Device to Reduce Cavity Noise in Aircrafts Using Active and Passive Flow Control

Technology #14967

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Subrata Roy
Arnob Das Gupta
Managed By
Lenny Terry
Assistant Director 352-392-8929
Patent Protection
US Patent 9,746,010

Facilitates Noise Control and Prevents Fatigue Damages from Open Cavity Flows

This noise reduction device, with active and passive receptive channels, protects aircraft from damage by decreasing the noise generated from shear layers of flow over open cavities. These pressure oscillations can cause fatigue damage to aircrafts’ landing gears and weapons bays. Researchers at the University of Florida have developed a device that responds to flow pressure actively (using plasma) and passively through a geometric modification of the system (via grooves that reduce pressure and noise). The traditional noise reduction solution, a spoiler, requires additional power, a mass injection system and adds viscous drag. The benefit of this noise reduction device, which modifies flow passage, is that it requires no additional flow restrictions or systems. This technology will prove valuable to companies that work with large aircraft supply chains.


Device that actively and passively reduces acoustic pressure oscillations generated from open cavity flow to make landing gears and weapons bays less susceptible to damage


  • Actively and passively responds to flow pressure, significantly lowering noise levels from >140dB to a more tolerable level
  • Doesn’t add viscous drag and requires no additional power or flow restrictions, creating a cost effective alternative to traditional noise reduction solutions
  • Reduces fatigue damages to landing gear and weapons bay, increasing the lifespans of these aircraft components


Using plasma and specific geometric modifications (i.e. grooves), University of Florida researchers have significantly decreased the shear layer impingement that causes excessive noise and pressure in aircraft and results in damage to landing gears and weapons bays. By introducing a channel at the trailing edge of the cavity at a location determined by pressure distribution, the researchers effectively suppressed detrimental acoustic tones.