Trajectory analysis of nonisothermal tubular reactor nonlinear models

The existence and uniqueness of the state trajectories (temperature and rea ctant concentration) are analyzed for nonisothermal plug flow and axial dis persion tubular reactor models. It is mainly shown that these trajectories exist on the whole (nonnegative real) time axis and the set of all physical ly feasible state values is invariant under the dynamics equations. The mai n nonlinearity in the model originates from the Arrhenius-type kinetics ter m in the model equations. The analysis essentially uses Lipschitz and dissi pativity properties of the nonlinear operator involved in the dynamics and the concept of state trajectory positivity. (C) 2001 Elsevier Science B.V. All rights reserved.