封闭水池中非自由场重建的实验方法

Experimental Research of Sound Field Reconstruction Method for Non-free Sound Field of Sealed Tanks

为实现水下封闭空间中非自由声场的重建,提出一种单全息面的声波分离方法。用声场中不同位置声压的球谐函数展开描述非自由声场,并在声场重建过程中剔除环境噪声,达到目标声源的直达声与环境噪声分离的目的。在六面反射的封闭水槽内,进行非自由声场重建的实验,获得了目标声源的直达声,并与消声水池中的测量结果进行对比,表明:基于单全息声压测量面的声波分离方法可以有效重建水下非自由声场,声波分离后目标声源辐射声场的重建误差小于30%。

In order to reconstruct the non- free acoustic field in an underwater sealed cavity, a new sound waveseparation method based on single holographic plane is proposed. Spherical harmonic series expansion for sound pressure ofdifferent space positions is used to describe the target source and environment noise. By getting rid of the wave radiationfrom noise sources during sound field reconstruction procedure, the standing wave from the target source and the travelingwave from noise sources can be separated. The non- free sound field in the sealed tank with six reflection flats isreconstructed, and the standing wave from the target source can be obtained. The calculation results are compared with themeasurement results in an anechoic pool. It can be found that the sound wave separation method based on single holographymeasurement plane can effectively reconstruct the underwater non-free sound field, the reconstruction error for the soundfield produced by the radiation target sound source is less than 30 %.