General Design And Hydrodynamic Calculation Of Propulsive System On Streamline High Speed ROV

With the development and utilization of marine resources,the application of underwater vehicle has been developed rapidly.At present,the installation of offshore platform,the detection of offshore platform,the detection of submarine pipeline,the support of drilling operation,the detection of hydroelectric station and so on are using the open-frame ROV(Remotely Operated Vehicle),which has the characteristics of large power,strong carrying equipment capacity,long time operation under the water and so on.However,most of the open-shelf ROV is huge and needs to be released and recovered by large equipment,which consumes a lot of manpower and material.At the same time,due to the open-frame design of non-streamline shape,the resistance in water is greatly increased,and the anti-current ability is weak.When the current velocity is too fast,its navigation ability will be significantly weakened.When it is necessary to check the condition of the bottom of the ship in the coastal area such as Anchorage,this kind of open-frame ROV can not meet the working conditions.Therefore,a streamline ROV prototype is designed for the bottom detection task in the area with high current velocity.Its appearance refers to the shape of AUV,which can greatly reduce the resistance in the water.At the same time,it connects the mother ship with a cable,and can be remotely controlled by the mother ship to complete the corresponding detection task.The aim of this thesis is to design and install a streamlined ROV prototype for ship bottom detection in a high current velocity area with two longitudinal thrusters,two vertical thrusters and two lateral thrusters.It has the characteristics of small underwater resistance,long working time,fast speed,and ability of carrying various sensors and so on.The study is divided into three parts.On the one hand,this thesis introduces a streamline-shaped ROV shell with reference to the shape of AUV,which includes: a dome with a shape of drips,two transverse channel propeller slots,two vertical channel propeller slots and a tail-balancing wing.This design makes it possible to significantly reduce the resistance during the operation of the High-Speed ROV while increasing the handling performance and the stability performance.On the other hand,the numerical simulation of the ducted propeller and channel propeller is carried out in this thesis.Under open water,the thrust,torque and efficiency curves of ducted propeller are obtained by calculation and simulation.Under the still water,the thrust performance of the channel propeller at different speeds is calculated,and the curve corresponding to the square of the thrust and the speed is drawn.At different speeds,the corresponding thrust and torque are calculated at a certain speed of the channel propeller,and it is found that the channel propeller loses its efficiency at a certain speed.The results obtained by numerical simulation have practical value in engineering and lay a foundation for subsequent motion control.Finally,this thesis introduces the design of an electric control system of the High-Speed ROV,which includes: a sealed cabin for mounting a battery and a control board,a main control board for communicating and controlling the power supply of the underwater equipment,a propeller control board,an operation control box and an upper computer software.Through the experiment in the water,the High-Speed ROV realized the rapid movement and the transmission of the sensor data.