The effects of rotation on the developing turbulent flow and heat transfer in uniformly heated rectangular duct of 2:1 aspect ratio were investigated theoretically and experimentally with the emphasis on the theoretical part.;Numerical computations were performed first for the non-rotating case, for the square and rectangular geometry. Both turbulence models produced results in general agreement with the experimental correlations.;Numerical results obtained for the rotating case indicate that the rotation increases the heat transfer and pressure drop. There is a minimum value of Grashof number, called here, the critical Grashof number G(,c), below which the rotational effects are insignificant. The critical Grashof number increases with Reynolds number and is larger in the entrance region than for the fully developed flow.;The centripetal buoyancy and Coriolis force, arising in this mode of rotation, rearrange markedly the transverse flow pattern and this in turn affects the axial velocity and temperature distributions in the lateral plane. The maxima in these distributions are shifted radially outward in the direction of the centripetal buoyancy force.;Finite-difference solutions for developing turbulent flow and heat transfer in stationary and axially rotating rectangular ducts were obtained. The computations employed the isotropic k-(epsilon) model and algebraic stress model of turbulence and a marching technique to integrate the governing equations.;The numerical solution predict the stable and unstable regions in the flow. In the case of clockwise rotation, the stable region is predicted near the bottom wall and the unstable region near the top wall of the duct. The stable region increases in size with an increase of Grashof number and axial position. The heat and momentum transfer are reduced in the stable region and enhanced in the unstable region with respect to the stationary case. The heat transfer was found to be reduced and enhanced more than the momentum transfer.;The experiments were carried out in a heated rectangular duct of 2:1 aspect ratio, where the duct is parallel but displaced from the rotor axis. Data on heat transfer are obtained for the values of Reynolds number: 10,000 and 20,000.;The heat transfer results from the theoretical predictions have been compared with the experimental data. The present computations are in qualitative agreement with experimental data, except for the value of critical Grashof number. Both turbulence models tested in this work underpredicted the critical Grashof number. (Abstract shortened with permission of author.)
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