对于组合式纵振压电水声换能器,当采取增加它的辐射面积、减小辐射盖板的厚度和降低机械Q值等方法来提高它的辐射功率并展宽其工作频带时,实验观测到换能器的辐射面不再作纯等幅纵振动,而耦合有弯曲振动。因此存在节线区域,它们一般呈圆线状,称为辐射面的波节线。通过Al_2O_3粉末法可以测量这些波节线的分布及大小。 For the combined longitudinal vibration piezoelectric hydroacoustic transducer, when its radiation area is increased, the thickness of the radiation cover is reduced and the mechanical Q value is reduced to increase its radiation power and broaden its working frequency band, experimental observations The radiating plane to the transducer no longer makes longitudinal oscillations of pure amplitude, coupled with bending vibrations. Therefore, there are nodal areas, which are generally round, called radiating nodal lines. The distribution and size of these nodal lines can be measured by Al 2 O 3 powder method.