Abstract
This paper is concerned with the problem of enhancing the stability of a parallel-flow heat exchanger equation with diffusive terms, under boundary control and boundary observation. By introducing two new variables, the system is expressed as two decoupled subsystems, where each subsystem is exponentially stable. In order to enhance the stability of the whole system, we use a backstepping method to construct infinite-dimensional observer-based controllers for each subsystem. The Lyapunov method is successfully applied to prove the closed-loop stability with the controller. This paper gives the controller design for the case of collocated sensor and actuator as well as for the anticollocated case.
