Simulations of a prototypical device using pyroelectric materials for harvesting waste heat

This paper is concerned with directly converting waste heat into electricity using pyroelectric materials. A prototypical pyroelectric converter is simulated by solving the two-dimensional mass, momentum, and energy equations using finite element methods. The pumping power and the electrical power generated are estimated from the computed pressure, temperature, and velocity. The results show that the energy efficiency increases as the density and specific heat of the working fluid and of the pyroelectric material decrease. Moreover, the power density increases as the density and specific heat of the working fluid increase and those of the pyroelectric material decrease. One can reasonably achieve an energy efficiency of 40% of the Carnot efficiency and a power density of 24 W/L of pyroelectric materials. (C) 2008 Elsevier Ltd. All rights reserved.