基于压缩驱动头的大功率扬声器结构设计与优化

发布时间：2018-01-24 12:51

  本文关键词： 大功率声波定向扬声器 压缩驱动头 相位塞 号筒 指向性　出处：《电子科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：号筒负载压缩驱动头的出现,弥补了传统电声换能器效率低且指向性差的缺点。随着相位塞和号筒理论的不断完善,基于号筒负载压缩驱动头的大功率声波定向扬声器,已成为现代定向声波武器的主要发展趋势。大功率声波定向扬声器采用高声压级与高效率的号筒负载压缩驱动头单元,利用换能器阵列原理,辐射出高指向性的声波,以实现对指定物体进行控制与攻击的目的。然而,相位塞与号筒对压缩驱动头转换效率、声场分布、波束宽度及声压级等特性的影响,国内还未有相关论文对其进行完善的理论分析。本文主要对号筒负载压缩驱动头相位塞与号筒的结构特性进行理论研究与优化设计。首先阐述了号筒负载压缩驱动头的基本原理与相位塞的结构特性,建立了号筒负载压缩驱动头的集总参数模型,并通过归一化后的模型参数,进行最大效率点分析,研究主要参数对其性能的影响。同时,根据大功率声波定向扬声器的技术指标,提出了号筒负载压缩驱动头的设计要求和相应的设计参数。然后,分析了号筒负载压缩驱动头有无相位塞时,输出声学特性的差异与存在的原因,重点介绍了带有相位塞的压缩驱动头在性能上的改进。同时,基于Smith理论,利用模态抑制法在柱坐标系下构造出的Bessel方程组对3分环形通道相位塞进行设计(主要对相位塞环形通道的位置和入口面积进行设计),并通过数值仿真分析,验证了所设计的相位塞能够有效地抑制压缩腔内的声学共振。最后,在模态分解理论的基础上,利用BEM法对60??40?号筒在模态激励下的远场辐射特性、阻抗特性和喉口处的声场分布特性进行了仿真与分析,指出号筒在远场指向性上的缺陷。并利用最小二乘法对号筒进行优化,实现了恒波束宽度号筒的设计。同时,对设计完成的号筒负载压缩驱动头进行了指向性仿真和实验测试,验证了号筒负载压缩驱动头的设计,能够满足大功率声波定向扬声器的性能要求。
[Abstract]:The emergence of the cylinder load compression drive makes up for the low efficiency and poor directivity of the traditional electro-acoustic transducer. With the development of the phase plug and the theory of the horn. A high power sonic directional loudspeaker based on the cylinder load compression drive head. High power sonic directional loudspeaker adopts high acoustic pressure level and high efficiency cartridge load compression driving head unit, and uses transducer array principle. High directivity acoustic waves are emitted to control and attack specified objects. However, the effects of phase plug and horn on the conversion efficiency, sound field distribution, beam width and sound pressure level of the compression drive head are discussed. In this paper, the theoretical research and optimization design of the phase plug and the structure characteristics of the horn load compression drive head are mainly studied and optimized. Firstly, the cylinder load compression drive is described. The basic principle of the moving head and the structural characteristics of the phase plug. The lumped parameter model of the cylinder load compression drive head is established, and through the normalized model parameters, the maximum efficiency point analysis is carried out to study the influence of the main parameters on its performance. According to the technical specifications of the high power sonic directional loudspeaker, the design requirements and corresponding design parameters of the cylinder load compression drive head are put forward. Then, the phase plug of the horn load compression drive head is analyzed. The difference of the output acoustic characteristics and the reasons for its existence are discussed. The performance improvement of the compression drive head with the phase plug is emphasized. At the same time, based on the Smith theory. The phase plug of 3-component annular channel is designed by using the Bessel equations constructed in cylindrical coordinate system (mainly the position and entrance area of the ring channel). The numerical simulation results show that the designed phase plug can effectively suppress the acoustic resonance in the compressed cavity. Finally, based on the mode decomposition theory, the BEM method is used to solve the problem. ? 40? The far-field radiation characteristics, impedance characteristics and acoustic field distribution characteristics of the horn under modal excitation are simulated and analyzed. The defects of the horn in far field directivity are pointed out, and the design of the horn with constant beam width is realized by using the least square method. The directivity simulation and experimental test of the designed horn load compression drive head are carried out to verify the design of the horn load compression drive head, which can meet the performance requirements of the high power sonic directional loudspeaker.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN643
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本文编号：1460086