复频聚焦超声换能器声场研究

Study on acoustic field by a bi-frequency ultrasonic focused transducer

研制了一种能实现两种频率超声叠加的自聚焦型超声换能器 ,利用瑞利公式对其声场进行了计算 ,确定了焦区位置 ,计算结果与测量值符合较好 .对复频叠加声场的频谱进行了测量 ,发现其有两个原波、和频波、差频波、倍频波等成分 .理论分析及实验结果表明 。

A new kind of bi frequency ultrasonic focused transducer is designed, and the distribution of its acoustic field is theoretically studied. Its focal area is determinated and it is well in agreement with experimental results. Also the spectrum of the focal acoustic field radiated by the transducer in water is studied. Not only the two original waves but the sum frequency, difference frequency and multiple frequency waves have been detected, which prove the occurrence of scattering of sound by sound.