Acoustic simulations to reduce cockpit noise
The reduced weight of carbon fibre-reinforced polymers (CFRPs) curbs fuel consumption. The use of CFRP materials in fuselage structures helps to achieve a more comfortable cabin pressure thanks to greater strength and higher acceptable cabin humidity since composites are not subject to corrosion. The added strength of composites also allows for bigger windows, resulting in improved visibility for crew and passengers. A CFRP fuselage offers many benefits over traditional metallic materials. However, it has not been applied to medium or large passenger aeroplanes in Europe. Another key consideration is the effect the CFRP structure has on a cockpit's acoustic environment. The EU-funded DYNAPIT (Nose fuselage/cockpit dynamic characterization for internal noise attenuation) project used various software to simulate the acoustic performance of a CFRP nose fuselage design. It also conducted a comparative analysis of a conventional metallic design. The physical properties of CFRP structural components give a different vibroacoustic response compared to metallic structures. CFRP technologies can cause higher noise levels in the cockpit. Project partners applied numerical methods to accurately assess the structural dynamics and resulting internal acoustics of a new nose fuselage and cockpit design entirely by computational analysis. Only recently has the accuracy of vibroacoustic analysis techniques become suitable enough to support design. The DYNAPIT team modelled an aircraft's internal acoustic setting as part of the design process. Applying these techniques to such aircraft acoustic assessments are uncommon in aerospace engineering. DYNAPIT's acoustic noise evaluation should contribute to improving the fuselage nose and cockpit design in an effort to achieve superior acoustic performance.
Keywords
Cockpit noise, carbon fibre-reinforced polymers, DYNAPIT, nose fuselage, acoustic performance
