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The following dynamo model will be discussed and hopefully numerical results will be presented. Let $A$ be the vector potential for the axisymmetric poloidal field, and $B,$ the toroidal field. $B$ is generated by a shear in the angular velocity acting on $A$ in a thin layer located in the lower solar convection zone. If in this layer $B$ exceeds a critical value for a certain value of theta (the polar angle), eruption occurs. The flux tube is assumed to rise radially and to surface as a magnetic ring doublet. The rates of eruption of the ensemble of these doublets constitute the source term of the equation for $\partial A / \partial t$ that regenerates the poloidal field. The poloidal field generated in the solar surface layers reaches the lower solar convection by transport due to meridional motions and by diffusion. The meridional motions being considered are the superposition of a one-cell velocity field that rises at the equator and sinks at the poles and of a two-cell motion that rises at the equator and poles and sinks at mid latitudes. Meridional motions of this type have a strong theoretical and observational support.
