Proceedings of the Second International Energy 2030 Conference,
November 4-5, 2008, Abu Dhabi, UAE

Application of Thermally-Enhanced Thermoplastics to Seawater-Cooled Heat Exchangers

A. Bar-Cohen
University of Maryland, USA

P. Rodgers
The Petroleum Institute, UAE

J.G. Cevallos
University of Maryland, USA

P. Luckow
University of Maryland, USA

Abstract
In this study, the potential benefits of using thermally-enhanced polymers in high-performance seawater heat exchangers are assessed. The thermal and mechanical properties of commercially available, thermally-conductive resins are reviewed and compared with those of polymer heat exchangers described in the literature, as well as those of metals commonly used in compact heat exchangers, including in seawater-based cooling systems (i.e., Cu-Ni alloys, stainless steel, and titanium). This survey reveals that engineered thermoplastics have sufficiently high thermal conductivities to compete with their metal counterparts.

The thermo-fluid performance of a conceptual, doubly-finned plate liquid-liquid heat exchanger module, is analytically evaluated using the ε-NTU method. The heat transfer rate and coefficient of performance (COP) of this heat exchanger are parametrically assessed for various fin spacings, wall thicknesses, and a near 3 orders-of magnitude range of wall thermal conductivities. This analysis shows that the thermal conductivities achievable with enhanced thermoplastics, 20 W/mK, can provide approximately half the heat transfer rate of an aluminum heat exchanger operating under the same conditions, and 80% of the heat transfer rate provided by a corrosion-resistant, metallic heat exchanger. This study indicates that thermally conductive thermoplastics offer a promising alternative to the use of conventional and/or corrosion-resistant metals in compact, high performance heat exchangers in seawatercooled applications.