REDUCTION ON WAVE SHOALING OVER A LINEAR TRANSITION BY A POROUS MEDIUM

• Main Author: JONATHAN KRISTIANTO (NIM: 10114074), IVAN
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/28182
• Institution: Institut Teknologi Bandung

Waves propagate to the shoreline are experiencing shoaling phenomena. This results in a high increase of wave amplitude due to moving waves from areas with a deeper base leading to areas with a deeper base. In this final project, we will see the effect of a porous media in reducing shoaling wave amplitude. Two models are constructed based on the location of the porous medium. The first model has a base with a linear transition with a porous medium placed on a sloping bottom. In the second model, the porous medium is placed on a flat bottom after the bottom with linear transitions. The model is built based on the Shallow Water Equation (SWE). The analytical solution of the mathematical model is the surface wave function in each domain obtained using the separation variable method. From the analytical solution, we can also obtain the wave transmission coefficient which states the ratio of the amplitude of the transmission wave after passing through the porous medium and the sloping bottom, compared with the amplitude of the incident wave. In addition, the mathematical model obtained is also resolved numerically by the volume method up to the middle grid. For the validation of numerical schemes that have been built, we compare the analytic and numerical solutions. From the comparison it is seen that porous media can reduce shoaling waves with results that confirm their analytical solutions. Furthermore, the dependence of Coefficient transmission values on the properties of porous media will be seen. First the coeffi- cient of friction, then the value of porosity, and the last length of the porous medium. The result, found that both analytically and numerically, the wave reduction effect is directly proportional to the friction coefficient and the width of the porous medium, but inversely proportional to its porosity value.