| Summary: | In the last couple of decades, Arctic Engineering has become a topic of interest. There are still plenty rooms of research to understand the unique characteristic of sea ice, especially in relation to offshore engineering. This includes the most fundamental problem in floating body motion analysis: the radiation-diffraction problem. A powerful mathematical concept, - so called Greens Function – is one of the favourable tools to be used for solving this mathematical problem. This is because the radiation-diffraction problem can be formulated as a boundary value problem expressed by partial differential equations. Although the application is already quite advanced for the open water case, the same cannot be said for the vessel operating in ice infested waters. The integral solution of 3D Greens Function for ice-infested waters which has not been studied before, was derived in this thesis. The open water case is also studied to gain more insight in the implementation of an arbitrary floating body thoroughly. As a closure, interpretation about the difference between open and ice-infested waters is discussed. For Greens Function in the open water case, numerical evaluation of the principal value integral is not straightforward due to the hyperbolic term inside the integrand. This term makes the integrand exceed the limit of floating point number (in MATLAB) and cannot be evaluated into infinity. On the other hand, a numerical integration is quite time consuming (whereas the analytical solution, as far as the writer’s concern, is not found yet). A well-known alternative form of the solution which formulated as an infinite series might improve the computation speed. The rate of convergence depends solely on the ratio of horizontal distance between source and field point (R) and water depth (H). Another numerical issue arises in the deep water case. A finite water depth causes a catastrophic cancellation, both for the integral and the infinite series solution, due to the extremely small difference of the wave number ...
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