Radial magnetic field distribution on the solar surface with a strong dipole at the equator and four weaker dipoles at higher latitudes in the northern hemisphere (left). The two thick black lines represent the equatorial and parasitic dipole polarity inversion lines. Longitudinal 2D Sections of the grid at Φ = −175° and 5° after the relaxation (right). For more details, see Sect. 2.4. In both panels, the simulation grid is represented with thin black lines.