Model based IVHM System for the Solid Rocket Booster

Luchinsky, Dmitry G. and Osipov, Vyatcheslav V. and Smelyanskiy, Vadim N. and Timucin, Dogan A. and Uckun, Serdar (2008) Model based IVHM System for the Solid Rocket Booster. In: 2008 IEEE Aerospace Conference, AC. IEEE Aerospace Conference Proceedings . IEEE, USA, pp. 1-15. ISBN 9781424414871

Abstract

We report progress in the development of a model-based hybrid probabilistic approach to an on-board IVHM for solid rocket boosters (SRBs) that can accommodate the abrupt changes of the model parameters in various nonlinear dynamical off-nominal regimes. The work is related to the ORION mission program. Specifically, a case breach fault for SRBs is considered that takes into account burning a hole through the rocket case, as well as ablation of the nozzle throat under the action of hot gas flow. A high-fidelity model (HFM) of the fault is developed in FLUENT in cylindrical symmetry. The results of the FLUENT simulations are shown to be in good agreement with quasi-stationary approximation and analytical solution of a system of one-dimensional partial differential equations (PDEs) for the gas flow in the combustion chamber and in the hole through the rocket case. The low-dimensional performance model (LDPM) of the fault is derived by integrating a set of one-dimensional PDEs along the axis of the rocket. The LDPM is used to build a model-based fault diagnostic and prognostic (FD&P) algorithm for the case breach fault. In particular, two algorithms are introduced. The first algorithm is based on the self-consistent algorithm that solves the LDPM in a quasi-adiabatic approximation, when the pressure and density follow adiabatically dynamics of the propellant burning, melting and burning of the metal case, ablation and erosion of nozzle and insulator. The second algorithm is based on the dynamical inference method [1]-[3] of the system of stochastic differential equations of the LDPM. The parameters of the HFM model and of the LDPM are tuned to reproduce the results of recent experiments of the rocket firing with the case breach fault in the forward closure. The FD&P is then applied to illustrate real-time diagnostics of the model parameters and prognostics of the SRB internal ballistics. All the algorithms discussed in this paper were verified using experimental data as will be discussed elsewhere. The accuracy of the algorithm and the possibility of its application to FD&P for other SRB fault modes are discussed.