Volume 113, Issue 5, May 2003
Index of content:
- TRANSDUCTION 
113(2003); http://dx.doi.org/10.1121/1.1564019View Description Hide Description
The problem of the rigid-piston radiator mounted in an infinite baffle has been studied widely for tutorial as well as for practical reasons. The resulting theory is commonly applied to model a loudspeaker in the audio-frequency range. A special function, the Struve function occurs in the expressions for the rigid-piston radiator. This Struve function is not readily available in programs such as Matlab or Mathcad, nor in computer languages such as FORTRAN and C. Therefore a simple and effective approximation of which is valid for all z is developed. Some examples of the application of the Struve function in acoustics are presented.
113(2003); http://dx.doi.org/10.1121/1.1562648View Description Hide Description
One of the most powerful and clear methods for solving electromechanical transducer problems is the energy method based on the use of the Euler–Lagrange equations. The general expression is developed in a form convenient for applying the energy method to the calculation of the internal energy of a piezoelectric body under nonuniform deformation. The electrical and mechanical variables in this expression are separable under certain conditions and the underlying physics is illustrated with particular examples of bars made of piezoelectricceramic for the case of transverse and axial polarization. In the case that the electrical and mechanical variables are not separable, the contribution of the mutual energy term to the total internal energy is expressed analytically.