|Table of Contents|

 Christopher R. Vogel,Richard H. J. Willden.Improving Tidal Turbine Performance Through Multi-Rotor Fence Configurations[J].Journal of Marine Science and Application,2019,(1):17-25.[doi:10.1007/s11804-019-00072-y]
Click and Copy

Improving Tidal Turbine Performance Through Multi-Rotor Fence Configurations


Improving Tidal Turbine Performance Through Multi-Rotor Fence Configurations
Christopher R. Vogel Richard H. J. Willden
Christopher R. Vogel Richard H. J. Willden
Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, UK
Tidal stream turbinesTidal turbine fencesPower cappingReynolds-Averaged Navier-Stokes simulationBlade element momentum theory
Constructive interference between tidal stream turbines in multi-rotor fence configurations arrayed normally to the flow has been shown analytically, computationally, and experimentally to enhance turbine performance. The increased resistance to bypass flow due to the presence of neighbouring turbines allows a static pressure difference to develop in the channel and entrains a greater flow rate through the rotor swept area. Exploiting the potential improvement in turbine performance requires that turbines either be operated at higher tip speed ratios or that turbines are redesigned in order to increase thrust. Recent studies have demonstrated that multi-scale flow dynamics, in which a distinction is made between device-scale and fence-scale flow events, have an important role in the physics of flow past tidal turbine fences partially spanning larger channels. Although the reduction in flow rate through the fence as the turbine thrust level increases has been previously demonstrated, the within-fence variation in turbine performance, and the consequences for overall farm performance, is less well understood. The impact of turbine design and operating conditions, on the performance of a multi-rotor tidal fence is investigated using Reynolds-Averaged Navier-Stokes embedded blade element actuator disk simulations. Fences consisting of four, six, and eight turbines are simulated, and it is demonstrated that the combination of device- and fence-scale flow effects gives rise to cross-fence thrust and power variation. These cross-fence variations are also a function of turbine thrust, and hence design conditions, although it is shown simple turbine control strategies can be adopted in order to reduce the cross-fence variations and improve overall fence performance. As the number of turbines in the fence, and hence fence length, increases, it is shown that the turbines may be designed or operated to achieve higher thrust levels than if the turbines were not deployed in a fence configuration.


Belloni C, Willden RHJ (2011) Flow field and performance analysis of bidirectional and open-centre ducted tidal turbines. In:Proc 9th European Wave and Tidal Energy Conference, Southampton, United Kingdom
Cooke SC, Willden RHJ, Byrne B, Stallard T, Olczak A (2015)Experimental investigation of tidal turbine partial array theory using porous disks. In:Proc. 11th European Wave and Tidal Energy Conference, Nantes, France
DNV GL (2015) Tidal turbines-rules and standards. Tech Rep. DNV GLST-0164
Draper S, Nishino T (2014) Centred and staggered arrangements of tidal turbines. J Fluid Mech 739:72-93. https://doi.org/10.1017/jfm.2013.593
Fuglsang P, Bak C (2004) Development of the Risø wind turbine airfoils.Wind Energy 7(2):145-162. https://doi.org/10.1002/we.117
Garrett C, Cummins P (2007) The efficiency of a turbine in a tidal channel. J Fluid Mech 588:243-251. https://doi.org/10.1017/S0022112007007781
Glauert H (1935) Airplane propellers. Springer Verlag, Berlin pp 167-269
Mahu R, Popescu F (2011) NREL Phase VI rotor modelling and simulation using ANSYS Fluent 12.1. Math Model Civil Eng 1/2:185-194
McIntosh SC, Fleming CF, Willden, RHJ (2011) Embedded RANS-BEM tidal turbine design. In:Proc. 9th European Wave and Tidal Energy Conference, Southampton, United Kingdom Menter FR (1994) Two-equation eddy-viscosity turbulence models for engineering applications. AIAA J 32(8):1598-1605. https://doi.org/10.2514/3.12149
Nishino T, Willden RHJ (2012) The efficiency of an array of tidal turbines partially blocking a wide channel. J Fluid Mech 708:596-606.https://doi.org/10.1017/jfm.2012.349
Nishino T, Willden RHJ (2013) Two-scale dynamics of flow past a partial cross-stream array of tidal turbines. J Fluid Mech 730:220-244.https://doi.org/10.1017/jfm.2013.340
Schluntz J, Willden RHJ (2015) The effect of blockage on tidal turbine rotor design and performance. Renew Energy 81:432-441. https://doi.org/10.1016/j.renene.2015.02.050
Vogel CR, Willden RHJ (2017a) Designing multi-rotor tidal turbine fences. In:Proc 12th European Wave and Tidal Energy Conference, Cork, Ireland
Vogel CR, Willden RHJ (2017b) Multi-rotor tidal stream turbine fence performance and operation. Int J Marine Energy 19:198-206.https://doi.org/10.1016/j.ijome.2017.08.005
Vogel CR, Willden RHJ, Houlsby GT (2016) Effect of free surface deformation on the extractable power of a finite width turbine array. Renew Energy 88:317-324. https://doi.org/10.1016/j.renene.2015.11.050
Wimshurst A, Willden RHJ (2016) Computational analysis of blockage design tidal turbine rotors. In:Proc. Second International Conference on Renewable Energies Offshore, Lisbon, Portugal


Received date:2017-10-12。
Corresponding author:Richard H. J. Willden,richard.willden@eng.ox.ac.uk
Last Update: 2019-05-14