Ship hydrodynamics present many unique challenges due to complex geometry, environment, and operating conditions, which results in many complex physics and modelling issues. This is commonly studied through experiments in a towing tank and experiments in a sea keeping and manoeuvring basin. Recently hydrodynamicists have begun to venture into computational prediction of hydrodynamic behaviour of surface ships. Free surface phenomenon around a ship hull plays an important role in its resistance. Wave making resistance comes from the very presence of free surface. Therefore its accurate prediction is very essential for ship design. The flow problem to be simulated is rich in complexity and poses many modelling challenges because of the existence of breaking waves around the ship hull involving two-phase flow, and because of the resolution of thin turbulent boundary layer. The paper aims to computationally estimate the effect of free surface for a moving ship. Commercial software is used for grid generation and flow solution. 1. Solution of a Rudder of a ship in submerged condition. Few different shapes of the rudders are examined. 2. Solution of flow- around a complete ship with free surface. In the present work, flow through the ship hull is computed using a finite volume commercial code, ANSYS 12.1. The ship geometry is modelled using solid modelling software, CATIA V5R9. A three-dimensional structured hexahedral grid is generated using grid generating code, ICEM-CFD V10.0 .Turbulence is modelled with Reynolds Stress model. The resistance of the ship is predicted, and compared against the experimental values. The rudder of the ship is also analyzed. Two different shapes, one wedge shaped and a standard NACA0012 foil, for which experimental results are available in literature, are analyzed. The lift coefficients and flow separation are predicted for different angles of attack using various turbulence models.Computational results are in good agreement with the experimental ones.
"Computational Estimation And RANS Simulation of Free Surface Flow Around A Ship Hull,"
International Journal of Mechanical and Industrial Engineering: Vol. 2
, Article 9.
Available at: https://www.interscience.in/ijmie/vol2/iss2/9