초록 ▼

The present invention is an active-control system for attenuating noise in a duct having a fluid flow. An array of stators having a longitudinal length is positioned axially within the duct. A first array of sound sources capable of generating spinning mode sound and is positioned a distance upstrea

The present invention is an active-control system for attenuating noise in a duct having a fluid flow. An array of stators having a longitudinal length is positioned axially within the duct. A first array of sound sources capable of generating spinning mode sound and is positioned a distance upstream of a first plane defined by the upstream-most portion of the stators, relative to the fluid flow. The upstream distance is less than the longitudinal length of the stators. A second array of sound sources capable of generating spinning mode sound and is positioned a distance downstream of a second plane defined by the downstream-most portion of the stators, relative to the fluid flow. The downstream distance is less than the longitudinal length of the stators. A controller causes the first and second arrays of sound sources to generate sound including spinning mode sound such that it cancels a portion of the noise within the fluid flow that passes through the stators.

대표청구항 ▼

[What is claimed is:] [1.]an array of stators positioned axially within the duct having a longitudinal length;a first array of sound sources capable of generating spinning mode sound and positioned a distance upstream of a first plane defined by the upstream-most portion of the stators, relative to

[What is claimed is:] [1.]an array of stators positioned axially within the duct having a longitudinal length;a first array of sound sources capable of generating spinning mode sound and positioned a distance upstream of a first plane defined by the upstream-most portion of the stators, relative to the fluid flow, the upstream distance being less than the longitudinal length of the stators;a second array of sound sources capable of generating spinning mode sound and positioned a distance downstream of a second plane defined by the downstream-most portion of the stators, relative to the fluid flow, the downstream distance being less than the longitudinal length of the stators; anda controller for causing the first and second arrays of sound sources to generate sound including spinning mode sound such that it cancels a portion of the noise within the fluid flow that passes through the stators.