Abstract
Flow visualization and heat transfer experiment were carried out for the three different variations of ribs mounted on the channel duct. In all cases, strong three-dimensional flow thermal structures due to the effect of the side walls and rib gaps were observed. Especially for the ribs with gaps, flow field was characterized by high seed gap flow and tornado like vertical vortices downstream the rib. Such flow structures were found to be effective to recover heat transfer deterioration occurring just behind the full-span rib presently used in the blade cooling system. It was also found that a rib having a gap in the middle of the duct effectively increases heat transfer on the side wall surface.
