Solidification & Melting: PCM Melting Rate Via Internal Fin and Nanoparticles

PCM Melting Rate Enhancement via Internal Fin and Nanoparticles — CFD Simulation in ANSYS Fluent

Introduction

This project simulates the melting behavior of a phase change material (PCM) inside a two-dimensional cavity enhanced with an internal fin and dispersed nanoparticles, based on the methodology presented in a reference study on enhancing PCM melting rate through internal fins and nanoparticles. The simulation investigates how the combined effect of a conductive fin and CuO nanoparticle dispersion within paraffin wax accelerates the melting process compared to a plain PCM cavity.

Geometry and Mesh

The cavity geometry, with a width of W = 20 mm and filled with paraffin wax, was created in Design Modeler. The domain was meshed in ANSYS Meshing, generating approximately 10,000 structured cells.

Methodology

Gravitational acceleration was included in the simulation to capture buoyancy-driven natural convection effects during melting. Since several thermophysical properties of the PCM in the reference study were originally defined through user-defined functions, these properties were instead extracted at key reference points and represented using a polynomial linear model. The material properties used correspond to a mixture of paraffin wax and CuO nanoparticles. The left wall and the internal fin were maintained at a constant temperature of 350 K, while the right wall was held at 300 K, with all remaining walls treated as insulated. The case examined corresponds to a fin-to-cavity width ratio (w/W) of 0.5.

Results and Conclusion

After 375 seconds of simulation time, results show that heat is progressively transferred from the left wall toward the right wall due to the imposed temperature gradient, with the PCM undergoing a phase change as local temperatures reach the melting point. By the end of the simulation, 35.65% of the PCM had melted, illustrating the combined influence of the internal fin and nanoparticle enhancement on accelerating the melting process within the cavity.