Numerical simulation and experimental characterization of ZrB ₂ -HfB ₂ ceramic composite for microchannel heat exchanger applications

This study investigates the potential of advanced ceramics, specifically ZrB 2 -HfB 2 reinforced with silicon carbide and carbon fibers (ZHSC f ), as alternatives to metals in microchannel heat exchangers. This research leverages the synergistic combination of ZrB 2 , HfB 2 , SiC, and C f to enhance thermal performance, overcoming the limitations of monolithic ceramics. The primary objective is to evaluate the thermal efficiency of ZrB 2 -HfB 2 -SiC-C f composite and compare their performance with Al 2 O 3 and TiB 2 -SiC for microchannel heat exchanger applications. The (ZrB 2 -HfB 2 -SiC-C f ) composite was fabricated using spark plasma sintering and comprehensively characterized for its phase composition, microstructure, and thermal properties. A computational analysis employing the finite element method (Ansys 2024 R1) was conducted to evaluate the thermal performance of the ZrB 2 -HfB 2 -SiC-C f microchannel heat exchanger, comparing results against those of Al 2 O 3 and TiB 2 -SiC. The findings reveal that at a mass flow rate of 20.4 kg/h, ZrB 2 -HfB 2 -SiC-C f offers a 52% increase in heat transfer over Al 2 O 3 and 26% over TiB 2 -SiC, similarly for the same mass flow rate the effectiveness of ZHSC f increases by 46% over Al 2 O3 and 26% over TiB 2 -SiC. Combining high thermal conductivity and uniform microstructure ensures efficient heat dissipation and reduces thermal resistance, making ZrB 2 -HfB 2 -SiC-C f composite a highly effective material for microchannel heat exchanger applications.