Influence of the cross-sectional shape of a submerged body on its hydrodynamic characteristics in free water surface movement

When a submerged body moves in a near-surface water environment, forces and moments act on the liquid, which can have a significant impact on the nature of its movement. It is obvious that the shape of the hull influences the hydrodynamic characteristics of the submerged body. In the given paper, we considered the motion of bodies with different cross-sectional shapes at small depths. The fields of hydrodynamic pressures arising around bodies when moving with different relative velocities were obtained using numerical simulation. The dependency of the wave resistance R_W on models with specified parameters was determined. We established the nature of the change in the values of the lift force F_Z and the trimming moment M_Y for different Froude numbers. With the help of a cable towing system installed in the ice tank, models of submerged bodies were towed. For the first time, the dependencies of the relative vertical displacement of models arising under the influence of the lift force were experimentally obtained, and the trim angles were determined. The relationship between numerical simulation data and experimental results was shown. It was concluded that the values of the studied parameters depend on the prismatic coefficient of the models and the completeness coefficient of the midsection frame.