Justification of Prandtl Ansatz for MHD Boundary Layer

The paper aims to justify the high Reynolds numbers limit for the magnetohydrodynamics system with Prandtl boundary layer expansion when no-slip boundary condition is imposed on a velocity field and perfectly conducting wall condition on a magnetic field. Under the assumption that the viscosity and resistivity coefficients are of the same order and the initial tangential magnetic field on the boundary is not degenerate, we justify the validity of the Prandtl boundary layer expansion and give an $L^\infty$ estimate on the error by multiscale analysis.