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Chapter 7 

 Conclusions 



This dissertation examines the problem of determining the kinematics of three di- 

 mensional irregular seas from a variety of wave measurements. The presented methods 

 and results lead to the following conclusions: 



• Currently used global methods are inadequate for determining accurately the 

 kinematics of irregular waves. 



— Linear superposition does not satisfy the nonlinear free surface boundary 

 conditions, resulting in large errors in the predicted kinematics near the 

 water surface. 



— Directional spectral methods generally disregard the phase information, 

 making it impossible to determine the detailed kinematics of directional 

 seas. 



— Global methods of high enough order to accurately solve the free surface 

 boundary conditions in three dimensions are prohibitively computationally 

 intensive. 



• The Local Fourier Method for Irregular waves (LFI) can accurately describe the 

 kinematics of two and three dimensional irregular seas by satisfying the full free 

 surface boundary conditions. 



