A combined level set/ghost cell immersed boundary representation for floating body simulations. (27th September 2016)

• Record Type: Journal Article
• Authors: Bihs, H.; Kamath, A.
• Is Part Of: International journal for numerical methods in fluids. Volume 83:Number 12(2017)
• Page Start: 905
• Page End: 916
• Publication Date: 2016-09-27
• Subjects: 6DOF -- floating -- level set method -- immersed boundary; Fluid dynamics -- Mathematics -- Periodicals; 532
• DOI: 10.1002/fld.4333
• Languages: English
• ISSNs: 0271-2091

Abstract

Summary: A six degrees of freedom (6DOF) algorithm is implemented in the open‐source CFD code REEF3D. The model solves the incompressible Navier–Stokes equations. Complex free surface dynamics are modeled with the level set method based on a two‐phase flow approach. The convection terms of the velocities and the level set method are treated with a high‐order weighted essentially non‐oscillatory discretization scheme. Together with the level set method for the free surface capturing, this algorithm can model the movement of rigid floating bodies and their interaction with the fluid. The 6DOF algorithm is implemented on a fixed grid. The solid‐fluid interface is represented with a combination of the level set method and ghost cell immersed boundary method. As a result, re‐meshing or overset grids are not necessary. The capability, accuracy, and numerical stability of the new algorithm is shown through benchmark applications for the fluid‐body interaction problem. Copyright © 2016 John Wiley & Sons, Ltd. Abstract : The paper discusses the implementation of a novel six degree of freedom (6DOF) algorithm in the open‐source CFD code REEF3D. The new 6DOF algorithm makes re‐meshing or overset grids unnecessary, resulting in a simpler, faster, and more stable algorithm. Several benchmark applications show that the new floating body algorithm can handle even impact scenarios in a weakly coupled manner while maintaining numerical stability and accuracy.