Figure 9.
Abrasive entry and exit at different times: (a) 0.1 s, (b) 0.2 s, (c) 0.3 s, (d) 0.4 s, (e) 0.5 s, (f) 0.6 s, (g) 0.7 s, (h) 0.8 s, (i) 0.9 s.
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