  We study a continuous dynamics for a class of Petri nets which allows the
routing at non-free choice places to be determined by priorities rules. We show
that this dynamics can be written in terms of policies which identify the
bottleneck places. We characterize the stationary solutions, and show that they
coincide with the stationary solutions of the discrete dynamics of this class
of Petri nets. We provide numerical experiments on a case study of an emergency
call center, indicating that pathologies of discrete models (oscillations
around a limit different from the stationary limit) vanish by passing to
continuous Petri nets.
