Enhanced heat diffusion in triangular wavy enclosures using MoS₂‐water nanofluidics: A Comsol simulation study

Abstract Studying heat diffusion in nanofluid‐filled porous triangular enclosures is essential for advancing scientific and engineering applications such as electronics cooling and metal casting, where efficient thermal regulation is important. With these motives, this investigation explores the heat diffusion and flow characteristics of MoS 2 water nanofluid within a non‐Darcian porous triangular enclosure with a wavy wall. Through contour analysis, the effects of key parameters—including the Darcy number , Rayleigh number , buoyancy parameter , temperature difference , and concentration difference —on fluid flow and thermal distribution are thoroughly examined. The study identifies δT and δC as primary regulators of heat and mass diffusion within the enclosure, while also examining the roles of thermophoretic force , Brownian motion , and nanoparticle volume fraction in determining the average Nusselt number under different wavy wall amplitudes. Moreover, to analyze the impact of surface waviness on fluid flow and heat diffusion, the momentum and thermal distributions are plotted along the horizontal centerline. The primary objective is to analyze how nanoparticle addition and cavity wall shape modifications impact heat diffusion due to thermal performance in nanofluid‐filled enclosures. Using numerical simulations in COMSOL Multiphysics, based on the finite element method (FEM), we solve the governing nonlinear partial differential equations and investigate the patterns of momentum, isothermal, and iso‐concentration contours. A comparative evaluation with existing literature confirms the accuracy and reliability of the results. The findings show that higher Rayleigh numbers create stronger and larger swirling motions, while increased buoyancy leads to smaller but more intense vortices. Interestingly, heat transfer decreases as the walls become wavier, with the best heat transfer occurring when the walls are flat. Increasing the nanoparticle concentration from 0.01 to 0.05 boosts the Nusselt number by approximately 28%, highlighting the effectiveness of MoS₂ nanoparticles in enhancing heat transfer. The heat transfer rate from the plain hot wall is about 38% higher than that from the hot wavy wall, emphasizing the impact of wall geometry on thermal performance. This research provides useful insights for improving heat transfer in nanofluid systems, which is valuable for real‐world engineering applications.