Sound-Hard/Soft Sphere
The acoustic counterparts of the PEC sphere have radius $r$ and are assumed to be located in the origin. On a sound-hard surface the normal velocity, and hence the normal derivative of the total pressure, vanishes; on a sound-soft (pressure release) surface the total pressure vanishes.
API
SphericalScattering.HardSphere — Type
HardSphere(
radius = error("missing argument `radius`")
)Constructor for a sound-hard sphere, that is, for a Sphere with the boundary condition SoundHard.
HardSphere is an alias of Sphere{SoundHard}, so that it can be dispatched on as well.
SphericalScattering.SoftSphere — Type
SoftSphere(
radius = error("missing argument `radius`")
)Constructor for a sound-soft sphere, that is, for a Sphere with the boundary condition SoundSoft.
SoftSphere is an alias of Sphere{SoundSoft}, so that it can be dispatched on as well.
Both are aliases: a sound-hard sphere is a Sphere{SoundHard}, that is, a sphere carrying the boundary condition SoundHard as its type parameter. Every scatterer is a Scatterer parametrized by the condition on its surface, which allows to address, e.g., all acoustic scatterers at once as Scatterer{<:AcousticBoundary}.
These two are the only acoustic scatterers with a closed surface of revolution for which the cheap spherical series applies. The spheroids and the disc are documented separately, together with the accuracy of their solution, under Spheroid and Disc.