International Journal of Heat and Mass Transfer, Vol.131, 1205-1210, 2019
Development of novel plate heat exchanger using natural graphite sheet
Natural flake graphite sheets have superior physical properties such as: high in-plate thermal conductivity (300-600 W.m(-1).K-1), light weight (2.1 g.cm(-3)), negligible coefficient of thermal expansion and resistivity to corrosion under high temperatures. With the new roll-embossing process, fabrication of graphite sheets with different patterns has become fast and economical. These properties make natural graphite an excellent candidate for thermal applications, such as heat exchangers (HEXs), as an alternative to metallic alloys. This study presents a new fabrication method for chevron-type plate HEXs, as a proof-of-concept demonstration, using flat embossing process. To measure the performance of the proposed graphite plate heat exchanger, a custom-designed water-water experimental testbed is designed based on ANSI/AHRI Standard 400. The heat transfer rate and the pressure drop of the fabricated graphite plate heat exchanger are compared to a conventional stainless-steel chevron HEX with similar plate dimensions and number of plates. Compared with the commercially available unit, the proposed graphite plate heat exchanger shows identical thermal performance and a 26% higher pressure drop, due to its narrower channel design. This provide a promising platform for future optimized designs of efficient, corrosion resistance, and cost-effective graphite-based heat exchangers for a number of industrial applications. Crown Copyright (C) 2018 Published by Elsevier Ltd. All rights reserved.
Keywords:Heat exchanger design;Natural graphite;Roll-embossing;Heat transfer modelling;Experimental study