Investigation of Finned heat pipe on compact heat exchanger in waste heat recovery application – Experimental analysis

Department of Aeronautical Engineering, Kalasalingam Academy of Research and Education, Krishnankoil, Tamilnadu 626126, India.

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Published online: 26 September 2025

Abstract

Heat exchangers are essential components in a wide range of industrial processes by enabling efficient thermal energy transfer among fluids, significantly impacting overall system performance. This study examines the effective heat transfer of a concentric tube heat exchanger enhanced with finned heat pipes, aiming to optimize heat energy recovery and improve energy efficiency. Experimental investigations are conducted under varying inlet temperatures (70°C to 90°C) and fluid flow rates (0.0138 to 0.0555 kg/s) to evaluate key performance metrics, including heat transfer rates, heat transfer coefficients, and system effectiveness. Results reveal that higher inlet temperatures and mass flow rates significantly boost thermal performance, achieving a maximum heat transfer coefficient of 2211.91 W/m²°C and effectiveness of 39.1% at 90°C and 0.0555 kg/s, similarly the observed Reynolds number for this condition is 2771 this shows flow is laminar and resulting in uniform heat transfer within the heat exchanger. The integration of finned heat pipes enhances maximum contact surface area and thermal gradients with flowing fluids and heat pipe, thus enabling superior energy recovery compared to conventional systems. These findings underscore the potential of finned heat pipe technology for sustainable and efficient thermal management solutions in industrial waste heat recovery systems to enhance the affordable clean energy and minimize the climate action.