Numerical investigation of convective heat and mass transfer in a trapezoidal cavity filled with ternary hybrid nanofluid and a central obstacle

This study investigates the combined heat and mass transfer characteristics in a trapezoidal cavity saturated by ternary hybrid nanofluid with a circular obstacle, considering the effects of key dimensionless parameters, including the buoyancy ratio ( N ), obstacle radius ( r 0 ), Rayleigh number (Ra), Lewis number (Le), and nanoparticle volume fraction ( ϕ ). A numerical approach is employed to analyze the streamlines, isotherms, and concentration contours under varying conditions. The results indicate that increasing N enhances convective transport, while negative values lead to flow instability. Larger obstacle sizes significantly impact circulation patterns, affecting both heat and mass transfer rates. Higher Ra values intensify convection, improving thermal and solutal transport. Additionally, increasing Le suppresses mass diffusion, while higher nanoparticle concentrations enhance thermal conductivity but may hinder convective flow. These findings provide valuable insights into optimizing convective transport in enclosed systems, relevant to industrial and environmental applications.