ABSTRACT
Synthetic jets are meso-or microscale fluidic devices, which operate on the “zero-netmass-flux” principle. However, they impart a positive net momentum flux to the external environment and are able to produce the cooling effect of a fan sans its ducting, reliability issues, and oversized dimensions. The rate of heat removal from the thermal source is expected to depend on the location, orientation, strength, and shape of the jet. In this chapter, we would like to provide an overview of the synthetic technology, ranging from its basic operating principle and mechanisms of heat transfer enhancement to discussing some possible applications.∗
Synthetic jets have been routinely investigated from the standpoint of flow control (Smith et al. 1998; Crook et al. 1999; Mittal et al. 2001; Mittal and Rampunggoon 2002), thrust vectoring of jets (Smith and Glezer 2002), triggering turbulence in boundary layers (Rathnasingham and Breur 1997; Lee and Glodstein 2001), and heat transfer applications (Mahalingam et al. 2004;Holman et al. 2005;Mahalingam andGlezer 2005). In case of heat transfer applications, the cooling process can be facilitated either by direct impingement of vortex dipoles on heated surfaces (Erbas et al. 2005; Li 2005) or by employing the jets to enhance the performance of existing cooling circuits (Timchenko et al. 2004). In view of these applications, the jet performance can be assessed with various methodologies.
