【摘要】 为研究射流式调制声源的发射和传播特性,文中搭建了多种室外声场声压测试平台,提出具有普适性的大功率气流扬声器声压级量测方法,测试射流式调制声源的低频发射特性和传播特性。实验结果表明:(1)声发射方面,在不同海拔高度的对比试验发现,高海拔(4 000 m)地区声压级较低海拔(70 m)地区声压级下降4 dB;(2)声传播方面,在号筒的作用下低频声波在号筒附近呈现出一定的指向性;声压级在传播方向上呈现指数函数衰减形式。本研究对射流式调制声源的低频强声发射能力的技术边界和低频声波在大气中的传播规律给出定量描述。更多还原

【Abstract】 In order to study the emission and propagation characteristics of the fluidic air-modulated speaker,a variety of outdoor sound field and sound pressure test platforms was built and a universal sound pressure level measurement method for high-power airflow loudspeaker was proposed,and the low-frequency emission and propagation characteristics of the jet-modulated sound source was tested. The experiment result showed(1)In terms of acoustic emission,the comparative test at different altitudes found that the sound pressure level in the high altitude(4 000 m) region was 4 dB lower than that in the low altitude(70 m) region.(2)In terms of sound propagation,under the action of the drum,the low-frequency sound waves showed certain directivity near the drum. The sound pressure level attenuates exponentially in the direction of propagation. This paper describes quantitatively the technical boundary of the low-frequency strong acoustic emission capability and the propagation pattern of low-frequency sound waves in the atmosphere of the jet modulated sound source.更多还原