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匹配层换能器在实用中往往由于辐射阻抗的变化破坏了“最佳”匹配层参量的选取。本文从反映阻抗概念给出了必要的匹配层厚度修正,并以实例计算证明了修正公式的实用意义。  相似文献   
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唐义政  吴昭军  汤立国 《中国物理 B》2010,19(5):54303-054303
A spherical cap radiator is one of the important parts of an underwater wide-beam imaging system.The back radiation of a traditional spherical cap radiator,which is composed of a vibrating cap and a rigid baffle,is strong and its far-field directivity function may fluctuate in big amplitude in the vicinity of the polar axis.These shortcomings complicate the processing of the reflective waves received for imaging the targets.In this study,the back radiation is weakened by adding an acoustic soft material belt between the vibrating cap and the rigid baffle.And the fluctuation mentioned above is lowered remarkably by dividing the spherical cap radiator into many annuluses and a relatively smaller spherical cap,and by controlling the phase retardations of all elements appropriately.Furthermore,the numerical experiments are carried out by the finite element method(FEM) to prove the validity of the above methods.  相似文献   
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换能器辐射阻抗变化对匹配层参数的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
匹配层换能器在实用中往往由于辐射阻抗的变化破坏了“最佳”匹配层参量的选取[1]。本文从反映阻抗概念给出了必要的匹配层厚度修正[2],并以实例计算证明了修正公式的实用意义。  相似文献   
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