Research On Hydrodynamic Interaction During The Docking Process Between DSRV And Wrecked Submarine

With the birth of the submarine,how to rescue the wrecked submarine has been a topic of discussion among researchers.In order to avoid the tragedy of the death of all crewmen of the Russian Navy "Kursk" nuclear submarine due to the failure of the rescue after the crash,the naval powers pay more attention to the development of submarine rescue equipment.The deep submergence rescue vehicle(DSRV)is currently the most recommended rescue equipment for the submarine rescue in many countries,and its hydrodynamic characteristics also directly affect the efficiency of mission completion.During the entire rescue process,the connection between the DSRV and the wrecked submarine is particularly important.As the DSRV approaches the wrecked submarine,its hydrodynamic force will inevitably be affected by the submarine flow field.The content of this paper is the change of hydrodynamics in the process of lifeboat approaching the wrecked submarine in different modes of motion,and the difference in the hydrodynamic force when the DSRV is docked with the different submarine exits,thus providing corresponding operations for the drivers of DSRV.In this paper,the computational fluid dynamics method is used to simulate the flow field of the submarine model-SUBOFF in the unbounded flow direct state.The accuracy of the flow field numerical simulation is verified by comparing the calculated value with the experimental value.At the same time,the meshing method,the boundary layer processing method and the selection of the turbulence model are discussed,which will provide reference for the hydrodynamic calculation of DSRV.Secondly,the DSRV model will be used for direct navigation and dive in the unbounded flow.The numerical simulation results of the working conditions are compared with the experimental values.While demonstrating the feasibility of the numerical simulation method of the hydrodynamics of the submarine lifeboat,it also proves that the overlapping grid technique can be applied to the computational simulation of multi-body motion.Finally,the above verifications are adopted.The method of studying the DSRV in the face of different inflow speeds,the hovering,uniform speed dive,etc.in the flow field of the wrecked submarine is subject to the variation of the hydrodynamic force with the distance between the two boats;Under the same inflow condition and the same dive speed,the DSRV docked with exits at different positions.Differences of hydrodynamic forces,assistance and advice to select potential DSRV and wrecked submarine docked position.According to the above research,the hydrodynamic force that the DSRV receives when it is hovering in a positive floating position at different positions near the submarine is as follows:when the DSRV is far away from the rescued submarine,it is subjected to upward lift;when the distance is gradually reduced,the lift is followed.Weaken until it becomes suction;when the DSRV is about to dock,it will be subjected to upward lift.When the DSRV dive at a low speed near the lifeboat,it is subjected to greater lift and heading torque than the hovering condition.When the DSRV is docked with the exit behind the submarine's fairwater and the exit near the nacelle,it receives more resistance at the rear of the submarine than at the rear of the fairwater,and the DSRV is less affected by the lift and pitch moments at the tail.In the case of the impact behind the fairwater,therefore,it is recommended that the DSRV should be docked with the rear exit,as conditions permit,to appropriately reduce the DSRV's interference from the wrecked submarine.