Graphene-based composites fins: CFD simulations and comparison with copper and aluminum

High thermal conductivity composites, such as graphene-based composites, represent a promising alternative to traditional materials in heat exchange devices. This article presents computational fluid dynamics simulations of a finned copper device subjected to laminar flow. The fins are made of multilayer graphene sheets (GS) impregnated with polydimethylsiloxane. Three fin configurations (annular, rectangular, and pin) were simulated to identify the most efficient design. The device is heated by a 100 W heat source, and heat is removed by cold air flow (inlet temperature 20 °C, inlet velocity from 0.1 m/s to 3 m/s). Thermal contact between fin and base is modeled in four ways: a) ideal case (perfect contact); b) intermediate case (thermal paste); c) worst case (air layer); d) realistic case (porous thermal paste). Simulations were also conducted with copper and aluminum fins for comparison. The results show that the annular fin configuration is the most efficient. Under identical thermal contact conditions, composite fins (70 wt% GS) achieve efficiency comparable to copper and outperform aluminum fins. These findings suggest that graphene-based composite fins are a viable alternative, offering advantages like weight reduction, cost savings, and corrosion resistance. Future experimental work will validate these results.