Proc. Japan Acad. Ser. A Math. Sci. 83 (1), 1-4, (January 2007) DOI: 10.3792/pjaa.83.1
KEYWORDS: Parallel-flow heat exchanger equation, boundary input, reachability, $C_0$-semigroup, characteristic differential equation, 93C20, 93B99
This paper is concerned with the problem of reachability of parallel-flow heat exchanger equations with boundary inputs. It is shown that the system with boundary inputs is formulated as a boundary control system which is well-defined in the sense of Curtain and Zwart (1995), and further that it is reachable through a concrete expression of the solution. In addition, the reachable subspace is given for the case where only one boundary input is added to the system.
