Numerical Analysis of MHD‐Mixed Convection and Melting of NEPCM in a Porous Triangular Cavity With Rotating Cylinder

ABSTRACT Researchers are driven to explore alternative and environmentally friendly energy sources due to the significant impacts of environmental degradation. Thermal energy storage utilizing phase change materials (PCMs) has developed as a novel option for mitigating environmental pollution. This study numerically proposes an approach to enhance the energy storing and heat transmission rates of PCMs in a triangular space. Within the space, there is a rotating cylinder that maintains a consistent speed, resulting in the production of forced heat transfer. Natural convection occurs due to the thermal gradient between the space's partially hot left wall and the remaining cold walls. To achieve optimal outcomes, an investigation was performed to assess the impact of various elements on mixed convection in the given region. The elements that need to be considered are the Reynolds number Re (10–100), which represents the speed of the inner cylinder, the Darcy number represents the permeability Da (10 −5 –10 −2 ), the Hartmann number Ha (0–100), which represents the intensity of the magnetic field, and the volumetric percentage of the nanoparticles ɸ (0–0.08). The obtained findings demonstrated a notable augmentation in heat transfer rates when the Da value increased and the position of the heated section on the left wall was altered. Conversely, the heat transmission rates decreased with a rise in Ha and ɸ . The study found that increasing the values of Ha and ɸ to their maximum levels resulted in a reduction of 20% and 15% in Nu avg , respectively. By raising Da and shifting the heated area of the left wall lower, Nu avg experienced a significant rise of 320% and 162.5%, respectively.