Development of engineering methods for structure-borne noise specification and quantification in aircraft and rotorcraft cabins

飞行器和旋翼飞行器制造商集成了大量负责音调振动的系统，例如（i）在风扇和发动机核心转子频率处产生低频音调分量的飞行器发动机，（ii）在齿轮啮合频率处产生结构承载的中频音调的旋翼飞行器主转子传动装置，（iii）产生中高频音调分量的液压系统和（iv）产生高频谐波的电气部件。这些振动传播到飞机/旋翼机结构中，并传递到内部装饰板，内部装饰板又将噪声辐射到机舱中。这种噪声被称为SBN，已知是飞机/旋翼机内部噪声的主要来源，其影响乘客舒适度，增加机组人员噪声暴露水平并降低他们的沟通能力。然而，如果在产品开发阶段对振动系统、接收结构和它们之间的接口进行了很好的规定和设计，这些恼人的SBN可以得到缓解。该项目的总体目标是开发和验证工程方法，用于预测集成振动系统在飞机/旋翼机机舱中产生的SBN。这些方法将基于现有的SBN方法（即，基于频率的子结构和基于频率的TPA），它们在机械工程界没有广泛传播，因为它们很难在实践中应用。该项目的目标是在因此，专门为航空航天集成系统和结构的调查，扩展和验证这些方法，重点是SBN预测的目标精度所需的复杂程度。这三个工业合作伙伴将获得一个工程工具，以及专门针对其SBN挑战的相关方法和指标。该知识工具箱将使他们能够在产品设计周期的沿着更好地集成SBN设计挑战。**

Aircraft and rotorcraft manufacturers integrate a high number of systems which are responsible for tonal vibrations such as (i) aircraft engines generating low frequency tonal components at Fan and Engines core rotor frequency, (ii) rotorcraft main rotor transmission generating structure-borne mid frequency tones at gear mesh frequencies, (iii) hydraulic system generating mid to high frequency tonal components and (iv) electric components generating high frequency harmonics. These vibrations propagate into the aircraft/rotorcraft structure and are transmitted to the interior trim panels that, in turn, radiate noise into the cabin. This noise, referred to as SBN, is known to be a major source of aircraft/rotorcraft interior noise that affects passengers comfort, increases crew member noise exposure level and decreases their communication ability. However, these annoying SBN could be mitigated if vibrating systems, receiving structures and interfaces between them were well specified and designed during the product development phase. The overall objective of this project is to develop and validate engineering methods for predicting SBN generated in aircraft/rotorcraft cabins by integrated vibrating systems. These methods will be based on existing SBN methods (i.e., Frequency Based Substructuring and Component-based TPA) which are not widely spread in the mechanical engineering community because they are difficult to apply in practice. The objective of this project is in consequence to investigate, extend and validate these methods specifically for aerospace integrated systems and structures focusing on the degree of complexity required for the targeted accuracy on the SBN prediction. The three industrial partners will be provided with an engineering tool together with the relevant methodologies and metrics dedicated to their SBN challenges. This knowledge toolbox will allow them a better engineering integration of SBN design challenges all along the product design cycle.**