PREDICTION OF TURBULENT FLUID-FLOW AND HEAT-TRANSFER IN A FLOW ROTATING PERIODICAL 2-PASS SQUARE DUCT

Turbulent fluid flow and heat transfer characteristics are analyzed nu merically for fluids flowing through a rotating periodical two-pass sq uare channel. The smooth walls of this two-pass channel are subject to a constant heat flux. A two-equation k-epsilon turbulence model with modified terms for Coriolis and rotational buoyancy is employed to res olve this elliptic problem. The duct through-flow rate and rotating sp eed are fixed constantly; while the wall heat flux into the fluid is v aried to examine the rotating buoyancy effect on the heat transfer and fluid flow characteristics. It is disclosed that the changes in local heat transfer due to the rotational buoyancy in the radially outward flow are more significant than those in the radially inward flow. Howe ver, the channel averaged heat transfer is altered slightly due to the rotational buoyancy in the both ducts. Whenever the buoyancy effects are sufficiently strong, the flow reversal appears over the leading fa ce of the radially outward-flow channel, and the radial distance for i nitiation of flow separation decreases with increasing the buoyancy pa rameter. A comparison of the present numerical results with the availa ble experimental data by taking buoyancy into consideration is also pr esented.