| Summary: | In this thesis, the hydrodynamics of advancing underwater wing profile under ice sheet are studied. This is done by implementing an ice beam model based on FEM to an existing two-dimensional CFD code. First, the mechanism of the ship resistance with and without ice present and wave making process are presented advancing to the problems of hydrodynamic phenomena with ice field. The governing equations behind the YAFFA fluid solver with the boundary conditions and the discretisation are presented. An ice sheet model is developed restricting the case into two dimensional system of Euler-Bernoulli beams. Using finite element method, a system of equations is formed. Different boundary conditions along with the loads and time discretisation are presented. The model is implemented and then verified using the table values for beams with a range of different loads and supports. The effects of mesh density, boundary conditions, the velocity of the wing profile and the ice thickness to ice deflection and non-viscous drag force are studied. Each of the property is varied and the results are presented and analysed. The main findings are following. The surface deformation with ice sheet is considerably different than with free water surface. The drag force is significantly lower with ice sheet and with a high ice thickness the drag force approaches the case with infinitely rigid ice field. The drag force as a function of velocity is of over second degree nature. The accuracy of ice deflection calculation is relatively insensitive to mesh density, boundary conditions and other discretisation errors particularly with thin ice. The accuracy of drag force calculation is greatly sensitive to these factors. Tässä työssä tutkitaan jääkentän alla etenevän siipiprofiilin hydrodynamiikkaa. Työtä varten luotiin kaksiulotteinen jääpalkeista koostuva malli elementtimenelmää käyttäen. Malli liitettiin olemassaolemaan virtausmekaniikan laskentakoodiin. Aluksi esitellään laivan kulkuvastuksen koostumus jään kanssa ja ilman. ...
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