The DJINN project is one partner to the 3-project cluster:

Advancements in aerodynamics, aeroacoustics and
innovative propulsion systems for quieter and greener aircraft

The project partners belonging to the three projects

DJINN,

INVENTOR and

ENODISE

are strongly linked – represented by the three boxes of this figure, with a black frame for DJINN, a yellow frame for INVENTOR and a pink frame for ENODISE.

Figure: courtesy: E. Manoha, ONERA

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.

ENODISE  is a low-to-mid-TRL enabler project, meant to develop the knowledge, data, tools and methods that are necessary to understand, model and optimize engine-airframe aerodynamic and acoustic installation effects. The focus is on the following innovative  architectures bringing a tighter integration of the propulsive system with the wing, fuselage or control surfaces:

  • partly buried engines, where boundary layer ingestion affects the aerodynamic and acoustic performance;
  • distributed propulsion systems mounted on fixed or tilted pylons, in puller/pusher configurations on a fixed wing airframe or on a control surface to achieve vectorial thrust;
  • multi-copter configurations with co- or contra-rotating tandem rotors.