Magnetic energy versus time for a kinematic dynamo simulation for the B2 case (ζ₀ = 0.15). The solid line corresponds to the full dynamo problem in which the induction equation is solved using the complete velocity field. The dotted line corresponds to the dynamo that is driven by the small-scale flow (only modes such that k_H > 10 are retained in the velocity field that is used to solve the induction equation), whilst the dash-dotted line corresponds to the case in which only the large-scale flow (where only modes such that k_H < 10 are retained) has been used.