Piezoelectric fans are gaining in popularity as low-power-consumption and low-noise devices for the removal of heat in conﬁned spaces. The performance of piezoelectric fans has been studied by several authors, although primarily at the fundamental resonance mode. In this article the performance of piezoelectric fans operating at the higher resonance modes is studied in detail. Experiments are performed on a number of commercially available piezoelectric fans of varying length. Both ﬁnite element modeling and experimental impedance measure- ments are used to demonstrate that the electromechanical energy conversion (electromechanical coupling factors) in certain modes can be greater than in the ﬁrst bending mode; however, losses in the piezoceramic are also shown to be higher at those modes. The overall power consumption of the fans is also found to increase with increasing mode number. Detailed ﬂow visualizations are also performed to understand both the transient and steady-state ﬂuid motion around these fans. The results indicate that certain advantages of piezoelectric fan operation at higher resonance modes are offset by increased power consumption and decreased ﬂuid ﬂow.
Acoustic devices, air cooling, electromechanical effects, fans, losses, piezoelectric devices
Date of this Version
S. M. Wait, S. Basak, S. V. Garimella and A. Raman, “Piezoelectric Fans using Higher Flexural Modes for Electronics Cooling Applications,” IEEE Transactions on Components and Packaging Technologies Vol. 30(1), pp. 119-128, 2007.