MHD thermosolutal convection in nanofluids with Soret and Dufour effects using a hybrid MRT-LBM–FDM approach

Abstract

This study develops a hybrid numerical model to simulate magneto-thermo-solutal convection in nanofluids, incorporating the Soret and Dufour effects. The model combines the Multiple Relaxation Time Lattice Boltzmann Method (MRT-LBM) for fluid flow, the BGK-LBM for solving the magnetic induction equation, and the Finite Difference Method (FDM) for heat and mass transport. Simulations are performed for Cu–H 2 O and Al 2 O 3 –H 2 O nanofluids in a lid-driven cavity, with parametric analyses of the Hartmann number ([Formula: see text]) and cross-diffusion numbers ([Formula: see text]), under aiding and opposing buoyancy conditions. Results show that Cu–H 2 O provides better thermal and solutal performance than Al 2 O 3 –H 2 O at low [Formula: see text] and [Formula: see text]. However, magnetic damping and opposing buoyancy ([Formula: see text]) reduce or reverse this advantage. The proposed model effectively captures the complex interplay between magnetic, thermal and solutal effects, offering a robust framework for multi-physics transport simulations in nanofluids.