Turbulent heat transfer and fluid flow characteristics for air flow in an unsymmetrically heated triangular duct
Abstract
Experiments were performed to obtain the heat transfer and friction factor characteristics for an asymmetrically heated triangular duct. Two of the walls were heated so as to obtain axially uniform heat flux and circumferentially uniform temperature. The third wall was made of an insulator plastic material and was not directly heated. Another triangular duct, with identical inner geometry, was positioned upstream of the heated duct and served as the hydrodynamic development duct. The experimentally determined thermally developed values of the Nusselt number were compared to correlations found in the literature for turbulent heat transfer in uniformly heated circular tubes. The predicted values were at least 15 per cent higher than the measured ones. A modification of the Petukhov-Popov equation, using the actual measured values of the friction factor for the heating runs, predicts values of the Nusselt number within 5 per cent of the measured values. The measured values of the Stanton numbers were within 4 per cent of those from a numerical finite-difference solution from the literature.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- March 1980
- Bibcode:
- 1980PhDT........42A
- Keywords:
-
- Air Flow;
- Fluid Flow;
- Friction Factor;
- Turbulent Heat Transfer;
- Finite Difference Theory;
- Nusselt Number;
- Stanton Number;
- Fluid Mechanics and Heat Transfer