Heat transfer analysis of carbon fiber-reinforced corrugated polymer plate heat exchangers

Abstract

Despite their low thermal conductivity, polymer heat exchangers are widely utilized owing to their low weight, manufacturing flexibility, strength, and corrosion resistance. A carbon-fiber-reinforced polymer (CFRP) with enhanced thermal conductivity was used to fabricate a corrugated plate heat exchanger to obtain a lightweight, flexible, high-strength, and corrosion-resistant structure. Then a heat exchanger application experiment was conducted and its applicability to the plate heat exchanger evaluated. The electrophoretic deposition process and vacuum-assisted resin infusion molding were used to fabricate the heat exchangers, and hexagonal boron nitride/copper (hBN/Cu) composites were used to improve the thermal conductivity of the CFRP plates. Experimental tests were conducted to investigate the heat transfer performance of various plate materials, and computational fluid dynamics (CFD) modeling was used to analyze underlying causes. The heat transfer performance of the hBN/Cu-coated CFRP plate was approximately 10 % higher than that of the CFRP plate. This is attributed to the surface, fluid, and thermal properties of the material. The thermal conductivity of hBn/Cu plates was higher than that of CFRP. It reduced conduction resistances of plate type heat exchangers. The surface roughness increased in the order of SUS, CFRP, and hBn/Cu plates. The CFD results indicated that increasing the through-plane thermal conductivity of the CFRP plate reduced thermal resistance and increased the heat transfer rate. Additionally, an empirical Nusselt correlation for CFRP plate heat exchangers was developed.