Parameter fault diagnosis in heat exchange networks with distributed time delay

This paper deals with parameter fault diagnosis in heat exchange networks (HENs) joining and splitting connections where the change transfer coefficient is considered as fault. The oriented model of HEN elements was developed based on equivalent LTI realization distributed delay models. Signed Directed Graph (SDG) method used to derive observability conditions. presence faults induces bilinear fault-input terms into system model. Thus, a nonlinear adaptive observer proposed for diagnosis. To verify validate method, case study presented. simulation results show that observers are successfully detecting estimating unknown states.