Research on horizontal topology optimization fins in latent heat storage unit

Abstract

Adding fin structures enhances the heat transfer performance of latent thermal energy storage (LHTES) units. Current research on fin optimization focuses mainly on single or multiple fin parameters, but fin optimization requires considering the interdependencies of multiple parameters. Topology optimization can generate an optimized fin structure directly under specific conditions, simplifying the process and improving performance. This study investigates the effects of penalty index (1–9), filter radius (0.5–3 mm), projection slope (1–9), and projection point (0.1–0.9) on topology-optimized (TO) horizontal fins using variable density method-based continuous topology optimization theory. Results show that selecting appropriate design parameters is crucial for effective fin optimization. Comparing annular fins and TO horizontal fins reveals that TO horizontal fins significantly reduce melting time by up to 65.68 %. Increasing the volume fraction of TO horizontal fins improves melting efficiency to a certain limit, with diminishing returns as the fraction increases. A fin volume fraction of 12.5 % offers the best balance between efficiency and heat storage capacity. Two simplified schemes are proposed: removing thin fins and tips (Simplified Scheme 1) has minimal impact on heat transfer while reducing melting time by 2.5 %, whereas eliminating secondary bifurcation structures (Simplified Scheme 2) slightly decreases performance, increasing melting time by 7.6 %.