Skip to main content
. Author manuscript; available in PMC: 2008 Apr 12.
Published in final edited form as: J Acoust Soc Am. 2004 May;115(5 Pt 1):1942–1954. doi: 10.1121/1.1687835

FIG. 1.

FIG. 1

Definition of coordinate axes for acoustic field calculations. The origin (O) of the coordinate system is defined as the intersection between the z and r axes in a cylindrical coordinate system. The z axis is coincident with the piston normal, and individual field coordinates are indicated by the pair (r0,z0). The radius of the circular piston is designated by a, the extent of the field calculation in the radial direction is 1.5a, and the extent of the computed field in the axial direction is a2/λ. These are the same coordinates used by Zemanek (Ref. 8) and Lockwood and Willette (Ref. 3) for calculations of pressure fields generated by circular pistons.