Noise Control in Aircraft Engine Testing

Active Noise Control in an Aircraft Cabin

In propeller driven aircraft the main source for internal noise are almost tonal disturbances caused by the propeller blades that are passing the fuselage. In a certain four propeller military transport aircraft the maximum sound level in the cabin can reach up to 110 dB(A), not taking into account any noise control treatments. Inside the semi closed loadmaster working station (LMWS) the sound ...

Active Noise Control in Propeller Aircraft

A noisy environment dominated by low frequency noise can often be improved through the use of active noise control. This situation arises naturally in propeller aircraft where the propellers induce periodic low frequency noise inside the cabin. The cabin noise is typically rather high, and the passenger flight comfort could be improved considerably if this level were significantly reduced. This...

NASA Glenn ’ s Contributions to Aircraft Engine Noise Research

Aircraft Engine Noise Scattering - a Discontinuous Spectral Element Approach

The paper presents a time-domain method for computation of sound radiation from aircraft engine sources to the far-field. The effects of nonuniform flow around the aircraft and scattering of sound by fuselage and wings are accounted for in the formulation. Our approach is based on the discretization of the inviscid flow equations through a collocation form of the Discontinuous Galerkin spectral...

Requirements-Based Testing in Aircraft Control Design

To be competitive, Model-Based Design can be applied to help bring down the cost of system design and faster time to market. Model-based approaches are especially effective in the design stages and are increasingly tied in with the requirements capture and code generation and testing phases. The infrastructure for this allows linking requirements to parts of the system model as well as automati...