Heat transfer in turbulent flow past a surface-mounted two-dimensional rib
- Louisiana State Univ., Baton Rouge, LA (United States). Mechanical Engineering Dept.
Heat transfer measurements and predictions are reported for a separated, turbulent duct flow past a wall-mounted, two-dimensional rib. The computational results include predictions using a standard {kappa}-{epsilon} model, a functionalized {kappa}-{epsilon} model and a nonlinear {kappa}-{epsilon} model. Three different prescriptions for the wall-functions, WF I, WF II and WF III, given respectively by Launder and Spalding (1974) Chieng and Launder (1980) and Johnson and Launder (1982) are examined. The experiments included laser-Doppler flow measurements, temperature measurements, and local Nusselt number results. For WF I, both the nonlinear and standard models predicted the experiments well in the core flow regions and close to reattachment, but both performed poorly in the separated and shear layer regions close to the rib. The nonlinear model yielded more realistic predictions of the streamwise turbulent intensity and the mean streamwise velocities near the high-speed edge of the separated layer and downstream of reattachment. More realistic predictions of the production and dissipation of the turbulent kinetic energy near reattachment were also obtained using the nonlinear and the functionalized model. With WF I and WF II, the models underpredicted the local Nusselt numbers and overpredicted the flow temperatures. With WF III, the predicted results agree with the experimental Nusselt numbers well up to reattachment, after which, it substantially overpredicted the Nusselt numbers. The functionalized model using only the high-Re formulation and curvature corrections in Cartesian coordinates improve the temperature predictions substantially, with the predicted temperatures in the flow in close agreement with those measured.
- Sponsoring Organization:
- National Science Foundation, Washington, DC (United States)
- OSTI ID:
- 455400
- Report Number(s):
- CONF-951135--; ISBN 0-7918-1752-0
- Country of Publication:
- United States
- Language:
- English
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