Akademik Veri Yönetim Sistemi
Applied Thermal Engineering, cilt.281, 2025 (SCI-Expanded, Scopus)
Enhancing heat transfer efficiency is crucial for improving the performance of systems designed for heat dissipation and thermal storage. Phase change materials (PCMs) offer favorable thermal characteristics but are hindered by inherently slow melting rates, a limitation this study seeks to address. This study introduces a novel approach that utilizes mechanical mixing to induce forced convection within a PCM-filled cavity. Experimental investigations were performed, where forced convection was introduced through liquid mixing at rotational speeds of 5, 25, and 100 rpm. For numerical studies, the enthalpy–porosity method, incorporating the Boussinesq approximation, is used. Experimental findings indicate that higher rotational speeds shorten the melting duration by up to 22 % (reducing it to 32 h) and increase the final liquid fraction by approximately 14 %, enabling complete melting compared with the non-rotating case. Moreover, mixing effectively reduced internal temperature gradients, lowering the maximum temperature from 68 °C to 45 °C and promoting a more uniform thermal distribution. At lower rotational speeds, the melting duration decreased by only about 10 %, with negligible impact on the final liquid fraction. The heat generation rate also strongly influenced melting performance. Experimental and validated numerical results, obtained with a Cmush value of 10⁶, showed acceptable agreement. Both approaches confirmed that at 40 W, 86 % of the PCM melted within 43 h, whereas at 20 W only 26 % melted in the same period. These findings establish mechanical mixing as a practical and effective strategy to overcome PCM’s slow melting limitation, thereby enhancing the applicability of PCMs in thermal management systems.