A0-3F

Benchmark Problems

Benchmark Problem A0-3F

-Properties-

category	type	index	domain	object	note
A. exterior	0. basic	A0-3F	frequency	sphere with a point source	scattering

Geometry:
Spherical surface (1 m in diameter) in the free field.

Boundary condition:
The surface is rigid boundary. A piston source (S) is located at (0, 0, 3), assuming its stationary vibration with acceleration amplitude 1.0 m/s².

Fig. A0-3F-1: Geometry of problem A0-3F (unit: m).

-Task A-

Directivity:
Sound pressure amplitude [Pa] of a scattered field at 181 points (R1), 2 m away from the sphere's center on the plane x = 0, located at 1 deg intervals (theta = 0, ..., 180 deg). At the octave-band mid-frequencies (f = 31.5, 63, 125, 250, 500, 1k, 2k, 4k Hz).

Dataform:
d-a0-3fa.xls

-Task B-

Frequency response:
Sound pressure amplitude [Pa] of a total field (the sum of an incident field and a scattered field) at 3 points (0, 0, 1) (R2), (0, 1, 0) (R3) and (0, 0, 10) (R4). At the frequencies with 1 Hz intervals from 20 Hz to 4 kHz; or with 50 Hz intervals from 50 Hz to 4 kHz.

Dataform:
d-a0-3fb.xls