Objectives

Context and global objectives

Mitigating aircraft noise on both modern and future aircraft is a significant challenge for the EU, considering the increase of air traffic and extension of urban areas together with the increasing public health concern. Aircraft noise results from the combination of engine noise, significantly reduced after decades of intensive research, and airframe noise, mostly generated by landing gears (LGs) and high-lift devices (HLDs). Strong integration constraints imposed by other considerations than acoustics and our limited knowledge of the complex flow physics mechanisms generating airframe noise have so far limited the development of noise reduction technologies (NRTs) on airframe components such as LGs and HLDs. Direct design of low-noise airframe components based on multi-disciplinary criteria (including acoustics), remains a challenge as well.

Therefore, the primary goal of INVENTOR is to better understand the physics of noise generated by LGs and HLDs thanks to intensive use of new, advanced numerical methods. The ultimate goal is to decrease the external noise from business jet and short-medium range transport aircraft through the development of innovative low-noise installed LG and HLD components as well as new promising NRTs, thus contributing to the achievement of the Flightpath 2050 goals pursued by ACARE SRIA on aviation noise. The main Key Performance Indicator in terms of noise reduction will be to lower far-field noise generated by installed LGs and HLDs at landing/approach by respectively 2-3 and 1dB(A). Considering an equal contribution of engine and airframe to noise, we aim to reach an overall gain of about 1 dB(A) on full aircraft extrapolation in approach certification conditions. INVENTOR, gathering 16 partners (RTOs, large industries, SMEs) from 7 EU countries with a budget of €5 M will significantly contribute to Europe’s leadership in aircraft noise reduction and solutions; and increase the competitiveness of the European aviation industry.

Objectives in brief

  • Global understanding on airframe noise generation mechanisms
  • Capacity in numerical modelling / simulation of airframe noise
  • Progress in the overall airframe noise reduction via :
    • design and assessment of innovative add-on devices :
      • passive : most reliable from industrial point of view
      • active : more risky
    • direct design (via intensive CFD/CAA) of low-noise airframe components

Approach

  • Select the most promising NRTs and low-noise designs for LGs and HLDs
  • Assess them via experiments in small/middle/large scale facilities :
    • from generic airframe components to full generic aircraft model
    • including realistic aerodynamic/acoustic installation effects
  • Use/improve  up-to-date CFD/CAA techniques to simulate these configurations
  • Validate the numerical tools against the experimental databases
  • Assess results at aircraft level
  • Extrapolate results at full scale