Ri 1[m] Inner sphere radius
Rext 10[m] Exterior field evaluation distance
f0 1000[Hz] Driving frequency
c0 1500[m/s] Speed of sound
lambda_min c0/f0 Wavelength
A 0.5[m] x-semiaxis ellipsoid
B 0.25[m] y-semiaxis ellipsoid
C 0.25[m] z-semiaxis ellipsoid