This paper addresses the output regulation of flow systems described by a c
lass of two-time-scale nonlinear PDE systems. Within the framework of singu
lar perturbation, the reduced-order slow model comprised of first-order PDE
s coupled with ODEs is obtained. Based on the numerical approximation techn
ique and the solvability of an inertial manifold, the finite-dimensional no
nlinear model with nonlinear input is developed in this paper. Extending fr
om the geometric control method, the non-distributed nonlinear controller c
an be synthesized. A combination of the state-space internal model control
scheme, the reduced observer-based controller can asymptotically attenuate
the effect of external disturbances. Finally, the developed methodologies a
re successfully applied to the development of a PFR system asscociated with
the cooling coil apparatus. (C) 2001 Elsevier Science Ltd. All rights rese
rved.