Passive Techniques for Fan Noise Reduction in New Turbofan Engines: Review

Abstract

Among the various environmental concerns, the aircraft noise item has been constantly growing in importance over the past years. Measures for its reduction at the source as well its mitigation around airports must take into account aspects of medicine and technical design as well as legal and land use planning aspects. Fan noise is one of the principal noise sources in turbofan aero-engines. In this paper a review of the main technologies employed for the reduction of fan noise turbofan engines is presented.

Low-frequency interior noise in prop-driven aircrafts: Sources and control methodologies

“…Aircraft noise emissions reduction has become a driving factor for competitive aircraft design, as political and environmental laws have become more firm. [1][2][3][4] Noise reduction techniques can be broadly classified as passive and active methods. Passive control involves reducing the radiated noise by energy absorption, while the active method involves reducing source strength or modifying acoustic field in the duct to obtain noise reduction.…”

Supersonic Jet Noise: Main Sources and Reduction Methodologies

“…Aircraft noise emissions reduction has become a driving factor for competitive aircraft design, as political and environmental laws have become more firm [1][2][3]. Additionally, takeoff noise reduction is a key challenge for developing future supersonic jetliners.…”

Noise Reduction in Buildings Using Sound Absorbing Materials

“…Too much noise obviously impairs our physical and mental existence and therefore it is reasonable to pursue Technology Assessment concerning noisy technologies [1][2][3][4]. In other words, noise has turned into one of the most important among the environmental factors on which industry sets down a big part of its efforts and concerns.…”