舰船声呐平台自噪声的有源结构声控制技术研究

Nowadays, the sonar detection technology has been developing towards low-frequency stage which leads to more strict requirements to the control of self-noise in sonar platform area. As a result, the tonal energy spectrums in low frequency band need to be reduced to improve the signal-to-noise ratio and ensure the ability to detect the low-frequency target. With the engineering background of self-noise control in ship's sonar platform, active structural acoustic control of cavity structures will be conducted in this study by using acoustic radiation mode theory. Firstly, the mathematical model of the active control strategy based on dominant radiation mode will be set up, the optimization method to achieve optimal configuration of the secondary forces will be proposed, the error sensing strategy in small sample size situations will be designed and optimized, and a modified algorithm for the active control strategy based on dominant radiation mode will be developed by improving current adaptive control algorithms. Then, combined simulation and sonar platform model experiment will be carried out to verify theoretical results. This study aims to realize the overall control of low frequency sound radiation in cavities and provide a new and effective technology for the self-noise control in ship's sonar platform. Related achievements of this research can also be applied to the sound radiation control of other cavity structures, which has important theoretical significances and broad application prospects.

声呐探测向低频段发展，对声呐平台区自噪声控制提出了更高的要求，需要控制其低频线谱分量以提高低频段信噪比，从而保证声呐设备对低频目标信号的探测能力。本研究将以舰船声呐平台自噪声控制为背景，利用声辐射模态开展此类腔体结构的有源结构声控制技术研究。首先，建立腔体结构中基于主导辐射模态的有源控制策略数学模型，提出优化方法实现次级作动合理布放，设计并优化少测点条件下的误差传感策略，改进现有控制算法实现基于主导辐射模态的有源控制策略。然后，通过联合仿真和声呐平台模型试验，检验理论研究成果。通过项目的研究，可以实现对腔内低频声辐射的全局控制，为舰船声呐平台自噪声控制提供新的有效的技术方法。本项目的研究成果还可以推广应用至其他腔体结构的声辐射控制场合，具有重要的理论意义和广阔的应用前景。

舰船声呐的探测距离、目标识别的精度与其声呐平台区噪声干扰的大小是密切相关的，随着声呐探测向低频段发展，控制其低频线谱分量以提高信噪比成为声呐研究的一个重要领域。.本项目主要针对声呐平台区这类腔体结构由于结构振动诱发结构噪声向腔内辐射的低频线谱控制问题，提出利用声辐射模态开展此类腔体结构的声辐射控制研究，建立了与自由空间概念一致的腔体声辐射模态理论，利用该理论只需要腔体的声模态信息，有效回避了辐射体结构模态难以获取的难题，方便腔体声辐射模态的计算。根据声辐射模态特性，制定了以主导声辐射模态贡献的声势能为目标的有源控制策略，研究了该控制策略下的控制机理。综合考虑辐射效率和模态幅度两个因素，提出了“初选-预留-后验”的主导声辐射模态确定方法。结合腔体声辐射模态特性，设计了两种少测点下声辐射模态幅度传感策略，利用正则化方法对测点位置进行了优化，非均匀分布的测点便于工程应用，均匀分布的测点便于主导声辐射模态幅度的传感。考虑次级力源位置，复强度，数量等属性对控制效果的影响，利用差分优化算法对次级力源的属性参数进行了优化，仿真结果表明，优化后的次级力源属性能获得更好的控制效果。.选取典型弹性板-矩形充水耦合腔为试验模型，以主导声辐射模态贡献的声势能为控制目标，结合主导声辐射模态确定方法，少测点下声辐射模态幅度传感等理论，开展了腔体结构声有源控制实验。实验结果验证了文中所提出的主导声辐射模态确定方法及基于主导声辐射模态的有源控制策略的有效性。