Two-dimensional fluid–structure interaction analysis of a vertical axis tidal turbine blade using periodic inflow equivalence model

Int. J. Renew. Energy Dev.

2022

Renewable energy has become an essential energy alternative since the continual depletion of non-renewable energy resources and increasing environmental issues. Tidal energy is a promising future renewable resource which can be extracted using a vertical axis tidal turbine. Since it was proposed, a tidal turbine performance requires improvements which can be obtained by a blade’s trailing edge modification. Modifying the blade’s trailing edge profile is confirmed to be one way to improve a turbine’s work. However, the influence of a trailing edge modifications on a vertical axis tidal turbine blade’s interaction with fluid has not been fully understood, thus the fluid induced vibration as the fluid behaviour working on a vertical axis tidal turbine blade has not been completely discovered. In this paper, 2D fluid-structure interactions of modified vertical axis tidal turbine blades are examined and modelled using OpenFOAM. Three different modified blade profiles are proposed: sharp, rounded, and blunt. The modified profiles are employed to an original NACA 0012 blade and their influences on a vertical axis tidal turbine blade interaction are observed. The result discovers the fluid behaviour and fluid-induced vibrations at all positions (represented by 12 positions) over one turbine’s cycle. The results demonstrate the frequency domain blade velocities and time domain blade displacements for all modified blades. The fluid behaviour around the blade is confirmed by pressure distribution plots over the blade’s upper and lower surfaces. The results show that the blunt profile provides less frequent vibrations due to a reducing vorticity in the downstream fluid regime. However, the vibration amplitude that occurs on the blunt blade is higher than those of rounded and sharp profiles. Based on this research, the blunt trailing edge profile appears to be more favourable to be applied and used for vertical axis tidal turbine blades.

The Effect of Trailing Edge Profile Modifications to Fluid-Structure Interactions of a Vertical Axis Tidal Turbine Blade

Int. J. Renew. Energy Dev.

2022

Numerical Study of a Wind Turbine Blade Modification Using 30° Angle Winglet on Clark Y Foil

EMITTER Int'l J. of Engin. Technol.

Muhammad

Pratilastiarso

et al. 2022

Self Cite

The depletion of fossil fuels and the worsening environment motivate engineers and researchers to explore renewable energy resources. One of the promising renewable energy is wind energy. The wind turbine extracts wind energy to generate electricity. This study aims to modify a wind turbine blade using Clark Y foil to improve the lift force. The modification is employed by forming a winglet profile with a 30° angle on the foils tip. The result shows that the 30° winglet enlarges the lift coefficient to 1.3253 from 1.2795 of the original blade lift coefficient.

A Technique For Lock-In Prediction On A Fluid Structure Interaction Of Naca 0012 Foil With High Re

Turnock

Tan

2020

emitter

Self Cite

A numerical lock-in prediction technique of a NACA 0012 hydrofoil, immersed in a flow having a Re of 3.07x106 is proposed in this paper. The technique observes the foil’s response as part of a fluid-structure interaction analysis. The response is modelled by foil’s vibration which is represented by spring and damper components. The technique identifies and predicts the foil’s lock-in when it vibrates. The prediction is examined using the Phase Averaged Method which employs the Hilbert Transform Method. The aim of this paper is to propose a numerical way to identify a lock-in condition experienced by a NACA 0012 foil in a high Reynolds number flow. The foil’s mechanical properties are selected and its motions are restricted in two modes which are in the pitch and heave directions. The rotational and transverse lock-in modes are identified in the model. The existence of lock-in is verified using pressure distribution plot, the history of trailing edge displacement and fluid regime capture. The history of total force coefficients is also shown to justify the result. The result shows that the technique can predict reliably the lock-in condition on the foil’s interaction. Three main fluid induced vibration frequencies are generated in the interaction. None of them are close to natural frequency of the foil and lock-in is apparently not found in the typical operational condition.