Content Inside:
The design methodology uses a combination of high and low fidelity tools to assess the performance and acoustics of the aircraft. The goal set by the Silent** Aircraft Initiative is a viable, commercial aircraft design with noise levels imperceptible outside the airport perimeter in a well-populated urban environment. To be viable, the aircraft requires a fuel burn comparable to modern conventional aircraft. The detailed airframe design incorporates leading edge camber of the centerbody to provide pitch trim without penalties in induced drag, wave drag, and trim drag. A low noise approach is achieved with reduced approach velocity and increased distance between the airframe and the observer. This slow and steep approach profile is enabled through a combination of thrust vectoring, quiet drag generation, and leading edge high-lift devices. Figure 1. Three-dimensional view of the current Silent Aircraft eXperimental airframe design. The aircraft is designed to carry 215 passengers in a three-class configuration a distance of 5,000 nm. This paper presents the detailed three-dimensional aerodynamic and aeroacoustic design of this aircraft. During approach, airframe noise is dominant with source contributions from the undercarriage, the high-lift devices, the control surfaces, drag augmentation, and the scattering of boundary layer turbulence at the trailing edges commonly referred to as airfoil self-noise. The sound pressure level from these noise sources have an intensity proportional to 1/r2 and un where n is 5 for trailing edge scattering and 6 for dipole type sources such as the undercarriage. The scaling law thus suggests that the noise at the observer location can be reduced by using steep and slow approach profiles. The aerodynamic design required for such a quiet landing is the focus of this paper.
source:http://silentaircraft.org/ found via google search
Tags : airframe noise, airframe design, silent aircraft initiative, thrust vectoring, low fidelity, design methodology, google, source contributions, control surfaces, self noise, conventional aircraft, observer location, class configuration, dimensional view, aerodynamic design
If you see unrelated pdf files with the description or copyrighted material published, please report to us, we'll correct/delete it it as soon as possible.NONE OF THOSE MATERIALS ARE HOSTED IN THIS SERVER NOR UPLOADED BY ME IN SOMEONE'S SERVERS. Read our DISCLAIMER for more detail.
We are neither affiliated with authors and brands nor responsible for its content and change of content.
Information contained herein is provided "as is" without warranty of any kind, either expressed or implied, including any warranty of merchantability or fitness for a particular purpose. In no event shall ANYONE be held liable for any loss of profit, special, incidental, consequential, or other similar claims.