Numerical Study of Flow and Heat Transfer in a Square Duct with Convex and Concave Semicircular Ribs
In this study, fluid flow with heat transfer in a square channel with mountedribs on the channel wall is numerically investigated. And the effect of the rib shape on increasing the heat transfer in the flow regime is investigated. For this purpose, the convex and concave semicircular profiles have been used to form the ribs. The channel inlet Reynolds number is 20,000.The details of turbulent flow structure temperature fields, local heat transfer, normalized heat transfer, and thermal performance factor were obtained using Computation Fluid Dynamics (CFD) with the K-ɛ and Large Eddy Simulation(LES) turbulence model and constant heat flux thermal boundary conditions applied to all surfaces. Comparisons between the numerical and experimental results of the flow fields for the two shapes along the channel are performed to validate the numerical method. Heat transfer results for tree turbulator geometries are compared. These results can be used to optimize the cooling of gas turbine blades.
Keywords - Heat Transfer, Air Duct, Convex and Concave Rib, LES Turbulence Model.