Unileg Thermoelectric Generator Design for Oxide Thermoelectrics and Generalization of the Unileg Design Using an Idealized Metal
- 315 Downloads
The unileg thermoelectric generator (U-TEG) is an increasingly popular concept in the design of thermoelectric generators (TEGs). In this study, an oxide U-TEG design for high-temperature applications is introduced. For the unicouple TEG design, Ca3Co4O9 and Al-doped ZnO are used as the p- and n-leg thermoelectric materials, respectively. For the U-TEG design, constantan and Ca3Co4O9 are employed as conductor and semiconductor, respectively. The reduced current approach (RCA) technique is used to design the unicouple TEG and U-TEG in order to obtain the optimal area ratio. When both the unicouple TEG and U-TEG were subjected to a heat flux of 20 W/cm2, the volumetric power density was 0.18 W/cm3 and 0.44 W/cm3, respectively. Thermal shorting between the hot and cold sides of the generator through the highly thermally conducting conductor, which is one of the major drawbacks of the U-TEG, is overcome by using the optimal area ratio for conductor and semiconductor given by the RCA. The results are further confirmed by finite-element analysis using COMSOL Multiphysics software. Furthermore, the U-TEG design is generalized by using an idealized metal with zero Seebeck coefficient. Even though the idealized metal has no impact on the power output of the U-TEG and all the power in the system is generated by the semiconductor, the U-TEG design succeeded in producing a higher volumetric power density than the unicouple TEG design.
KeywordsUnileg thermoelectric generator TEG thermoelectric volumetric power density thermal shorting
Unable to display preview. Download preview PDF.
- 6.G.J. Snyder, in Thermoelectr. Handb. Macro to Nano (Taylor & Francis, Boca Raton, 2006), Chapter 11, pp. 1–26.Google Scholar
- 11.F.J. DiSalvo, Science (80) 285, 703 (1999).Google Scholar
- 13.D.R. Smith and F.R. Fickett, J. Res. Natl. Inst. Stand. Technol. 100, 119 (1995).Google Scholar
- 14.Y.A. Cengel, R.H. Turner, and J.M. Cimbala, in Fundam. Therm. - Fluid Sci., 3rd ed. (McGraw Hill Higher Education, Singapore, 2008), pp. 653–722.Google Scholar