Natural Convection within Inversed T-Shaped Enclosure Filled by Nano-Enhanced Phase Change Material: Numerical...

Area of Science:

• Thermodynamics and Heat Transfer
• Nanomaterials Science
• Computational Fluid Dynamics

Background:

• Energy saving is a critical global concern, driving research into advanced materials and methods.
• Nano-enhanced phase change materials (NePCM) offer promising solutions for efficient thermal energy storage and management.
• Understanding heat transfer in complex geometries under various physical conditions is essential for optimizing NePCM applications.

Purpose of the Study:

• To numerically simulate natural convection of NePCM within an inverse T-shaped enclosure.
• To investigate the influence of key parameters, including Rayleigh number (Ra), Darcy number (Da), nanoparticle volume fraction (φ), and Hartmann number (Ha), on heat transfer performance.
• To quantify the impact of these parameters on local and average Nusselt numbers.

Main Methods:

• The study employed a higher-order Galerkin finite element method (GFEM) for numerical simulation.
• Governing equations for natural convection flow with NePCM were solved.
• Parametric analysis was conducted for Da (10⁻²–10⁻⁵), Ra (10³–10⁶), φ (0–0.08), and Ha (0–100).

Main Results:

• Rayleigh number (Ra) and Darcy number (Da) were found to significantly impact both local and average Nusselt numbers.
• Increasing Ra from 10³ to 10⁶ resulted in a 740% enhancement in the maximum average Nusselt number.
• Increasing Da from 10⁻⁵ to 10⁻² led to a 360% enhancement in both maximum average and local Nusselt numbers, while other parameters showed negligible effects.

Conclusions:

• The buoyancy force (Ra) and porous media permeability (Da) are dominant factors controlling heat transfer in NePCM-filled inverse T-shaped enclosures.
• Optimizing Ra and Da is crucial for maximizing thermal performance in such systems.
• The findings provide valuable insights for designing efficient energy-saving systems utilizing NePCM.