Multi-sinusoidal behaviors in thermosolutal vibrational flow through an anisotropic medium with NEPCM in an irregular domain containing an inner isothermal chain

Abstract

This study investigates flow, heat, and mass transfer in an irregular domain containing an isothermal chain filled with an anisotropic porous medium, including nano-encapsulated phase change materials (NEPCMs). The periodic forces in the flow region arise from the sinusoidal structures of the right boundary, the sinusoidal temperature and concentration distributions along the left boundary, and the sinusoidal geometry of the embedded chain. Two heating modes are considered to provide a comprehensive analysis: (1) outer heating, where the embedded chain remains cold, and (2) inner heating, where the chain is exposed to higher temperature distributions. Vibrational flow occurs within an anisotropic porous medium, and the local thermal non-equilibrium model (LTNEM) is applied. This irregular domain is analyzed using a novel Point-in-Polygon Boundary Identification technique in conjunction with the Finite Volume Method. The results show that anisotropic permeability significantly influences flow behavior, causing the fluid to preferentially follow the left diagonal direction, where permeability is highest. This results in elongated or skewed streamlines, deviating from symmetric flow patterns. Additionally, as vibration frequency increases, fluid inertia becomes more dominant relative to viscous forces, resulting in more vigorous oscillatory motion, increased flow pulsations, and rapid variations in velocity profiles.