Noise Source Identification

Noise Source Identification (NSI)

Noise Source Identification (NSI) is an essential tool to reduce noise, and to understand and optimize noise that cannot be eliminated. With Brüel & Kjær noise source identification equipment, acousticians can diagnose, visualize, understand and solve noise issues. By tracing noise back to very specific components, engineers can target their mitigation efforts more accurately.

Moving source beamforming

Identification, mitigation and optimization

After locating noise sources, acoustical hotspots and leaks using a variety of tools ranging from hydrophones to outdoor arrays of up to 144 channels, it is possible to identify and characterize the most important sub-sources.

Ranking these helps decide where mitigation strategies can most effectively reduce overall sound power radiation, or reduce certain noise components such as specific frequency content. Mitigating noise can be accomplished by reducing, damping, or decoupling noise sources from the overall structure.

Through the iterative use of NSI tools in the design and prototype phases of product development, the overall noise profile of the product can be optimized, thus ensuring proper compliance with given noise limits and regulations.

Colour-coded noise maps

Different stages of noise-source identification call for different capabilities. Early 'snapshot' measurements such as in aircraft cabins, demand equipment that is easy to deploy in order to obtain results as quickly as possible.

Our software displays sound values as colour-contours in high-resolution noise maps that are easy to interpret.

For fine, close-up detail such as on a hearing aid, acoustic holography delivers similar results in high resolution, while for noise source location on larger objects such as vehicles in a wind tunnel, or from a distance, beamforming can quickly identify noise contributions.

When dealing with moving objects, such as wind turbines and flying aircraft, this can be acoustically mapped using moving-source beamforming.