Exam Question

(a) Propeller blade erosion due to cavitation:
Cavitation causes erosion of propeller blades through a progressive damage process. The high-pressure shockwaves created by the collapsing bubbles erode the blade surface material. This process is a type of mechanical corrosion. Initially, the damage may be minor pitting. However, as the process continues, the pits grow larger and deeper, leading to significant material loss and potentially structural weakening of the blade. The erosion is progressive, with small defects growing over time. This necessitates regular inspections and potential repairs or replacements to prevent failure.