IJMTES – STUDY ON HEAT TRANSFER SYNTHETIC AIR JET FOR EFFECTIVE COOLING

Journal Title : International Journal of Modern Trends in Engineering and Science

Author’s Name : Poovendran C unnamed

Volume 03 Issue 01 2016

ISSN no:  2348-3121

Page no: 23-25

Abstract – Synthetic jet is a relatively new technique which synthesizes stagnant air to form a jet resulted from periodic oscillations of a diaphragm in a cavity. Synthetic jet actuator is composed of a closed cavity with one end covered by electromagnetic actuator and a circular orifice at other end. Usually the jet is formed due to the entrainment of the vortex pairs which are rotating in opposite direction and formed at the edges of the orifice. They have promising application in various fields such as jet vectoring, electronics cooling, and boundary layer separation. In present work the synthetic jet is driven by acoustic speaker for the impingement of jet on the heated surface. The temperature distribution across the heated surface is measured with the help of infrared thermal camera. The local heat transfer study of synthetic jet for effective cooling on flat surface in terms of Nusselt number and Heat transfer coefficient by varying parameters such as excitation frequency (60 Hz to 180 Hz), axial distance between target plate and orifice plate (Z/d= 1 to 12) with maintaining constant ratio of cavity length to cavity diameter is equal to unity, i.e. L/D=1throughout work. The results show that at 160Hz frequency for the axial distance and diameter ratio in between of 5-6, the cooling is very effective. The Nusselt number is peak at stagnation point for all frequencies and attenuates monotonically in the radial direction. The results are expected to be helpful for the development and designing of the synthetic jet.

Keywords: Stagnant air; Jet; thermal

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