Aero-engine pipe-casing integration: A flow-strength co-design approach with particle swarm algorithm

To address the high complexity and significant installation costs associated with aircraft engine piping systems, this paper proposes an integrated design approach for piping and engine casings based on structural-functional integration. This method embeds the piping within the casing to achieve a unified design. This paper analyzes the impact of parameter variations on pressure loss through multi-condition numerical simulations of the piping system, thereby deriving flow constraint rules for integrated design. Additionally, multi-physics coupled simulations of the engine casing are conducted to examine the effect of parameter changes on structural strength, leading to the formulation of strength constraint rules for integrated design. Using the summarized constraint rules as limiting conditions, the optimal spatial arrangement of internal piping is determined through automatic optimization based on the particle swarm optimization algorithm. Ultimately, the optimal piping route will be converted into six distinct optimization schemes. These will undergo strength verification using finite element analysis to identify the optimal design solution. The results show that by designing the internal piping as elliptical tubes coaxial with the engine casing, the difference in strength performance between elliptical and circular pipes is only 2%, yet an 18.8% weight reduction is achieved. The integrated structure obtained after the design using the particle swarm algorithm has reasonable flow resistance and strength. This enables a reduction in overall mass while maintaining structural integrity. This integrated design approach combining piping with the engine casing offers new avenues for research in the aerospace field.