Time and phase average heat transfer in single and twin circular synthetic impinging air jets

Heat transfer and flow characteristics of a pair of adjacent impinging synthetic jets

“…However, the jet profile is not as wide and developed as that of H = 24D. These observations are similar to the recent observations by Greco et al (2014) for local heat transfer measurements of twin circular impinging synthetic jets. Their results demonstrated a single impingement profile as the H/D value was increased, whereas for lower H/D values, two distinct impingement zones were observed.…”

“…This yields values of Nu 0 = 9.4, 8.4 and 7.6 for H/D = 6, 12 and 24 respectively. Heat transfer measurements of a circular jet pair at H/D = 6, S/D = 3 and U = 180°byGreco et al (2014) showed an increase in Nu max of about 18% compared to a single circular jet. For the slot jets in this study, an increase in Nu max of 36% compared to a single jet is observed for the same val-ues of H/D, S/D and U.…”

Modelling of efficiency of synthetic jet actuators

“…Continuous and pulsed jets are nowadays quite largely used as devices for flow control (e.g., Glezer and Amitay [1], Cattafesta and Sheplak [2]) and heat transfer applications (e.g., Chaudhari et al [3], Valiorgue et al [4], Greco et al [5]). The continuous request for a size reduction of such systems has led researchers to focus their efforts on the design of new technology devices.…”

An experimental investigation on comparison of synthetic and continuous jets impingement heat transfer

“…Since the foil sheet is thin enough that the Biot number (Bi ¼ hd=k where k is the thermal conductivity and d is the thickness of the foil) is much less than unity, the temperature is reasonable to be considered practically as uniform across the foil thickness [31]. The local convective heat transfer coefficient on the target surface was evaluated as …”