Numerical Simulations Versus Experimental Data for a Pyroelectric Energy Converter Harvesting Waste Heat

This paper is concerned with the direct energy conversion of waste heat into electricity using pyroelectric materials. It reports detailed numerical simulations of a prototypical pyroelectric energy converter assembled experimentally and previously reported. The device consisted of a hot and cold source separated by a series of microchannels supporting pyroelectric thin films. A piston was used to vertically oscillate a working fluid back and forth between the thermal sources. The experimental device was fully instrumented with thermocouples and pressure sensor. The transient two-dimensional mass, momentum, and energy equations were solved numerically to determine the local and time-dependent temperature at various locations inside the device for operating frequency varying from 0.025 to 0.061 Hz. Excellent agreement was found between the simulated and experimentally measured local temperatures at all operating frequencies considered. These results confirm our previous numerical results and the simulation tool can now be used to design the next generation of pyroelectric energy converters.