Sonic Mach number solutions obtained starting with a 5 Myr old superbubble ansatz (left) and with a 10 Myr old superbubble ansatz (right). The simulations have converged after 0.5 Myr (left) and 0.7 Myr (right). The three rows show different slices. Note that the figure bounding box is kept the same for all slices: the right panels are not a zoom of the left panels but a simulation of an older cluster.