Vibration-induced heat transfer enhancement in additively manufactured Kelvin metal foam

Abstract

Compact porous media heat exchanger presents a promising solution for advanced thermal management in vehicles. However, their heat transfer performance under inevitably vibration conditions is not yet well understood. In this regard, this paper studies the heat transfer enhancement mechanisms of Kelvin metal foam heat exchanger induced by vibration via experiments and pore scale simulations. An 80 mm × 270 mm × 210 mm full scale Kelvin metal foam heat exchanger was fabricated using AlSi10Mg powder through selected laser melting (SLM) additive manufacturing. The effect of vibration amplitude and frequency on its performance was experimentally studied using a wind tunnel with a vibration platform. Results indicate that (i) vibration can improve the performance of the heat exchanger, with a maximum effective heat transfer coefficient (EHTC) of 1.56 kW/(m²·K), a 13.93 % increase over the 1.37 kW/(m²·K) observed without vibration; (ii) The Analysis of Variance (ANOVA) reveals that amplitude and frequency similarly affect its heat transfer performance within the vibration range of 1–5 mm and 20–40 Hz; (iii) Vibration enhances heat transfer by breaking the flow boundary layer. The heat transfer coefficient varies periodically with vibration and increases as vibration amplitude rises. Notably, the change frequency of heat transfer coefficient is twice that of the vibration frequency. This work quantitatively analyzes how vibration improves the performance of metal foam heat exchanger and offers significant data reference for their practical applications.