| The thrust-vectoring technology of waterjet propulsion submarine is a high integration of the vectoring deflection techn ology of the nozzle and the propulsion technology of submarine.The internal flow conditions and thrust-vectoring characteristics of the spiral-mixed flow waterjet propulsion submarine are studied with different deflection angle of nozzle and variable rota tional speeds.The research contents provide an important reference for the study of the internal flow and thrust performance of the waterjet propulsion submersible.Therefore,the system combines with submarine body,the spiral-mixed flow waterjet propulsion pump and the axisymmetric vectoring nozzle took as the research object.This paper focuses on the change law of the vectoring thrust and resistance and the affection of internal flow field under different deflection of the vectoring nozzle and the diff erent rotational speeds.This article mainly contents and the conclusions are as follows.(1)In the three-dimensional coordinate system,the geometric azimuth angle and the geometrical deflection angle of the nozzle deflection angle are defined.At first,the change law of the thrust and resistance and the internal flow characteristics of the submarine when the deflection angle of nozzle is 0 ° is calculated under different sailing velocity or different rotational speeds.It is concluded that under the same rotational speed,the thrust of the propulsion pump does not change with the change of the sailing velocity,but the resistance has obvious increase.In addition,the starting rotational speed and the rotational speed at uniform speed 2m/s of the submarine are obtained.(2)The navigation status of propeller is divided into six states.The six states include that pitch,yaw and pitching yaw,each of which has a typical geometrical deflection angle of 0°,15°,30° and 45°.At each angle,the waterjet propulsion submarine is geometry modeled,mesh divided and numerically simulated under 5 different rotational speeds.The change law of thrust is studied under the 19 kinds deflection angle of nozzle.The change rule of thrust with the change of geometrical deflection angle and the increasing of rotational speeds of propulsion pump under six kinds of navigation conditions is obtained.The total thrust increment coefficient increases with the increase of rotational speed,and the increase amplitude of total thrust increases.Under the same rotational speed and navigation status,the vectoring change of the thrust varies with the increase of the angle,but the same is that the flow velocity of one side with large curvature of the nozzle increases faster,and the submersible is easy to get larger thrust.(3)The internal flow field of 6 kinds and 45°extreme deflection angles is analyzed,and the relationship between the flow field and the thrust variation of the nozzle is obtained.The corresponding relationship between the change of rotational speed and the flow change of the inner flow field is gained.The deflection of the nozzle has great influence on the guide vane and the internal flow state of the nozzle.When the nozzle is deflected,the velocity gradient on a side with a large flow curvature is large than a side with a small flow curvature.With the increase of rotational speed,the velocity gradient on the inner of the guide vane and nozzle increases,and the separation of the flow field near the centrifugal transition section becomes more obvious.At each rotational speed,the total thrust is the largest with the upper-left 45°state of nozzle.The variation range of the total thrust coefficient is small with nozzle in the right yaw state,which indicates that the increment of thrust is small.The variation range of the total thrust coefficient is maximum with nozzle at the upper-left 45°state,which indicating that the increment of thrust is most obvious in this deflection direction. |
PDF Full Text Request