Complex pattern development in a plug–flow reactor

Abstract

In this paper we examine the behaviour of an oscillating chemical reaction in a plug–flow reactor. Such systems are capable of displaying stationary concentration patterns. It is demonstrated here that, experimentally, small changes in flow velocity can lead to large changes in system response. At flow velocities close to the critical velocity for the maintenance of stationary patterns, a new type of complex pattern is observed. Stationary patterns are found to appear after a transition period, the length of which depends sensitively on the flow rate. A possible mechanism is discussed, involving fluctuations of the fluid phase at the boundary and interactions of species with the packing material. These interactions may help to explain the stability of the stationary patterns once established in experiments.