Optimized thermal storage in a heat exchanger with paraffin nano enhanced PCM and rectangular fins

This research paper examines the melting process of a nano enhanced phase change material (nePCM) based on paraffin wax and alumina nanoparticles in an insulated heat exchanger consisting of heated double inner tubes, surrounded by the nePCM that stores the acquired latent thermal energy and melts. The article investigates factors that directly influence the efficiency of this system, for instance, fins emplacement, along with the volume fraction 2% ≤ φ ≤ 6% of the nanoparticles and their impact on the melting process, temperature distribution, as well as the energy stored. Through a program based on the Finite Element Method, four different structures are considered to assess their thermal performance. The results demonstrate the importance of fin location, especially in the central region of the heat exchanger. As heat distribution predominantly shifts toward the system’s surface and around the heating tubes, strategically arranging fins between these tubes becomes critical for optimal performance. Notably, the utilization of a continuously connected heating system (configuration c) has shown to be highly efficient in improving heat transfer, yielding rapid melting and optimized thermal storage, followed by the performance of configuration (d) with inclined discontinuous inclined fins, particularly at φ = 4%, considering it the optimal concentration of the nanoparticles.