Study of sacrificial cathodic protection on marine structures in sea and fresh water in relation to flow conditions

The extent of corrosion between a miniature steel ship model at different relative velocities of sea water fitted with commercial sacrificial anodes of aluminium (Al) in sea water and magnesium (Mg) in fresh water is studied. The experimental results show that the degree of cathodic protection represented by the cathode potential at a given distance from different types of sacrificial anodes decreases slightly with an increase in the relative velocity. The results also show that the amount of Al or Mg required to protect the ship cathodically increases as the relative velocity increases.