Numerical Simulation of Water Impact on a Wave Energy Converter in Free Fall Motion

Zheng Zheng Hu, Derek Mark Causon, Clive Geoffrey Mingham, Ling Qian

School of Computing, Mathematics and Digital Technology, The Manchester Metropolitan University, Manchester, England.

DOI: 10.4236/ojfd.2013.32014                

Abstract

Results are presented for the 3D numerical simulation of the water impact of a wave energy converter in free fall and subsequent heave motion. The solver, AMAZON-3D, employs a Riemann-based finite volume method on a Cartesian cut cell mesh. The computational domain includes both air and water regions with the air/water boundary captured automatically as a discontinuity in the density field thereby admitting break up and recombination of the free surface. Temporal discretisation uses the artificial compressibility method and a dual time stepping strategy. Cartesian cut cells are used to provide a boundary-fitted grid at all times. The code is validated by experimental data including the free fall of a cone and free decay of a single Manchester Bobber component.

Keywords

Wave Energy Converter; Manchester Bobber; Cartesian Cut Cell; Free Surface Capturing and Artificial Compressibility Method

Conflicts of Interest

The authors declare no conflicts of interest.

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