基于碳纳米管和聚二甲基硅氧烷的光声换能器研究

Study on photoacoustic transducers based on the carbon nanotubes and polydimethylsiloxane

为探究激光参数、光声转换层厚度对光声换能器输出声压的影响,本研究通过COMSOL仿真软件建立了光声换能器的物理模型。首先,基于聚二甲基硅氧烷(polydimethylsiloxane, PDMS)和碳纳米管(carbon nanotube, CNT)分别建立CNT、CNT-PDMS转换层模型;其次,改变激光脉冲持续时间和转换层厚度,对转换层输出声压进行测量;最后,对激光脉冲持续时间和转换层厚度所引起换能器输出声压强度的改变进行分析。结果表明,当CNT和CNT-PDMS转换层的厚度均为200μm、激光脉冲持续时间分别在10~30 ns和50 ns左右时,换能器能输出较高声压强度的超声波。仿真结果对光声换能器的研究有一定的指导意义。

In order to explore the influence of laser parameters and the photoacoustic conversion layer′s thickness on the output pressure of the photoacoustic transducer,the physical model of the photoacoustic transducer was established by COMSOL simulation software.Firstly,based on polydimethylsiloxane(PDMS)and carbon nanotube(CNT),the conversion layer models of CNT and CNT-PDMS were established,respectively.Secondly,the laser pulse duration and thickness of the conversion layer were varied to measure the output sound pressure of the conversion layer.Finally,the changes in the transducer output sound pressure intensity caused by the laser pulse duration and the thickness of the conversion layer were analyzed.The results showed that the transducer could output ultrasonic waves with higher sound pressure intensity when the thickness of both CNT and CNT-PDMS conversion layers was 200μm,and the laser pulse duration was 10~30 ns and about 50 ns,respectively.These simulation results have certain guiding significance for the research of photoacoustic transducer.