ tilted 30-50 degrees from the wall and rotating in the y-z plane. These eddies are periodic in the spanwise direction with an average periodicity length of $\sim$100$\sp+$. The wall eddies are elongated in the streamwise direction with streamwise extent $\sim$200-400$\sp+$. Issue Date: 1989 Type: Text Language: English URI: http://hdl.handle.net/2142/22234 Rights Information: Copyright 1989 Lyons, Stephen Lincoln Date Available in IDEALS: 2011-05-07 Identifier in Online Catalog: AAI8924888 OCLC Identifier: (UMI)AAI8924888
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