Abstract
A labscale flappingtype turbine with a semipassive activation mode has been designed and implemented. A nonlinear dynamic model, developed in our previous work, is validated by a series of experiments along with computational fluid dynamics (CFD) simulations. Previously, the dynamic model was used only to estimate the dynamic response of a flappingtype turbine. In this work, the applicability of the dynamic model is extended to estimate the hydrodynamic forces, extracted power, and efficiency. It was demonstrated from a comparison of the CFD results and measured values that the dynamic model based on a quasisteady approach estimates the aforementioned performance parameters of measurements well in cases particularly with a low effective angle of attack, thus demonstrating the usefulness of the dynamic model for a flappingtype turbine at an early stage.
Similar content being viewed by others
Abbreviations
 \(\bar{c}\) :

Chord length of the hydrofoil, m
 B :

Span of the hydrofoil, m
 x _{ p } :

Pitching axis location from the leading edge, c
 ψ :

Flapping angle, °
 θ :

Pitching angle, °
 l :

Flapping arm length, m
 m :

Mass of the flapping arm and or hydrofoil, kg
 V :

Volume of the flapping arm and or hydrofoil, m^{3}
 FB :

Buoyancy force of the flapping arm and or hydrofoil, N
 W:

Weight of the flapping arm and or hydrofoil, N
 x _{ l } :

Center of Mass location of the flapping arm from the flapping axis, m
 x _{ c } :

Center of Mass location of the hydrofoil from the leading edge, m
 \(O(x,y,t)\) :

Real coordinate system
 \(O'(x',y',t')\) :

Image coordinate system
 \(\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\frown}$}}{C}\) :

Transformation matrix
 c _{ x } :

Transformation coefficient of the xaxis
 c _{ y } :

Transformation coefficient of the yaxis
 c _{ t } :

Transformation coefficient of the time
 x _{ {A,B,P,Q,R} } :

Position of marker A,B,P,Q,R at the xaxis
 y _{ {A,B,P,Q,R} } :

Position of marker A,B,P,Q,R at the yaxis
 s _{ N } :

Fitting function with N number of linear combination of sine and cosine functions
 a _{ n } :

Nth coefficient of the sine function
 b _{ n } :

Nth coefficient of the cosine function
 V _{ ∞ } :

Far field inflow velocity, m s^{−1}
 V _{ f } :

Induced or deflected flow velocity, m s^{−1}
 W :

Relative flow velocity, m s^{−1}
 I:

Mass moment of inertia of the flapping arm and the hydrofoil about the flapping axis, kg.m^{2}
 Ig :

Equivalent mass moment of inertia of the gearbox about the driving gear axis, kg.m^{2}
 \(\dot{\psi }\) :

Angular speed of the flapping arm, rad s^{−1}
 \(\ddot{\psi }\) :

Angular acceleration of the flapping arm, rad s^{−2}
 γ :

Deflection angle of the flow, °
 ρ :

Density of the water, kg.m^{−3}
 C _{ L } :

Lift coefficient of the hydrofoil
 C _{ D } :

Drag coefficient of the hydrofoil
 C _{ M } :

Moment coefficient of the hydrofoil
 S :

Projected surface area of the hydrofoil, m^{2}
 C :

Damping coefficient of the transmission system, N m s
 F _{ x } :

Horizontal force, N
 F _{ y } :

Vertical force, N
 L :

Lift force, N
 D :

Drag force, N
 Τ :

Measured holding torque, N.m
 M _{ c/4 } :

Pitching moment, N.m
 M _{ A } :

Mathematical holding torque in the dynamic model, N m
 M _{ LD } :

Moment about the flapping axis due to lift and drag, N m
 M _{ H } :

Total moment about the flapping axis, N m
 Re:

Reynolds number
 Υ:

Kinematic viscosity, m^{2} s^{−1}
 d:

Maximum swept distance of the hydrofoil, m
 P(t) :

Measured instantaneous power, W
 Ω(t) :

Measured instantaneous angular velocity of the output shaft, rad s^{−1}
 P _{ F } :

Available power from the flow stream, W
 P _{ E } (t):

Measured instantaneous extracted power at the output shaft, W
 P _{ H } (t):

Instantaneous generated power due to pure hydrodynamic forces, W
 P _{ c/4 } (t):

Instantaneous power due to pitching moment, W
 \(\bar{P}\) :

Averaged extracted power, W
 \(\bar{P}_{H}\) :

Averaged hydrodynamic power, W
 Η :

Power extraction efficiency, %
 η _{ H } :

Hydrodynamic power efficiency, %
 f* :

Reduced frequency
 ψ _{ m } :

Measured flapping angle, °
 ψ _{ e } :

Estimated flapping angle, °
 ψ _{ reference } :

Reference flapping angle (CFD or measured), °
 α :

Effective angle of attack, °
 V _{ x } :

Horizontal velocity at the pitch axis, m s^{−1}
 V _{ y } :

Vertical velocity at the pitch axis, m s^{−1}
 P _{ x } :

Power due to horizontal force component, W
 P _{ y } :

Power due to vertical force component, W
 TB_{i} :

Ith timing belt
 G_{i} :

Ith gear
 CW:

Clock wise rotational direction of the output shaft
 CCW:

Counter clock wise rotational direction of the output shaft
References
Aerovironment Nano Hummingbird, http://www.avinc.com/nano. Accessed 25 Feb 2015
FESTO SmartBird, http://www.festo.com/cms/en_corp/11369.htm. Accessed 25 Feb 2015
IHC Engineering Business Ltd., Stingray Tidal Stream Generator. http://www.engb.com. Accessed 25 Feb 2015
Pulse Generation Ltd., Hydrofoils of Turbines http://www.pulsetidal.com. Accessed 25 Feb 2015
BioPower Systems, http://www.biopowersystems.com. Accessed 25 Feb 2015
Aniprop, http://www.aniprop.de/dlrhp. Accessed 25 Feb 2015
DualWingGenerator, http://www.festo.com/cms/en_corp/13707.htm. Accessed 25 Feb 2015
Mc Kinney W, De Laurier J (1981) Wingmill: an oscillatingwing windmill. J Energy 5(2):109–115
Young J, Ashraf MA, Lai JCS, Platzer MF (2013) Numerical simulation of fully passive flapping foil power generation. AIAA J 51(11):2727–2739
Le TQ, Ko JH, Byun D (2013) Morphological effect of a scallop shell on a flappingtype tidal stream generator. Bioinspiration Biomim 8:3
Kinsey T, Dumas G (2008) Parametric study of an oscillating airfoil in a powerextraction regime. AIAA J 46(6):1318–1330
Kinsey T, Dumas G, Lalande G, Ruel J, Mehut A, Viarouge P, Lemay J, Jean Y (2010) Prototype testing of a hydrokinetic turbine based on oscillating hydrofoils. Renew Energy 36:1710–1718
Kinsey T, Dumas G (2012) Computational fluid dynamics analysis of a hydrokinetic turbine based on oscillating hydrofoils. J Fluids Eng 134:1–16
Truong QT, Sitorus PE, Park HC, Tambunan IH, Hendra AP, Ko JH, Kang TS (2013) Dynamic model for flappingtype tidal energy harvester. In: Proceedings of the 9th International Conference on Intelligent Unmanned System (ICIUS), India
Truong QT, Sitorus PE, Park HC, Tambunan IH, Hendra AP, Ko JH, Kang TS (2014) Nonlinear dynamic model for flappingtype tidal energy harvester. J Mar Sci Tech 19:406–414
Park HC, Kang TS, Nguyen QV, Truong QT, Sitorus PE, Ko JH, Lee KS (2014) Repeating rise and fall tidal current generator. WO Patent No. WO/2014/017859 (A1)
Park HC, Kang TS, Nguyen QV, Truong QT, Sitorus PE, Ko JH, Lee KS (2014) Oscillating tidal stream power generator. Korea Patent No. KR101352417 (B1)
Sitorus PE, Truong QT, Le QT, Tambuan IH, Park HC, Kang TS, Ko JH (2013) Progress on development of flappingtype tidal energy harvester in KIOST. In: Proceedings of IEEE Conference on Clean Energy and Technology (CEAT) Malaysia
Hedrick TL (2008) Software techniques for two and threedimensional kinematic measurements of biological and biomimetic systems. Bioinspiration Biomim 3:3
Truong TV, Le TQ, Byun DY, Park HC, Kim MJ (2012) Flexible wing kinematics of a freeflying beetle (rhinoceros beetle, Trypoxylus Dichotomus). J Bionic Eng 9(2):177–184
Sheidahi RE, Klimes PC (1981) Aerodynamic characteristics of seven symmetrical airfoil sections through 180degree angle of attack for use in aerodynamic analysis of vertical axis wind turbines. Sandia National Laboratories Energy Report, United States of America
Park SH, Kwon JH (2004) Implementation of k–ω turbulence models in an implicit multigrid method. AIAA J 42:1348–1357
Park SH, Lee JE, Kwon JH (2006) Preconditioned HLLE method for flows at all Mach numbers. AIAA J 44:2645–2653
Le TQ, Han IS, Park SH, Ko JH (2012) High power extracted from flexible flapping tidal generator. Asian Wave and Tidal Energy Conference. Hyatt Hotel, Jeju Island, Korea
Xiao Q, Liao W, Yang S, Peng Y (2012) How motion trajectory affects energy extraction performance of a biomimic energy generator with an oscillating foil. Renew Energy 37:61–75
Tambunan IH, Kang TS, Putra HA, Park HC, Ko JH (2013) Control system design for flapping type tidal energy harvester. In: Proceeding of the 9th International Conference on Intelligent Unmanned System, India
MathWorks^{R} (2013) Matlab: User’s Guide (R2013a). https://www.mathworks.com/help/pdf_doc/matlab/math.pdf. Accessed 25 Feb 2015
McCroskey WJ (1982) Unsteady airfoils. Annu Rev Fluid Mech 14:285–311
Acknowledgments
This work was a part of a project entitled the “Development of ActiveControlled Tidal Stream Generation Technology” funded by the Ministry of Oceans and Fisheries, Korea (20110171) and a part of a project entitled the “Core Technology Development for Harnessing Ocean Energy” funded by Korea Institute of Ocean Science and Technology (PE99323).
Author information
Authors and Affiliations
Corresponding author
About this article
Cite this article
Sitorus, P.E., Le, T.Q., Ko, J.H. et al. Design, implementation, and power estimation of a labscale flappingtype turbine. J Mar Sci Technol 21, 115–128 (2016). https://doi.org/10.1007/s007730150336z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s007730150336z