The geometry of this problem is shown in Figure 1(a). The heat source is centrally located on the bottom surface and its length L/3. The cooling is achieved by the two vertical walls. The heat source has constant heat flux while the cooling walls have a constant temperature ; all the other surfaces are adiabatic. Also, it is also assumed that the uniform magnetic field () of constant magnitude is applied, where and are unit vectors in the Cartesian coordinate system. The orientation of the magnetic field form an angle with horizontal axis such that . The electric current and the electromagnetic force are defined by and , respectively.