An off-center fluid inclusion

A displaced, rotated dense inclusion breaks the symmetry of an ellipsoidal host. Both interfaces show total pressure, with the host translucent so the inclusion is visible through it. The gold arrow marks the incident wave direction.

using AcousticScattering
using CairoMakie: plot, save

surfaces = [
    mesh(; semiaxes=(0.034, 0.026, 0.022), resolution=0.5, qorder=4),
    mesh(; semiaxes=(0.013, 0.008, 0.010), center=(0.009, 0.004, 0.002),
        rotation=(axis=(0, 0, 1), angle=deg2rad(22)), resolution=0.5, qorder=4)]
solution = bem(surfaces, [FluidFilled(1.05, 0.98), FluidFilled(1.8, 0.7)], 250.0;
    parents=[0, 1], incidence_angle=pi / 3, incidence_azimuth=pi / 5)
fig = plot(solution; kind=:surface_field, interfaces=[1, 2],
    interface_alpha=[0.3, 1], colormap=:viridis, incident_arrow=true,
    figure=(size=(900, 580),),
    axis=(azimuth=-0.38pi, elevation=0.24pi, xlabel="x (m)",
        ylabel="y (m)", zlabel="z (m)"))
save("eccentric_pressure.png", fig)

Materials use density and sound-speed ratios relative to the exterior. These mesh settings are for visualization (see numerical convergence for refinement).