  We present several hydrodynamical simulations of thermonuclear supernovae
dealing with multiple delayed detonations. The calculations were carried out in
three dimensions, making possible to study the influence of geometry of the
flame front in two aspects. First, the evolution of its fractal dimension
during the deflagration phase has been followed until a critical value is
reached such that the deflagration may turn into a detonation. Second, as the
resulting detonation could probably be scattered through the flame, the effect
of its initial location on the detonation propagation, final energetics and
nucleosynthesis has been explored.
