Numerical analysis of natural convection of thermo-electrically conducting fluids in a square cavity under a constant magnetic field (3rd report, calculated results, frequency characteristics)

In the previous research, the primitive variable methods have been proposed in the numerical scheme of magnetic field of thermo-electrically conducting fluids. The point to be emphasized in the above-mentioned scheme is to satisfy the conservation law of magnetic flux efficiently. In the present paper, we compare the two numerical schemes of magnetic field, namely the cross helicity method and the numerical residual method, concentrating on convergence of Poisson's equation of the velocity and magnetic fields. Moreover, the relationship between the periodicity of low Prandtl number fluids and the convective inhibition effect by Lorentz force must be clarified quantitatively. The frequency characteristics of kinetic energy, enstrophy, palinstrophy and hydromagnetic cross helicity are calculated by the maximum entropy method.