Author(s): R. Divya; V. Sriram

Linked Author(s): Sriram V

Keywords: IMLPG-R; FNPT; Porous rate: Vegetation density

Abstract: This paper presents a three-dimensional model for wave vegetation interaction developed by coupling meshless and a mesh-based method. Improved Meshless Local Petrov-Galerkin method with Rankine source (IMLPG-R) is used for the vegetation region and Fully Non-Linear Potential flow theory (FNPT) based on Finite Element Method (FEM) is used in wave generation region. The coupling is done at a particular zone where the field variables are transferred from mesh-based method to meshless method. The IMLPG-R method is applied for unified Navier stokes equation with additional drag and inertia force term representing the vegetation. This study is based on macroscopic model where the vegetation region is considered as a wave pressure and kinematics reduction zone, due to the additional forces caused by vegetation. The additional forces depend on the vegetation density and dimension, which is represented in a variable named porous rate. This porous rate value is unity at pure fluid region and less than unity on the vegetation region. A transition region is provided where the porous rate gradually decreases from unity. The mesh-based method is two dimensional and less time consuming, hence it is used in the region where wave generation is done. In the coupling zone the wave parameters from 2D FNPT model are transferred to the particles of 3D IMLPG-R model which is further progressed over the vegetation region. With this type of coupling between two models the advantage of both the FNPT and IMLPG-R model is used. This paper is an attempt to further increase the scope of hybrid models in wave vegetation interaction to bring more realistic wave scenarios into simulation. The developed 3D model is validated using available experimental results and good agreement was obtained.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p1152-cd

Year: 2023