In this study, numerical simulation of hydrothermal behaviour of ethylene glycol based CuO nanofluid in a semi-annulus with a magnetic source is investigated. The non-dimensional governing equations are discretized by radial basis functions in spatial derivatives, and by backward-Euler in temporal derivatives. The effects of dimensionless parameters Hartmann number, Rayleigh number, magnetic number, Eckert number and solid volume fraction are presented both in terms of streamlines, isotherms and vorticity contours, and average Nusselt number through the heated wall. The results show that augmentation in magnetic number accelerates the convective heat transfer at a small Rayleigh number, and at a larger heated inner circle. Convective heat transfer is inhibited with the rise of Hartmann number, and with the increase in Eckert number while it is enhanced with the increase in concentration of nanoparticles and Rayleigh number.