---

Abstract: In the papers published on compressible fluid using Pseudo Bond Graph approach, isentropic flow is assumed. However in a converging- diverging nozzle, for a specific pressure ratio, the assumption of isentropic flow is invalid. For the purpose of considering normal shock effects, this paper introduces a new field (NIKE-field) to the pseudo bond graph. The output of the new field can be also used to determine normal shock position and to extract momentum equation as well. In the following, the methodology developed in this paper has been applied a simple pedagogic example. Simulation result is validated by comparison with the analytical result. As the new field can be modeled non-isentropic flow, it can be used to for modeling rockets motors and thrusters in transient state. One of another advantage of new field (NIKE-field) is that it can be easily used in many software applications like MS1, SYMBOLS2000 and 20SIM®; therefore, With regard to the systematic derivation of a mathematical model from a bond graph in these softwares, there is no need to derive any state equations and their solutions.

---

In this paper, a new model for degradation has been introduced to cover multiple dynamics for prognostics purposes. Firstly, Augmented Global Analytical Redundancy Relations (AGARRs) have been introduced to track system’s health constantly. Whenever an inconsistency appears, the proposed algorithm checks the Mode Change Signature Matrix (MCSM) and decides if inconsistency is due to a change in modes or an existence of a faulty component. Using Mode Dependent Fault Signature Matrix (MD-FSM), a Set of Candidate Faults will be generated and fed into PF part to estimate the actual fault and parameters of the degradation model. Finally, by applying obtained degradation model, Remaining Useful Lifetime (RUL) will be estimated.