PG analysis of data from simulation of NITI cylinder with focal actuation oriented at 45 deg (a–j) and 90 deg (k–t) to fiber direction at 400 Hz. Voxels were included based on criteria from Table 1. Images are from the center slice normal to the z-axis. Row 1: Displacement fields. (a, k) Displacement-field component (⁠$Us$⁠) due to shear waves with slow polarization. (b, l) Displacement-field component (⁠$Uf$⁠) due to shear waves with fast polarization. Row 2: Curl fields. (c, m) Curl-field component (⁠$Γs$⁠) due to shear waves with slow polarization. (d, n) Curl-field component (⁠$Γf$⁠) due to shear waves with fast polarization. Row 3: Phase fields. (e, o) Phase angle (⁠$ψ$⁠) of slow shear wave curl field, $Γs$⁠. Black arrows represent the propagation direction. Arrows only appear over voxels that meet the criteria for inclusion in the analysis (see Table 2). (f, p) Phase angle (⁠$ψ$⁠) of fast shear-wave curl field, $Γf$⁠. In panel (p), there are no arrows showing the propagation direction because no fast voxels for this case meet the criteria for inclusion (see Table 2). Row 4: Fiber-propagation angle. (g, q) Angle between propagation direction and fiber direction (⁠$θ$⁠) for slow voxels that met inclusion criteria. (h, r) Angle between propagation direction and fiber direction (⁠$θ$⁠) for fast voxels that met inclusion criteria. Row 5: Apparent shear modulus. (i, s) Apparent shear modulus (⁠$μapp$⁠) in slow voxels that met inclusion criteria. (j, t) Apparent shear modulus (⁠$μapp$⁠) categorized by fast polarization. In panels (r) and (t), no fast voxels met inclusion criteria. Scale bar in (l) is 5 mm.