Heat transfer enhancement in a nano encapsulated PCM-water filled square cavity with flexible fin

The emphasis of this study is on a numerical study of the convective flow within a square cavity. A fin is attached to the heated left wall of the cavity, which is filled with a novel hybrid nanofluid. This hybrid nanofluid is composed of water combined with nano encapsulated phase change material (PCM). These capsules consist of a polyurethane shell encapsulating a nonadecane core, which exhibits a remarkable phase change behavior capable of efficiently preserving and releasing a significant amount of latent heat. To model this phenomenon, the governing equations are formulated in the Arbitrary Lagrangian-Eulerian (ALE) framework for both the fluid and fin domains. The Finite Element Method (FEM) is then used to solve these equations. The controlling parameters under consideration are the volume fraction of capsules (0.0 <= phi <= 0.05), the Young's modulus of the fin (10(9) <= E <= 10(11)), the Rayleigh number (10(5) <= Ra <= 10(6)), the Stefan number (0.2 <= Ste <= 0.6), the fusion temperature of the core (0.1 <= theta(f) <= 0.3) and the thermal conductivity ratio (2 <= k(p) <= 100). The study reveals a significant enhancement in the steady state heat transfer rate compared to scenarios without fin. A significant enhancement in thermal performance is evident only with the concurrent increase in nanocapsules concentration and the introduction of the fin. The augmentation in thermal performance is further amplified with an increase in the core fusion temperature, an increase in the thermal conductivity ratio, or a decrease in the Stefan number. The integration of a thin and flexible fin, coupled with the incorporation of nano-encapsulated PCM, holds promise for cooling applications across multiple industries by effectively enhancing thermal performance.