ABSTRACT
A numerical investigation has been undertaken to study fluid flow and heat transfer
through channels roughened by arrays of either attached or detached ribs. This
technique is spilled extensively in the internal cooling. Indeed, the heat transfer
enhancing ribs are widely used in many industrial applications such as the cooling of
gas turbine blades, and heat exchangers. Calculations are carried on five geometric
configurations. The governing equations are solved in a two-dimensional domain using
a control volume method and the SIMPLE algorithm for the velocity-pressure coupling
is employed. The rib height-to-channel hydraulic diameter, detached distance-to-height
ratio, pitch-to-height ratio, Reynolds and Prandtl numbers are respectively fixed at
h=0.2, C=0 and C=0.5, p=10, Re=500 and Pr=0.71. The grid is non uniform and is
highly concentrated close to the rib to capture high gradient velocity, pressure and
temperature. A uniform temperature through the ribs and all walls was assumed. The
interaction between the hydrodynamics and thermal structures is put in evidence.
Geometrical configurations effect on flow and heat transfer has been detailed by a
systematic analysis. From the local results carrying on the temperatures pattern, the
profiles of the local Nusselt number in channel is presented for different geometrical
configurations.