Research On Non-linear Control Method Of Line-spectrum Vibration Characteristics Using Intelligent Base Of Ship

With the development of ship noise suppressing technology and the promotion of detection capability of various acoustic detection equipment,the control of ship line-spectrum noise,especially the low-frequency line-spectrum noise,has become the important limiting factor for the improvement of ship acoustic stealth performance.A non-linear control method for line-spectrum vibration characteristics using intelligent base structure is proposed in this article.The chaotic vibration is excited by the non-linear characteristics of intelligent base structure,thus the low-frequency line-spectrum vibration input can be expanded to a wide-band output.From the perspective of controlling low-frequency line-spectrum vibration,the low-frequency line-spectrum noise with ship type and operation status information is suppressed.Firstly,in order to improve the lack of effective control methods for low-frequency line-spectrum vibration of ships,a non-linear control method of line-spectrum vibration characteristics is proposed,which can realize the reconstruction of low-frequency line-spectrum.A mechanical model of ship intelligent base structure is established,which uses Bouc-Wen model to describe the non-linear constitutive characteristics of MR damper.The dynamic characteristics of the mechanical model and the feasibility of causing chaos in the mechanical model are analyzed by numerical calculation.Based on the typical base structure of ship,a ship intelligent base structure for non-linear control method of line-spectrum vibration characteristics is designed by using MR damper.Secondly,for the feasibility of non-linear control of low-frequency line-spectrum vibration characteristics using ship intelligent base,it is proved that the intelligent base structure with MR damper can inspire chaotic vibration in low-frequency range by numerical analysis.The finite element model of intelligent base structure is established,and the vibration response and impedance characteristics of ship intelligent base structure under low-frequency line-spectrum excitation are calculated.The line-spectrum reconstruction and vibration suppression of ship intelligent base structure are proved.Finally,in order to verify the effectiveness of the non-linear control method based on the linear spectrum vibration characteristics of the ship intelligent base,the experimental platform of the ship base is built and the scaled model experiment is carried out.The influence of input current and excitation frequency on the line-spectrum reconstruction of ship intelligent base is analyzed.Compared with typical base,the effectiveness of the non-linear control method for low-frequency line-spectrum vibration characteristics of intelligent base is verified from two aspects of line-spectrum reconstruction and vibration suppression.This method has a great application prospect in submarines and other acoustic invisibility warships,and can effectively control low-frequency line-spectrum noise of all types of warships from the perspective of controlling low-frequency line-spectrum vibration characteristics.