Abstract: The existence of scour holes around the foundations of offshore wind farms has a detrimental effect on the safe operation of wind turbines,and effective scour protection measures are crucial for stabilizing the sediment around the piles. Taking an offshore wind farm in a Shandong sea area as a research object,this paper proposes the concrete blocks interlocking row protection method which are simplified into a six-column rectangular blocks array model. Based on numerical simulation,the hydrodynamic characteristic of the model is analyzed. It is found that the first row of rectangular blocks is the main force zone of the entire rectangular array model,and the overall drag coefficient of concrete interlocking rows can be evaluated by calculating the first row of individual rectangular block separately,which can significantly reduce the calculation time. In addition,the drag coefficient of blocks changes periodically with flow time,but the amplitude of change with flow time is small.