Multicellular piezoelectric actuator for setting in motion fluids, and heat exchange enhancement

In this paper, a multi-cellular piezoelectric actuator has been dimensioned, designed and integrated into an electro-active morphing wall heat exchange demonstrator. The design study was performed using finite element simulations. Numerical study shows that the obtained deflections vary from 77 to 462 μ m for applied displacement ranging from 3 to 18 μ m. Once the operating principle validated, a series of actuators has been machined and tested. Dynamic tests (unloaded) gives a maximum displacement about 230 μ m for a frequency ranging up to 100 Hz. However the static tests give results with a good agreement with simulation. The developed actuators have been introduced into a demonstrator to show the feasibility of an intensification of heat exchange by electro-active morphing. The recovered data have demonstrated the feasibility of pumping for a traveling wave of 5 Hz closing quasi-totally the channel. Another result is the reduction of wall temperatures during the application of a traveling wave on the, thereby that the heat transfer was intensified. Moreover, an increase in the rate of flow was observed. All this results demonstrate the enhancement of heat transfer.