Propulsion system structural response to variation in aircraft architecture

Meeting future commercial sustainable aviation goals will require aircraft architectural configurations and propulsion systems that deviate from those currently employed today. Developing or selecting an optimal propulsion system solution for integration with novel aircraft configurations necessitates an understanding of how propulsion system performance and design requirements are impacted by such architectural changes at the aircraft level. With a focus on the structural characteristics of the propulsion system, this paper details how relevant architectural changes (mass, stiffness and location of powerplant and airframe integration) impact the key structural response of the propulsion system (powerplant deformation, sizing loads and dynamic behavior).

A sensitivity study employing Taguchi Design of Experiments approach has been performed to identify the most dominant aircraft architectural parameters, and quantify how they impact the key structural performance metrics that inform propulsion system design. A whole aircraft coupled aerodynamic (DLM) – Flight Dynamics (FD) – Structural Dynamics (SD) airframe model has been generated, and integrated with a higher fidelity propulsion system idealization, for the purpose of acquiring key structural performance metrics under a range of static and dynamic load cases.

The study concluded that, for a tube and wing aircraft configuration, the location of the powerplant under the wing had the most significant impact on airframe sizing loads, power plant sizing loads, and internal power plant deformations. Powerplant location combined with mass also had a significant impact on the dynamic response (natural frequencies) of the coupled propulsion system and airframe.