This study investigates the feasibility of integrating thermoelectric devices into a large-capacity liquid heat exchanger (up to 100 kW) [1]. Typically, thermal-electrical conversion is inefficient and thermoelectrics are only used in low-power applications (<1 kW). The incentive for using thermoelectrics, however, lies in their compact size, light-weight, high reliability, and sub-ambient cooling [2,3]. In this study, a subscale thermoelectric heat exchanger is designed (see Fig. 1), fabricated and optimized for performance through testing and simulation. Specifically, direct fluid contact and jet-impingement were used to improve heat transfer at both hot and cold junctions of the thermoelectric. A schematic of the design concept can be seen in Fig. 2. This approach resulted in a five-fold increase in the cooling coefficient-of-performance. Experimentally validated predictions also demonstrated that a 100-kW heat exchanger is lighter per unit-power than comparable vapor-compression systems. This feasibility study raises the outlook of reducing thermoelectric technology to practice in large heat load applications.

This work was presented in the May 2012 Itherm Conference [1].

[1] Lu, K., et al. (2012). “High-capacity Thermoelectric Heat Exchanger.” In press, ITherm 2012 Conference Proceedings, San Diego USA, May 31, 2012.

[2] Buist, M. J. (1996). Transient analysis of thermal junction within a thermoelectric cooling assembly. 15th International Coference on Thermoelectrics. Pasadena, California.

[3] Buist, R. J. (1994). Thermoelectric measurement and design technology. Chemivtsy, Ukraine.