THE INFLUENCE OF TRENCHES ON WAVE HEIGHTTOWARDS THE SHORE WITH SHALLOW WATEREQUATIONS

• Main Author: Samuel Diaz H P, Christophe
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/76105
• Institution: Institut Teknologi Bandung

Trench are long, narrow depressions on the seafloor. Trenches typically have a width of 50 to 100 kilometers, but their length can extend for thousands of kilometers. This phenomenon becomes intriguing to study in order to understand its influence on wave propagation. For the first case, we examine two cases. In this thesis, we will investigate water wave attenuation caused by rectangular trenches using the shallow water equation. Firstly, we will solve this equation using variable separation to obtain the analytical solution for the wave transmission coefficient (Kt) and the optimal trench width for wave reduction. Next, we will develop a numerical scheme to simulate water wave propagation through a rectangular trench and find the value of Kt with finite volume method on a staggered grid. Furthermore, we will compare the analytical solution with the results obtained from the numerical simulation. We will examine the influence of trench depth on the effectiveness of attenuating water waves. For the second case, we will examine the effect of frictional forces on the trench surface on the phenomenon of wave resonance caused by a hardwall. By using the method of separation of variables on the shallow water equation, we obtain an analytical solution in the form of the wave period (T). We will simulate the resonance phenomenon using the analytically obtained wave period. By conducting several simulations, we will determine the minimum friction coefficient (Cf ) on the trench surface that can prevent wave resonance from occurring. We hope that this research will contribute to the field of coastal protection research.