Statistical nearfield acoustic holography method for conical surface sound source

Abstract

The invention discloses a statistical nearfield acoustic holography method for a conical surface sound source. A measurement surface conformal with shell structure equipment is used for obtaining holography sound pressure data. On the basis of a statistical optimal cylindrical surface nearfield acoustic holography theory method, through cylindrical surface-conical surface coordinate transformation, a conical shell structure equipment radiation sound field is calculated directly through compound sound pressure on a spatial domain holography surface, the application blank of the nearfield acoustic holography technology in the conical surface sound source is filled up, the effectiveness of the nearfield acoustic holography technology in low-frequency noise analysis is displayed, the nearfieldacoustic holography technology is suitable for an underwater ordnance of a tapered shell structure so as to provide a theoretical basis for the acoustical stealth performance evaluation of the equipment of the tapered shell structure, and therefore, the nearfield acoustic holography method has important theoretical significance and an engineering application value. The statistical nearfield acoustic holography method is suitable for the radiation sound field reconstruction of the equipment of the tapered shell structure mainly under low-frequency vibration noise, the radiation sound field ofthe equipment of the tapered shell structure is visually displayed so as to visually see the size and the distribution situation of the radiation sound field.

Description

technical field [0001] The invention belongs to the field of acoustic radiation signal processing of mechanical structures, in particular to a method for statistical near-field acoustic holography of cone sound sources. Background technique [0002] As naval combat equipment, underwater vehicles have large endurance, strong maneuverability, and strong independent combat capabilities, but the noise waves generated by them can be transmitted to hundreds of nautical miles in seawater, and are easily detected by local areas, which seriously weakens their acoustic stealth performance. , reducing its combat performance. Therefore, improving its acoustic stealth performance is the key to ensuring its security and combat capability. At present, the primary technical problem to be solved is to obtain the radiated sound field of the underwater vehicle, so as to realize the accurate evaluation of its stealth performance. However, it is difficult to accurately evaluate the acoustic st...

AI Technical Summary

Problems solved by technology

However, the traditional NAH uses the spatial two-dimensional Fourier transform to realize the deconvolution operation to obtain the reconstructed surface sound pressure, which will bring window effects and winding errors during the holographic calculation process, so the area of ​​the test aperture is required to be at least twice the area of ​​the sound source. Accurate testing to meet NAH requirements is difficult to achieve for large-scale conical shell structures

In addition, when the underwater vehicle sails at low speed, the vibration noise of mechanical equipment is the main noise, and its sound source is located in the cone structure. However, in the current NAH research, there has been no research on the reconstruction of the radiation sound field of the cone sound source.

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