Convective wave front locking for a reaction-diffusion system in a conical flow reactor

We consider reaction-diffusion instabilities in a flow reactor whose cross-section slowly expands with increasing longitudinal coordinate (cone shaped reactor). Due to deceleration of the flow in this reactor, the instability is convective near the inlet to the reactor and absolute at the downstream end. In sustained regimes the two regions are separated by a stationary front. Results of numerical studies of the Brusselator flow model demonstrate that the front locking occurs at the place, where the flow velocity approximately corresponds to that of the transition from convective to absolute instability in a spatially uniform system.