Proceedings of the Thirty-second (2022) International Ocean and Polar Engineering Conference
Shanghai, China, June 5–10, 2022
Copyright © 2022 by the International Society of Offshore and Polar Engineers (ISOPE)
ISBN 978-1-880653-81-4; ISSN 1098-6189

www.isope.org

Hydrodynamic performance of horizontal axis tidal turbine with different blade pitch angles
Yin Feng, Xiwu Gong, Shuangshuang Xu, Hu Pan

School of Naval Architecture and Maritime, Zhejiang Ocean University.
Zhoushan, Zhejiang, China

on the basis of this analysis, a preliminary pitch design scheme wasproposed, and it was found that the scheme could improve thehydrodynamic performance of vertical axis ocean current power
generation turbines through verification. Zhe Xie (2011) designed andproduced a 1kW horizontal axis pitch turbine prototype, and conductedefficiency experiments based on flow rate and pitch angle turbine,which verified the advantages of low starting flow rate and highefficiency compared with fixed pitch turbine. De Jesus Henriques et al(2016) studied the effect of pitch angle on horizontal shaft power flow
turbines considering the coexistence of wave currents, and found thatincreasing the pitch angle can effectively reduce the effect of waves onwater turbines.

ABSTRACTIn this paper, the performances of horizontal axis tidal turbines withthree different blade pitching angles, i.e., 50°, 60° and 70°, have been
evaluated using STAR-CCM+. The numerical simulation results showthat the larger the pitch angle is, the greater the pressure difference
between the upstream and the downstream surface of the blade is, andthe pitch angle is greatly affected by the force on the impeller in the X
axis direction of the incoming flow. When the pitch angle is increased
from 50° to 60°, the impeller rotation speed increases by 33% and theaverage kinetic energy acquired increases by 77%.

At present, the research on horizontal axis power flow units mainly
focuses on the distribution of the wake field space of power flowenergy units and the interaction law of multiple units, while there arerelatively few studies on the angle of blade pitch. In this paper,
numerical simulations of a horizontal axis power flow energy turbine
are carried out by using the STAR-CCM+ software. The effects ofblade pitch angle on blade lift or resistance performance, impeller force,
impeller energy efficiency and wake field are investigated and analyzed.

KEY WORDS: Tidal current energy; horizontal axis tidal turbine;hydrodynamic performance; CFD; blade pitch angle.

INTRODUCTION
With the rapid development of the global economy and technology, thedemand for energy in human society is increasing. Fossils, coal andother traditional energy sources are facing a situation of imminent
depletion after long-term high-intensity mining and consumption byhuman beings. The long-term large-scale use of fossil energy has led toa series of problems such as environmental pollution, global warming,and rising energy costs (Chen,2019), and the development andutilization of renewable energy has become one of the importancemeasures for the sustainable development of human society. Tidal
energy and other marine energy sources have the advantages of strong
regularity, predictability and high energy density. The horizontal axis
power flow energy turbine as the core device for converting power flowenergy into electrical energy has high energy acquisition efficiency andgood self-starting performance (Wang, 2006; Gao, 2016; Schonbom,2007; Khan, 2009), and has been widely used. For horizontal axis tidal
turbine units, the study of the influence of the pitch angle of the power
flow turbine on the hydrodynamic power of the impeller can provide animportant reference basis for the design of the turbine control system(Gu, 2019).

CALCULATE MODEL
The CFD method is to discretize the basic control equations of fluid
mechanics into a series of mesh nodes to obtain a numerical solution tothe entire flow field (Zhang,2006). In this paper, the CFD software
STAR-CCM+ is used to perform numerical simulation of the tidalturbine.

Control equations
The governing equation are the equation of continuity, the N-Sequation and the energy equation derived from the three fundamental
laws of fluid flow: the law of conservation of mass, the law ofconservation of momentum, and the law of conservation of energy.
The governing equations for incompressible constant viscous fluids
include the continuity equation and the momentum equation,
respectively:

Yonglin Li (2010) conducted velocity analysis and force analysis on
the blades of vertical axis ocean current power generation turbines, and491