The Basic Research On The Stray Current

Today's ship and ocean structures often suffer from the corrosions caused by many reasons, one of these reasons is the stray current. Stray current corrosion has been a puzzle that threaten the ship yard and corporation in the whole world, not only in some developed countries, such as Japan and Europe countries, but also in some developing countries, and the finance loss is very huge .Recently many experts in this field have had great interests in this problem, and have made lots of researches on it, however, for many complex affects on the stray current corrosion, so they have no ideal method to solve this problem now. Therefore the further research on the stray current corrosion is very significant.46000t Ships in Dalian New Ship Yard were faced with the stray current corrosion problem. Basing on this detail project, the paper discusses the mechanism of stray current and electrostatic field; finds out the corrosion reason by theory analysis, detect and experiment, and the reason for it is that the leak of the current and the potential gradient; introduces some mathematic methods (FEM, BEM) and describes how the stray current may be modeled numerically using computer modeling. Then by the calculation of the detailed model using FEM, some effective measures could be adopted to solve the corrosion problem in Dalian New Shipyard, such as the cathodic protection and the electrostatics shield. Finial some significative conclusions for the electrostatic field could be concluded, which are the basis for the further research.