Integration of absorbing materials in composite structures for turbofan engine noise reduction

创新的制造技术为创造满足复杂和限制性飞机发动机规格的新材料带来了前所未有的机会。这一为期五年的重大合作项目带来了技术解决方案，旨在创造新型、多功能的声学材料来取代传统的发动机衬套。这项研究的动机是国际监管委员会对飞机噪音、二氧化碳和氮氧化物排放提出了越来越严格的要求。为了对新的、高效的发动机配置作出充分的响应，人们寻求在较宽的频率范围内进行吸声。该项目由国际高科技集团和领先的设备制造商赛峰集团进行。研究了三种新的颠覆性技术，以生产由高机械性能飞行认证树脂制成的功能化光结构。(1)使用最先进的聚合物复合材料添加剂制造来生产微网状材料。(2)使用一种巧妙的浇铸方法，用高性能聚合物复制被认为具有优异声学性能的低机械性能泡沫。(3)采用添加法制备了具有扭转腔的奇异谐振器材料，探索了面层织构和原始穿孔。将对发动机部件中集成声学材料的各种设计进行适航性测试。典型尺寸的圆柱形样机将在特殊的发动机试验台上进行内部流动测试。最终的结果是一个全面的技术演示，新的声学衬垫将被集成到Leap发动机复合材料风扇机箱中。这个雄心勃勃的项目是一个独特的机会，可以培训36名高素质的人员解决多学科的行业问题。他们将致力于开发先进的技术和科学诀窍，以及对加拿大工业有用的国际软技能。这种创新的声学材料有望在下一代超高旁路比发动机上实现。预计将通过赛峰机舱和赛峰通风系统，最终通过赛峰着陆系统，应用于加拿大制造的飞机。

Innovative manufacturing technologies bring unprecedented opportunities for creating new materials that meetcomplex and restrictive aircraft engines specifications. This major five-year collaborative project bringstechnological solutions for creating novel, multifunction acoustic materials to replace traditional engine liners.The research is motivated by increasingly stringent requirements from international regulatory boards onaircraft noise, CO2 and NOx emissions. Sound absorption over a broad frequency range is sought in order torespond adequately to new, high-efficiency engine configurations. The project is carried out by ÉcolePolytechnique de Montréal and Safran, an international high-tech group and leading equipment manufacturer.Three new disruptive technologies are investigated to produce functionalized light structures made of highmechanical performance flight-certified resins. (1) Micro-meshed materials are produced using state-of-the-artadditive manufacturing of polymeric composites. (2) Low mechanical performance foams that are recognizedfor having excellent acoustic properties are replicated with high-performance polymers using an ingeniouscasting method. (3) Exotic resonator materials with twisted cavities are made through additive manufacturing.Face sheet textures and original perforations will be explored. Various designs for integrating acousticmaterials in engine components will be tested for airworthiness. Representative-size cylindrical prototypes willbe tested with internal flow on a special engine test platform. The final outcome is a full scale technologicaldemonstrator, where novel acoustic liners will be integrated to a LEAP engine composite fan case.This ambitious project is a unique opportunity to train 36 highly qualified personnel on multidisciplinaryindustry problems. They will engage in developing advanced technical and scientific know-how andinternational soft skills useful to the Canadian industry. Implementation of the innovative acoustic materials isforeseen on next generation ultra-high bypass ratio engines. Devired applications to Canadian-made aircraftsare expected through Safran Nacelles and Safran Ventilation Systems, and eventually Safran Landing Systems.