Research progress of helicopter noise suppression technology based on materials/structures

Abstract

Helicopter has achieved rapid development and wide application in various fields, due to its unique flight mode. However, the noise is also a particular feature of the helicopter, which people cannot bear without protection. With the requirements of helicopter comfort and low noise pollution, its noise has become an urgent problem that must be solved. According to the main sources and propagation ways of external noise and internal noise of the helicopter, the current situation of material and structure-based helicopter noise control in domestic and international scope was reviewed. The noise control characteristics and effects of conventional sound absorbing materials, intelligent piezoelectric control materials, acoustic super material/structure and damping material were introduced in this paper. Traditional materials are no longer suitable for the current lightweight requirements of the helicopter. Intelligent composite materials, new sound-absorbing structures, and acoustic super material/structure have become potential selections of noise suppression. Finally, combined with the current development status of helicopter vibration and noise reduction materials, the development trend of helicopter noise reduction material/structure in the future such as active noise reduction technology, resonance sound absorption, metamaterial acoustic band gap, damping material noise reduction and so on, is proposed, and feasible research ideas for the development direction of helicopter noise suppression materials/structures are put forward.

Keywords

• helicopter
• noise suppression
• material
• structure
• development status and trend