The class I flextensional underwater transducer with the barrel-stave structure has been analyzed thoroughly by the way of combining the finite element method(FEM) and the boundary element method(BEM).Its essential idea has been obtained from the data sharing of the mesh models and the solving results,and so the complementary advantages between the structure or vibration analysis of FEM and the acoustic field analysis of BEM have been achieved.The corresponding tests showed that the combined analysis method...