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Pipe Routing for Aero-Engine Using Modified MOEA/D

This paper presents a multi-objective pipe routing method based on modified MOEA/D (Multi-objective Evolutionary Algorithm based on Decomposition), to automatically generate non-dominated solutions of pipe layouts in 3D space and aero-engine rotational space. Firstly, a new encoding method suitable for rectilinear routing problems is designed in 3D space. Then, pipe length, pipe installation convenience and the number of bends are formulated as routing objectives, where the obstacle-avoidance constraint is integrated into each objective function. According to the characteristics of pipe routing problems, MOEA/D is modified by integrating a discretization operator and is then used to solve the Pareto set of pipe layouts. Further, the routing method is extended to surface cases to meet paving pipes on rotational surfaces of aero-engines. Finally, pipe routing computations are performed respectively on a 3D model and a simplified aero-engine model, which demonstrates the effectiveness and efficiency of the presented method.