A loop system was used to investigate the effect of flow velocity on corrosion behavior of AZ91 D magnesium alloy at an elbow of loop system based on array electrode technology by polarization, computational fluid dynamics(CFD) simulation and surface analysis. The experimental results showed that the corrosion rate increased with increasing flow velocity, and a critical flow velocity could exist in the corrosion of AZ91 D magnesium alloy. When flow velocity exceeded the critical flow velocity, fluid hydrodynamics was dominant in the corrosion of AZ91 D magnesium alloy. On the contrary, the electrochemical factors were dominant.
