Heat transfer enhancement by induced vortices in the vicinity of a rotationally oscillating heated plate

Abstract

The present study is conducted to investigate the flow field and its impact on the thermal characteristics in the immediate surroundings of a rectangular flat plate, subjected to rotational oscillations in a quiescent fluid. The plate is heated with a constant heat flux on both faces during its rotational motion about one of its edges. The induced flow and thermal characteristics were simulated experimentally and computationally using the dynamic mesh method. The flow around a fabricated laboratory model was visualized with smoke particles and the surface temperature was recorded using J-types thermocouples. During the plate’s flapping cycles, computational and experimental results exhibit the presence of strong vortices near the free edges. When shed off, these vortices participate significantly in the enhancement of the cooling rate of the heated surface. The time dependent surface temperature distribution is symmetrical and characterized by a transient unsteady periodic variation which precedes a steady periodic phase. The results of current investigations present an interest in the cooling of portable electronic devices and shed light in the elephant’s metabolic heat regulation by the flapping of its pinnae.