Session: 09-02-04 WEC Numerical Modeling

Paper Number: 80578

80578 - Comprehensive Verification and Validation of a CFD Analysis 

Wave energy converters (WECs) are designed to operate near the resonance region, being excited at or close to its natural frequencies. Therefore, are strongly affected by the interaction with waves, WEC motion and mooring restraints. Floating WECs, such as point absorbers present small dimensions in relation to the wave length, being typically subjected to large amplitude motions (Mewes, 2020, Palm et al., 2015). An oscillating floating vertical cylinder is a simple representative geometry of WECs and different floating structures. Over the past years it has been addressed in multiple studies revealing several difficulties (Mewes, 2020, Rivera-Arreba, 2017, Palm et al., 2015).

The pitch and heave free decay tests responses of a floating vertical cylinder will be studied throughout this paper. The present case was based on an experiment (Paredes et al., 2015) and subject of different CFD validation studies (Palm et al., 2015, Rivera-Arreba, 2017). Both have found significant discrepancies regarding the damping and natural period of the system, specially for the pitch motion. The proposed test case will be verified and validated with the CFD solver ReFRESCO based on a cell-centered finite-volume discretisation with unstructured grids. A fully unstructured hexahedral grid generator will be used. Furthermore, the results will be compared with the experimental investigation performed by Paredes et al. (2015).

Presenting Author: Tiago Amaral Instituto Superior Técnico

Authors:

Tiago Amaral Instituto Superior Técnico
Manuel Rentschler blueOASIS
Guilherme Vaz blueOASIS
João Baltazar Instituto Superior Técnico