A Numerical Investigation on Turbulent Convective Flow Characteristics Over Periodic Grooves of Different Curvatures

The effect of curvatures on extended surfaces found many applications in heat transfer devices since a decade. So, understanding the underlying flow physics and heat transfer is the prime importance of the present work. In this work, numerical simulations of turbulent forced convection are conducted by introducing curvatures at sharp corners of the periodic groove at the lower wall. A constant heat flux is supplied in the lower wall while the upper wall is insulated. Computations were carried out using k- ∈ (RNG) model in RANS formulation implemented in ANSYS Fluent 19.2®. The simulations are performed over varying Reynolds numbers ( \(Re\) ) of 6000–36,000 where ratio of groove width to channel height, groove pitch ratio, and depth ratio are kept constant as 1, 2, and 0.5, respectively. Assessment of coefficient of heat transfer, frictional losses, and magnitude of heat enhancement are systematically carried out over varying radii of curvatures on grooves. The insertion of curvatures improves 10–12% in overall heat transfer, while overall 5% heat transfer enhancement is observed with increment in curvature radius, Reynolds number, and friction factor. The present study proposes several optimal parameters for the enhancement of heat transfer in practical thermal devices.