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Active noise control method based on generalized Lorentz system

An active control and noise technology, applied in the direction of sound-generating devices, instruments, etc., can solve the problems of immaturity and poor suppression effect

Inactive Publication Date: 2017-07-21
HARBIN UNIV OF SCI & TECH
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  • Abstract
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Problems solved by technology

[0003] However, the current acoustic energy suppression technology for ship radiated noise signals is still immature, and the suppression effect of existing technologies is poor

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  • Active noise control method based on generalized Lorentz system
  • Active noise control method based on generalized Lorentz system
  • Active noise control method based on generalized Lorentz system

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Embodiment Construction

[0040] Exemplary embodiments of the present invention will be described below with reference to the accompanying drawings. In the interest of clarity and conciseness, not all features of an actual implementation are described in this specification. It should be understood, however, that in developing any such practical embodiment, many implementation-specific decisions must be made in order to achieve the developer's specific goals, such as meeting those constraints related to the system and business, and those Restrictions may vary from implementation to implementation. Moreover, it should also be understood that development work, while potentially complex and time-consuming, would at least be a routine undertaking for those skilled in the art having the benefit of this disclosure.

[0041] Here, it should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only the device structure and / or processing steps closely related to the ...

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Abstract

The invention provides an active noise control method based on a generalized Lorentz system. In order to solve a problem of suppressing acoustic energy of radiation noises of a ship, the method employs a classical Lorentz system and adds a time-lag feedback controlled quantity and an external excitation unit based on the system; and a noise control effect is realized by using a chaotic dynamics determination method. For a transformed generalized Lorentz system, the output dynamic characteristics, including a phase trajectory chart, a bifurcation diagram and a Lyapunov exponent diagram, are observed by using Matlab programming; an external excitation amplitude parameter, a frequency parameter, and a corresponding parameter range in a cyclic motion, quasi-cyclic motion, or chaotic motion state of a system output are given; and noise source energy values and energy changing values at fixed frequencies before and after active sound source application are provided by using a spectrum curve and thus noise suppression effects under different sound source effects are represented.

Description

technical field [0001] The invention relates to noise processing technology, in particular to an active noise control method based on a generalized Lorentzian system. Background technique [0002] Ship acoustic stealth has always been the most concerned issue in the maritime military field. Ship radiation noise is the main observation method for the enemy to detect targets. The noise mainly comes from mechanical noise, propulsion system noise and hydrodynamic noise. Ship radiated noise is mainly low-frequency noise, and low-frequency noise has a long wavelength. At first, passive control methods such as floating rafts, flexible hoses, mufflers, pump jet propulsion, electric propulsion, air curtain noise reduction, and anechoic tiles were used to reduce vibration and reduce noise. For low-frequency noise, passive noise control has obvious shortcomings. The proposal of active noise control method in the 1930s solved this problem. A large number of studies have begun to apply ...

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): G10K11/16
CPCG10K11/16
Inventor 兰朝凤隋雪梅吕收韩闯康守强郭小霞罗大钧海淞皓
Owner HARBIN UNIV OF SCI & TECH
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