Hydrodynamic Analysis of Tidal Current Turbine under Water-Sediment Conditions

Abstract

The rivers connecting oceans generally carry sediment due to water and soil losses in China. Additionally, the maximum sediment concentration is 300 g/L, which is much higher than that of other countries. It is unknown whether seawater with sand particles will affect the power of tidal current turbine blades. It is therefore necessary to study the capture power of tidal current turbines in the water-sediment environment. In this study, the blade was divided into a number of transversal airfoil elements based on the blade element theory. The CFD-DPM model was employed to study the lift and drag coefficients of airfoil under multiphase flow, and the fluid–particle interaction was considered. The accuracy of this presented model was assessed using the experimental data of a 120 kW tidal current turbine in a water-sediment environment. Good agreement between the predictions and experimental data was observed. The effect of particle properties on the lift coefficient and the drag coefficient of airfoil were investigated in detail. Furthermore, the 120 kW tidal current turbine power was calculated based on the Blade Element Momentum theory under different particle concentrations. The results show that small diameter particles can improve the tidal current turbine power and the large diameter particle can reduce the power.

BEM Turbine Model and PID Control System of a Floating Hybrid Wind and Current Turbines Integrated Generator System

“…In [3], Equation (33) appears multiplied by the number of blades (B), but in FHYGSYS, Equation ( 33) is applied to each blade element of each of the blades independently, later adding the effect of each of them, considering a different wind vector affecting the blade elements depending on the height, as already explained in previous sections. On the other hand, Equation ( 34) is the one expressed in [3] for the calculation of the differential rotor torque but omitting the radius, thus obtaining the differential force that produces the differential rotor torque indicated in [3].…”

“…Finishing this brief review, in [33]. a model of tidal turbines in a water-sediment environment was presented.…”

Model and Simulation of a Floating Hybrid Wind and Current Turbines Integrated Generator System, Part II: Hydrodynamics and Acting Forces

“…In [1] and in this work, the zones of the tower of the floating system free from the shadow of the wind turbine (h f ree shadow ) and the submerged part of the floating platform (h submerged ) have been divided into these small circular sections. With Equation (50) and the data in Table 7, h f ree shadow is calculated.…”

“…The fluid modeling was performed with ANSYS Fluent [16], and the results were compared with experimental data obtained in [39]. In [50], a model of tidal turbines in a water-sediment environment was presented. The turbine modeling was based on the BEM theory but correcting the values of lift coefficient (C L ) and the drag coefficient (C D ) of each airfoil.…”