  A computational study has been done to illustrate the effects on two
semi-circular wall heaters placed in a mixed convection rectangular enclosure
containing trapezoidal heated obstacle in presence of magnetic field. The upper
wall moves with a velocity in the positive x-direction. Trapezoidal obstacle is
located in the middle of the cavity and two semi-circular wall heaters are
placed at the bottom wall with fixed distance between them. These two
horizontal walls are kept adiabatic except two semi-circular wall heaters. Two
vertical walls are kept at low temperature and concentration and the
trapezoidal obstacle and two semi-circular walls are kept at high temperature
and concentration. Finite element method is used to solve governing equations.
The present analysis is performed for parameters such as Hartmann number,
Buoyancy ratio and Richardson number. The effects of aforesaid parameters are
explored on the fluid flow and temperature at two semi-circular wall heaters.
The results show that heat transfer rate along right semi-circular wall heater
dominates the left semi-circular wall heater with the increase of both the
parameters Hartmann number and Buoyancy ratio.
