Current Research | Renewable Energy

A Study on Oscillating Foil Energy Harvester with a Passive Flexible Foil

(Supported by Lloyd's Register Group Limited)

By Wendi Liu, Dr Qing Xiao

The present research is an extension of our previous work, which indicated that a flexible foil has a positive contribution to the energy extraction enhancement with an oscillating foil energy device. Other than an active controlled foil bending in Liu et al 2013, by prescribing the deformation of foil, the current research investigates the passive motion of flexible foil and its effect on energy extraction efficiency. To achieve this goal, the coupled Fluid-Structure interaction solver is used. The preliminary results obtained so far show that such a passive controlled flexible foil can increase efficiency as much as 12% than a rigid foil.

First, we test the FSI calculation part of our code and get a good agreement with past paper.

A NACA0012 oscillating foil device is simulated in current research. Rigid and flexible blade is compared in terms of the energy extraction efficiency. Our results show that the amplitude of lift force coefficient (Cl) is enlarged with a flexible blade. A phase lag between rigid and flexible blade is observed from the instantaneous lift force coefficient curve. The amplitude of moment coefficient is also enhanced by replacing the blade from rigid into flexible type. Since power coefficient (Cop) is a combination of the contribution from Cl and Cm, for oscillating foil turbine, flexible blade is better than rigid one. The preliminary results obtained so far show that such a passive controlled flexible foil can increase efficiency as much as 12% than a rigid foil.

Figure comes from the internet

Please refer to:

Wendi Liu and Qing Xiao. "A Study on Oscillating Foil Energy Harvester with a Passive Flexible Foil." AWTEC(2014) 00657.

Wendi Liu, Qing Xiao and Qiang Zhu. "Passive Flexibility Effect on Oscillating Foil Energy Harvester." AIAA Journal (2016).

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