Journal of Marine Science and Engineering Article Analysis of Different Methods for Wave Generation and Absorption in a CFD-Based Numerical Wave Tank Adria Moreno Miquel 1 ID , Arun Kamath 2,* ID , Mayilvahanan Alagan Chella 3 ID , Renata Archetti 1 ID and Hans Bihs 2 ID 1 Department of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, Via Terracini 28, 40131 Bologna, Italy;
[email protected] (A.M.M.);
[email protected] (R.A.) 2 Department of Civil and Environmental Engineering, NTNU Trondheim, 7491 Trondheim, Norway;
[email protected] 3 Department of Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, IN 46556, USA;
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[email protected] Received: 30 April 2018; Accepted: 10 June 2018; Published: 14 June 2018 Abstract: In this paper, the performance of different wave generation and absorption methods in computational fluid dynamics (CFD)-based numerical wave tanks (NWTs) is analyzed. The open-source CFD code REEF3D is used, which solves the Reynolds-averaged Navier–Stokes (RANS) equations to simulate two-phase flow problems. The water surface is computed with the level set method (LSM), and turbulence is modeled with the k-w model. The NWT includes different methods to generate and absorb waves: the relaxation method, the Dirichlet-type method and active wave absorption. A sensitivity analysis has been conducted in order to quantify and compare the differences in terms of absorption quality between these methods. A reflection analysis based on an arbitrary number of wave gauges has been adopted to conduct the study. Tests include reflection analysis of linear, second- and fifth-order Stokes waves, solitary waves, cnoidal waves and irregular waves generated in an NWT.