ABSTRACT
Although two dimensional theories have their range of applications, they are based on two dimensional cross flow approach and the three dimensional effects are introduced in a simplistic way. The growth of the offshore oil industry throughout the 1970s resulted in the use of structures of a more complex geometry. The analysis of the motions of these structures could not be accomplished by using two dimensional theories. Also, the assumption of slenderness of the hull, the low Froude number and the high frequency range are the basic limitations of this theory. To account properly for the interactions between different sections and the forward speed effects in the free surface boundary condition, it was necessary to move onto three dimensional methods. An early example of the methods is (Garrison 1974, Faltinsen & Michelsen 1974), using a zero forward speed solution.
