Hydrodynamic Simulation Analysis And Experimental Research Of Underwater Vehicle

Underwater vehicle is an important tool for underwater observation and operation.The establishment of underwater vehicle hydrodynamic model is the basis of underwater vehicle design and motion control.Traditional hydrodynamic measuring system mainly measures the hydrodynamic forces of underwater vehicles during large-scale underwater direct,diagonal and rotary motion.There is no special testing system to measure the hydrodynamic forces of underwater vehicles under fixed-point and low-speed operating conditions.In order to obtain the hydrodynamic model of the underwater vehicle in working state and measure the hydrodynamic coefficient,a restraint model hydrodynamic test system for measuring the hydrodynamic forces of the underwater vehicle in low-speed linear motion and fixed-point rotary motion was designed and built in the multifunctional water tank of Dalian Maritime University.The hydrodynamic model of underwater vehicle is established,which is divided into inertial hydrodynamic model and viscous hydrodynamic model,and the hydrodynamic coefficient to be measured is defined.In order to obtain the hydrodynamic coefficients of underwater straight and rotary motion,the underwater vehicle hydrodynamic forces are simulated and analyzed.A model of underwater robot with water jet vector propulsion is designed based on the traditional underwater vehicle with propeller propulsion.The model of underwater vehicle is established in ICEM,the calculation domain and boundary layer are determined,the grid independence test is carried out,the wall impact simulation is carried out,and the appropriate wall distance is determined.Fluent simulation is used to obtain the hydrodynamic force of the underwater vehicle in linear and rotary motion.After fitting the simulation curves,the hydrodynamic coefficient of the underwater vehicle simulation is obtained.According to the simulation results,the maximum hydrodynamic force and the appropriate wall distance exerted on the motion of the underwater vehicle are determined.Based on this,the underwater vehicle hydrodynamic test system is designed.The system is divided into towing test system and rotary test system.The towing test system is used to measure the hydrodynamic force of an underwater vehicle model in straight line motion.The rotational test system is used to measure the hydrodynamic force of the underwater vehicle model during its rotational motion.For the strength check of the test system,the equipment of the main test system is selected and the test system is built,and the test flow to.reduce the design deviation is designed.The hydrodynamic forces of the underwater vehicle in straight line motion in different directions and in swing motion in different directions are obtained through tests.The hydrodynamic coefficients of underwater vehicle test are obtained by fitting test curves and compared with those of simulation.The hydrodynamic model of the underwater vehicle is obtained through the hydrodynamic coefficient,which lays a foundation for the motion control of the underwater vehicle.