In the current investigation, a (TiO 2–Ag/water) hybrid nanofluid (NF), saturated porous medium filled wavy-walled enclosure, and an unstable magneto-mixed convective flow are examined. Heat radiation (Rd) is present with the constant magnetic field (B0), and the cavity, which is partially heated from its bottom wall and cooled from its wavy-left and right walls, contains a square solid block that is solidly surrounded on all sides. The governing PDEs, which are represented in terms of stream function, temperature, and nanoparticle volume percent, are numerically solved using a finite volume technique. It is discovered that as the dimensionless heat source length (B) rises, the streamlines' strength marginally changes while the isotherms in the wavy porous cavity grow increasingly obvious. The results show that increasing the number of undulations and hybrid NF generally produces a higher average Nusselt number …