Abstract
This study deals with flow behavior and associated heat transfer in a pulsating duct flow. Among the several parameters that govern the transport phenomena of pulsating flow, the effects of pulsating frequency and amplitude on flow instabilities in the rectangular duct is mainly discussed in this paper. Mechanisms of the interaction between these two kinds of governing parameter's effects on flow behavior are not cleared yet. Hydrogen bubble method was employed for the qualitative understanding of the flow structure with periodical velocity fluctuation. Results showed that heat transfer enhancement in the central and downstream region was attributed to the restraint of the boundary-layer development induced by the periodical temporal velocity fluctuation not to the large-scale fluid mixing such as turbulence developed from small-scale flow instabilities occurred in the upstream region.
