Experimental and numerical characterisation of a 2D wave flume

Abstract

A wave flume of 12.5 x 0.6 x 0.7 m (length x width x height) able

to reproduce the ocean conditions of the most representative

research facilities in the Basque Country (BiMEP-Biscay

Marine Energy Platform and Mutriku Wave Energy Plant) has

been recently installed at the laboratory of Fluid Mechanics

of the Faculty of Engineering in Bilbao. This new facility has

the capacity of producing a wide range of monochromatic

and panchromatic waves by a piston-type wavemaker. Several

ultrasonic wave probes measure the surface elevation, and the

wave energy is dissipated in a passive parabolic beach in order to

diminish significantly the reflection along the flume.

A numerical model based on Reynolds Averaged Navier

Stokes (RANS) equations has been developed to represent

the turbulence and Eulerian Volume of Fluid (VOF) unsteady

approach in STAR-CCM+ CFD code to track the evolution of the

free surface.

This numerical model has been validated with the corresponding

experimental campaign covering a wide range of depths,

wave heights, wavelengths and periods. Tests focused on the

description of the basic hydrodynamic processes of wave

generation and propagation, giving as a result the definition

of the wavemaker to produce the required wave. Results were

analysed together with the analytical solution based on potential

flow theory. The experiments carried out in the present study

establish the operational limits of the wave flume in terms

of wave generation, propagation and extinction, defining the

operational range of future experimental campaigns where wave

interaction with floating structures, wave energy converters and

mooring systems will be studied.