Paper Type

Master's Thesis


College of Computing, Engineering & Construction

Degree Name

Master of Science in Civil Engineering (MSCE)



NACO controlled Corporate Body

University of North Florida. School of Engineering

First Advisor

Dr. Donald T. Resio

Second Advisor

Dr. William Dally

Third Advisor

Dr. Beyza C. Aslan

Department Chair

Dr. Murat Tiryakioğlu

College Dean

Dr. Mark A. Tumeo


Nonlinear four-wave interactions (Snl) are critical for acquiring realistic spectra needed by operational wave models. High computational demand to calculate these interactions led to an approximation method named the Discrete Interaction Approximation (DIA) to be used broadly in the major operational wave models for a long time. However, the accuracy of the DIA has been controversial since it was first introduced and more precise approximations such as the Two Scale Approximation (TSA in short) are now available. The only issue with the initial TSA`s efficiency is performing an order of a magnitude slower than the DIA in speed. This study questions the exactness of the DIA while trying to increase the competence of the TSA by making improvements on its execution time. Particularly, in this thesis, the main effort is on the local scale term of the TSA since it is the part that consumes the most time while running the code. The findings of this work imply that the TSA can improve its operation speed significantly while maintaining its accuracy with making alterations in the code. By decreasing the number of bands in the local scale it is possible to run the TSA up to 7.5 faster than its initial version.