Computational analysis and experimental verification of a boundary integral equation model for tidal turbines

Abstract

Inviscid flow hydrodynamics provides fast computational models for analysis and design. Application to marine current turbines implies the development of suitable models to account for viscosity effects that govern turbine operation over a significant range of operating conditions. The aim of the present work is to analyse the capability of the Viscous Flow Correction (VFC) model combined with a Boundary Integral Equation Model (BIEM) to describe onset flow speed effects on turbine thrust and power. Numerical predictions by BIEM-VFC are compared with results of flume tank tests over a speed range from 0.6 to 2.75 m/s on a 500 mm diameter model turbine in the framework of a research project with industrial partners. Results from this comparative study demonstrate that the simple viscosity correction model is able to capture the effect of onset flow speed, with maximum thrust and power predicted within 3% accuracy at 1.2 m/s and higher.