The risk of ship suction and disturbance that Cape vessels are prone to when navigating in the restricted waters of the Jiangsu section of the Yangtze River.We propose an inter-ship effect analysis method based on two-dimensional computational fluid dynamics(CFD) simulation and establish a simplified fluid physics model of the intersection process between Cape vessels and small vessels.By setting different relative speeds and lateral spacers,and using dynamic grids and unstructured encrypted regions to construct models,the pressure field,velocity field,vorticity field and streamline evolution laws of the two ships are analyzed when the relative speed of the two ships is 1.0 m/s.The results show that at a distance of 1 times the ship width (50 m),there is a strong suction zone between the two ships.The course deviation of the small vessel can reach 5°,and the duration of the hydrodynamic disturbance between the ships is 15 s.It is determined that the safe distance between the Cape vessel and the small vessel in the restricted waters of Jiangsu section is 50 m.By comparing the PIANC guidelines with the width of the pilotage test track,the recommended value of the minimum dynamic safety distance is proposed.