Magnetohydrodynamic natural convection of a ternary nanofluid with variable properties in a wavy trapezoidal enclosure

This study deals with the natural convective ternary hybrid nanofluid flow in a trapezoidal enclosure bounded by a wavy sidewall. The effects of the magnetic field and variable thermophysical properties are also included. Here, the ternary nanofluid is a water-based suspension of copper (Cu), silicon dioxide (SiO2), and multi-walled carbon nanotube nanoparticles. The governing equations with considered physics were first converted into dimensionless equations, which were then transformed into a system suitable for the computational domain. The system is then solved utilizing the efficient compact finite difference method. Flow and heat transfer behaviors are illustrated with volume fraction φ (=0%–2%), inclined wall angle with Y-axis θs (=−15°–20°), Rayleigh number Ra (=103–106), and Hartmann number Ha (=0–70). Interestingly, flow intensity and heat transfer show different behaviors for variable and constant thermophysical properties. As φ increases from 0% to 1.5% the flow intensity decreases, while a small increase is found for the increment from 1.5% to 2%. The converse pattern in the flow field occurs for increasing θs. However, the magnitude of the stream function significantly increases with higher Ra and decreases for increasing Ha. A significant increase in the heat transfer occurs with the increment of Ra and θs and a decrease happens for larger Ha.