考虑声固耦合的管道噪声控制技术研究

发布时间：2018-05-27 17:44

本文选题：管道噪声 + 消声器　；参考：《哈尔滨工程大学》2016年博士论文

【摘要】：管道噪声是环境噪声中的一个重要组成部分,不可避免地对我们的生活和工作产生消极的影响。当前,管道噪声的控制措施可以分为主动和被动两类。主动控制系统的复杂性等因素限制了其广泛应用,相对而言,被动控制技术的使用更加成熟。在被动控制技术中,吸声材料能够有效地消除中、高频噪声,而使用基于截面突变和空腔共振的抗式结构是阻断低频噪声传播的最有效手段。然而,对于传统的抗式结构,一方面管道横截面突变会增大阻力损失,另一方面,低频降噪量、降噪带宽和消声器体积三个指标的相互制约,有时会限制或影响它的使用。有别于传统的依赖截面突变的抗式结构,Huang等人将张紧的膜或弹性板结构引入到管道噪声控制中,利用柔性结构与管内声波的耦合作为另外一种以阻抗失配达到消声目的的实施形式,进而发展出了多种低频、宽带、紧凑的膜结构消声器和弹性板消声器。本文在Huang等人的研究基础上,建立了多种构型的膜结构消声器的解析计算方法。使用Green's函数和Kirchhoff-Helmholtz积分来计算矩形和圆形截面管道内部膜片的辐射声场和膜结构消声器的传递损失。将单腔室膜结构消声器的二维数学模型推广到双腔并联和双腔串联膜结构消声器,对膜片的质量和张紧力进行了优化,探索了膜片位置变化、多膜片参数配合等因素对消声器声学性能的影响。研究表明,由于解析方法中使用了满足刚性壁面边界的特征函数,因此计算过程中耦合面附近的横向质点振速振荡较大,导致收敛速度缓慢。鉴于此,本文利用切比雪夫配点法,结合区域分解技术,建立了与解析计算模型一一对应的高精度数值模型和计算方法,不仅克服了解析方法在耦合面上收敛速度慢的缺点,而且实现了针对膜结构消声器的解析—数值方法的相互验证。其次,通过将梁的振动位移表示为Fourier级数和辅助多项式的形式,本文将当前用于简支或固支边界的弹性板消声器的声学计算模型拓展到了多种边界的情况,实现了利用一个数学模型覆盖多种边界的目的。利用该通用模型,对比分析了多种经典边界下弹性板消声器的传递损失,研究了弹性板边界刚度弱化对消声器传递损失的影响。另外,受一种人工耳蜗模拟装置的启发,本文提出了一种基于局域响应模型(LRM)的管道噪声控制方法,结合集总参数法和Fourier-Galerkin方法,分析了基于这种方法的管道消声器的声学性能。研究表明:在不考虑腔室的影响时,入射声波传播到相应的共振梁或者膜附近时波速可以在很短的距离内大幅降低,随之带来显著的声反射;LRM具有宽频降噪的特点,与单管道膜结构或弹性板消声器的特征相似,但其传递损失峰的频率和幅值更容易调节。带有腔室的情况下,由于腔室内的介质对LRM产生了较强的等效质量负载效应,会削弱LRM的响应,影响LRM消声器的声学性能。可以选用低密度的气体以减少来自腔室的质量抗,提高LRM的响应,改善LRM消声器的声学性能。文中还研究了结构质量、刚度和阻尼等参数对LRM消声器传递损失的影响。最后,本文设计了实验方案和实验台架,对LRM消声器进行了实验研究。利用声波分解法测量了不同张紧力下膜片的阻抗,利用四传声器-双负载方法测量得到了膨胀腔和LRM消声器的传递损失,分析了 LRM消声器的声学性能,完成了与解析计算结果的对比验证。
[Abstract]:Pipeline noise is an important part of environmental noise, which inevitably has a negative impact on our life and work. At present, the control measures of pipeline noise can be divided into two types: active and passive. The complexity of the active control system restricts its wide use. In contrast, the use of passive control technology is more used. In passive control, sound absorbing materials can effectively eliminate medium and high frequency noise in passive control technology, and the most effective means to block low frequency noise propagation is to use an anti type structure based on cross section mutation and cavity resonance. However, for the traditional anti type structure, on the one hand, the mutation of the pipe cross section will increase the resistance loss, on the other hand, low frequency drop. The mutual restriction of three indexes, noise, noise reduction bandwidth and muffler volume, sometimes restricts or affects its use. It is different from the traditional resistant structure dependent on cross section mutation. Huang et al. Introduce the tensioned membrane or elastic plate structure into the pipe noise control, and use the coupling of the flexible structure and the acoustic wave in the tube as the other type of impedance. A variety of low frequency, broadband, compact membrane structure muffler and elastic plate muffler are developed. Based on the research of Huang et al. In this paper, the analytical calculation method of multi configuration film structure muffler is established. Using the Green's function and the Kirchhoff-Helmholtz integral to calculate the rectangle and the circle. The radiation field of the inner diaphragm and the transmission loss of the membrane structure muffler. The two-dimensional mathematical model of the single chamber membrane structure muffler is extended to the double cavity parallel and double chamber series membrane structure muffler. The quality and tension of the diaphragm are optimized, and the change of the diaphragm position and the parameters matching of the multi diaphragm are used to eliminate the noise. The study shows that the characteristic function of the rigid wall boundary is used in the analytical method, so the vibration velocity of the transverse particle near the coupling surface is larger and the convergence speed is slow in the calculation process. In view of this, the paper uses the Chebyshev matching point method and the region decomposition technique to establish the analytical calculation model. The high precision numerical model and calculation method not only overcome the shortcoming of the slow convergence speed of the analytical method on the coupling surface, but also realize the mutual verification of the analytical numerical method for the membrane structure muffler. Secondly, by expressing the vibration displacement of the beam to the form of Fourier series and auxiliary polynomial, this paper will be used in this paper. The acoustic calculation model of the elastic plate muffler used for the simple supported or fixed boundary is extended to a variety of boundary conditions, and the purpose of covering a variety of boundary with a mathematical model is realized. By using the general model, the transmission loss of the elastic plate muffler under a variety of classical boundary is compared and analyzed, and the weakening of the stiffness of the elastic plate boundary stiffness is studied. The influence of muffler transmission loss. In addition, inspired by a cochlear simulation device, a pipeline noise control method based on local response model (LRM) is proposed. Combined with lumped parameter method and Fourier-Galerkin method, the acoustic performance of the pipe muffler based on this method is analyzed. The study shows that the cavity is not considered. When the incident wave propagates to the corresponding resonant beam or membrane, the wave velocity can be greatly reduced in a very short distance and brings significant acoustic reflection. LRM has the characteristics of wide-band noise reduction, similar to the characteristics of single tube membrane structure or elastic plate muffler, but the frequency and amplitude of the transmission loss peak are more easily adjusted. In the case of the chamber, because the medium in the chamber produces a strong equivalent mass load effect on the LRM, it will weaken the response of the LRM and affect the acoustic performance of the LRM muffler. The low density gas can be used to reduce the quality resistance from the chamber, improve the response of the LRM and improve the acoustic performance of the LRM sound elimination device. The influence of degree and damping on the transmission loss of the LRM muffler. Finally, the experiment scheme and the experimental platform are designed. The experimental study of the LRM muffler is carried out. The impedance of the diaphragm under different tension forces is measured by the acoustic wave decomposition method. The transmission loss of the expansion cavity and the LRM muffler is measured by the four microphone double load method. The acoustic performance of LRM muffler is analyzed, and the comparison with the analytical results is completed.
【学位授予单位】：哈尔滨工程大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：U173;TB535

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