Numerical Study of Steady Forced Convection in a Grooved Annulus Using a Design of Experiments

Numerical simulations have been performed to study the flow and heat transfer characteristics in the annular space between an inner smooth-cylinder rotating at constant angular velocity and an outer stationary grooved one. A first series of calculations were conducted to determine the ranges of Taylor number and longitudinal aspect ratio for which a two-dimensional modeling can be considered as valid. To this end, a map showing the domain of validity of two dimensional computations is presented. The assumption of circumferential periodicity of the flow is then justified in the range of Taylor numbers investigated. A number of simulations were carried out to investigate the effects of the geometrical parameters describing the cross section of the grooved annulus for various Taylor numbers. To end, correlations describing the influences on the main parameters both on the friction factor and Nusselt numbers are derived by using a design of experiments.