AN EXPERIMENTAL INVESTIGATION OF CONVECTIVE HEAT-TRANSFER FROM THE HEATED FLOOR OF A RECTANGULAR DUCT TO A LOW-FREQUENCY, LARGE TIDAL DISPLACEMENT OSCILLATORY FLOW

This research experimentally investigates convective heat transfer fro m a heated floor section of a rectangular duct to a low frequency, lar ge tidal displacement, oscillatory flow. Phase correlated oscillatory flow velocity and temperature profiles are presented. Favorable pressu re gradients, with respect to time, are shown to stabilize the flow wh ile adverse pressure gradients are shown to sustain velocity fluctuati ons. Higher heat transfer rates are obtained for smaller duct heights, higher oscillation frequencies, and larger tidal displacements. A non dimensional correlation based on a new correlation parameter has been obtained for the oscillatory-flow Nusselt number.