A Multidisciplinary Model-Based Engine Rotor Integrity Assessment Approach Derived from System Safety Requirements

Rotor integrity is one of the most critical factors of aero-engine safety. It involves multiple strongly coupling disciplines, including engine overall thermodynamics, secondary air system flow distribution, rotor cavity flow pattern, heat transfer, and stress analysis. However, published research barely discusses the inter-relationships between these disciplines, which may be unsatisfactory for advanced aero-engines to evaluate the rotor’s overspeed and burst margin. To address this problem, this paper proposes a tightly coupled rotor integrity assessment approach based on a multidisciplinary aero-engine model. Firstly, this paper analyzes the safety objective and development trend of the airworthiness requirement to clarify the modeling demands. The risk-based criterion is suggested to rotor integrity assessment to take engine system safety requirements into account. Besides, this paper establishes a model-based rotor integrity assessment approach by detailed analyzing the inter-relationships between the related disciplines. Combing with the multidisciplinary model, this paper also introduces uncertainty quantification and safety analysis approaches to rotor integrity assessment to evaluate the engine-level impacts. Further, the proposed model-based assessment approach is applied to a turbine rotor loss of load assessment case. The result confirms the necessity to consider the multidisciplinary impacts during rotor integrity assessment, and validates the approach’s ability in calculating safety-critical parameters during the failure-induced transient state. The model-based approach provides an effective method of compliance in addition to conventional costly tests, which may be beneficial for ensuring advanced engine safety and airworthiness certification.