Fluid Flow and Heat Transfer in Corrugated Wall Channels : 2nd Report, Experiments in the Case Where Channels Are Bent Perpendicularly Two Times

Abstract

In the present experiment augmentation of forced convection heat transfer in single-phase flows was investigated using a channel whose parallel walls are bent perpendicularly at two locations. Heat transfer characteristics in both laminar and turbulent flow situations were observed by varying the pitch. Visualization of the flows revealed the formation of separation bubbles in the corners of the bends and the reattachment of the flows in downstream regions. It is accordingly concluded that augmentation of heat transfer occurs as a result of the reattachment and acceleration of the flows.