Abstract Aeroelastic behavior of aircraft is significantly affected by the presence of engines mounted under the wings. Powered engines influence the unsteady aerodynamics on the one hand and lead to additional unsteady forces due to thrust vector oscillations on the other hand. This work focuses on the incorporation of aerodynamic engine effects into a small disturbance CFD framework to enhance the modeling accuracy of unsteady aerodynamics of aircraft. The effects are numerically modeled by mimicking physically reasonable flow conditions at the intake and nozzle planes of the engine nacelle. Subsequently, the influence of the engine effects on the flutter behavior of an aircraft is studied employing the small-disturbance-CFD-based flutter analysis. The basis for the investigation is the Common Research Model, which represents a modern transonic commercial airliner with a cruise Mach number of 0.85. Two configurations are considered: aircraft with passive engines represented by flow-through nacelles and aircraft with powered engines, where the novel small disturbance engine model is applied. The results are compared in terms of the flutter trends and the predicted flutter boundary. Furthermore, the impact of the modal induced thrust oscillations on the aeroelastic behavior of the aircraft is discussed.

中文翻译：

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与飞机颤振研究相关的小扰动 CFD 的发动机建模

摘要 安装在机翼下的发动机会显着影响飞机的气动弹性行为。动力发动机一方面影响不稳定的空气动力学，另一方面由于推力矢量振荡导致额外的不稳定力。这项工作的重点是将空气动力学发动机效应纳入小扰动 CFD 框架，以提高飞机非定常空气动力学的建模精度。通过模拟发动机短舱的进气口和喷嘴平面处物理上合理的流动条件，对这些影响进行了数值模拟。随后，采用基于小扰动 CFD 的颤振分析来研究发动机效应对飞机颤振行为的影响。调查的基础是共同研究模型，它代表了巡航马赫数为 0.85 的现代跨音速商业客机。考虑了两种配置：带有以流通式短舱为代表的被动发动机的飞机和带有动力发动机的飞机，其中应用了新颖的小扰动发动机模型。根据颤振趋势和预测的颤振边界对结果进行比较。此外，讨论了模态引起的推力振荡对飞机气动弹性行为的影响。