Influence of horizontal and vertical rudders on the nature of the movement of a submerged body in a near-surface water environment

Abstract

The study carried out an experimental and theoretical analysis of the influence of protruding parts in the form of aft plumage located in the horizontal and vertical planes on the nature of the movement of a submerged body in the near-surface aquatic environment and its hydrodynamic characteristics. For the first time, experimentally on the basis of the experimental tank, the dependences of the vertical displacement of the body arising under the influence of the lifting force were obtained, and the trim angles of the model were determined when it moved at different speeds. A numerical calculation method is proposed, developed on the basis of the ANSYS 19 R2 Academic Research software package (PC), which makes it possible to determine the nature of wave formation on the water surface, the forces and hydrodynamic moment acting on a body with rudders installed in the aft end from the liquid side when it moves in near-surface water environment at different speeds. The obtained results were compared with the data for a similar body model, without plumage. A significant influence on the dependences of the parameters of the protruding parts under study has been established. The presence of rudders led to an increase in frictional resistance and total drag. An increase in the lifting force acting on the body was also observed, as a result of which the model was more strongly attracted to the water surface at Fr ≈ 0.42, and at high relative speeds of movement, it was stronger repelled from the surface than the model without plumage. The presence of rudders had a significant effect on the trim angle of the model, and on the values of the hydrodynamic moment.