Aeroelastic effect of declining hub to tip ratios on the low-pressure compressor of future UHBR engines

该项目的目标是确定关键的敏感性，这将导致未来大涵道比发动机的新的或增强的气动和气动弹性相互作用，这是通过降低轮毂与尖端的比来实现的。该方法是在综合研究各种风机、风道和IGV变化的基础上，以前所未有的质量评估UHBR风机尾迹激励下压气机第一级的气动弹性灵敏度。本研究的主要目标是：a)以轮毂附近流型和二次流结构为重点，对低轮毂与叶尖比的UHBR风机级低压压气机流入流的气动特性和三维流动结构进行详细研究。b)考虑转子空腔泄漏流。c)考虑风机转子出口、IGV和lpc -转子之间的周期性非定常相互作用。d)新的策略，以避免由于典型的二次流效应而增加前核心发动机叶片的强迫响应和自激。d) e)考虑到当前航空发动机发展的趋势，对典型的激励源进行评估，例如，在进行气动弹性激励后的超高压沸腾式风扇、齿轮传动式涡扇和涡轮螺旋桨飞机。

Aim of the project is the identification of key sensitivities, which will result in new or enhanced aerodynamic and aeroelastic interactions of future large bypass ratios of engines which are achieved through reduced hub-to-tip ratios. The approach is to assess the aeroelastic sensitivity of the first compressor stage with respect to the excitation by UHBR fan wakes in unprecedented quality based on an integrated investigation of various fan, duct- and IGV variations. From this research task, the following sub-goals are derived: a) Aerodynamic characterization and detailed study of three-dimensional flow structure of the inflow to the low-pressure compressor for UHBR fan stages with low hub-to-tip ratiofocussing on the hub near flow regime and secondary flow structures. b) Consideration of the rotor-cavity leakage flow. c) Consideration of the periodic unsteady interaction between fan rotor outlet, IGV and LPC-rotor.d) New Strategies to avoid increased forced-response and self-excitation of the blades in the front core engine due to typical secondary flow effects. d) e) Typical excitation sources are evaluated taking into account current trends in the development of aircraft engines, for example UHBR fans and geared turbofans and turboprops after their aeroelastic excitation and cataloged.