Life cycle maintenance decision of civil aero-engine problem decoupling considering structural correlation

To reduce the maintenance cost of a civil aero-engine, rational life cycle maintenance decisions need to be developed, including the determination of maintenance intervals and the scope of maintenance work. To achieve the goal of the lowest total maintenance cost, a life cycle maintenance decision optimization model for civil aero-engines based on structural correlation is established. In this model, to reduce the size of the solution space, the maintenance interval and the maintenance work scope are decoupled, and the optimal maintenance strategy is introduced to determine the maintenance work scope. An improved particle swarm optimization algorithm is used to search for the global optimal solution of the model. The effectiveness of the model is verified through numerical experiments on 17 modules, 20 life limited parts, and problems below the scale of 60,000 flight cycle conditions. The experimental results show that the model can obtain a better solution in a shorter time and applies to the aero-engine life cycle maintenance decision-making problem.