y Plane z Plane ωx 40 10 1.5 -1.5 -4 -10 -40 Plane Plane I II I II II Plane Plane y -1 flow direction Plane 1.25 2.5 3.75 6.25 7.5 8.75 10 Z (a) h/D = 10% y Plane z Plane ωx 40 10 1.5 -1.5 -4 -10 -40 Plane Plane I II I II II Plane Plane y -1 flow direction Plane 1.25 2.5 3.75 6.25 7.5 8.75 10 Z (b) h/D = 20% Figure 5.13: Streamwise vorticity (ωx ) and streamlines on different Z-Y plane slices, red dashed lines refer to boundary of protrusions 209 . 3.75 5 6. 25 7.5 8.75 10 ω x 40 10 4 1.5 0 -1.5 -4 -10 -40 flow dir ection Plane 2 Plane 1 Plane 7 Plane 4 Plane 6 Plane 5 Plane 3 I I II II II 1 y0 -1 z y (a) h/D = 10% Z 0 1.25 2.5 3.75 5 6. 25. 10 ω x 40 10 4 1.5 0 -1.5 -4 -10 -40 flow directi on Plane 2 Plane 1 Plane 7 Plane 4 Plane 6 Plane 5 Plane 3 I I II II II 1 y0 -1 z y (b) h/D = 20% Figure 5.13: Streamwise vorticity (ω x ) and streamlines on different. vorticity (ω x ) and streamlines on different Z-Y plane slices, red dashed lines refer to boundary of protrusions 209