Research Papers

Ducted Wind Turbine Optimization

[+] Author and Article Information
Ravon Venters

Mechanical and Aeronautical
Engineering Department,
Clarkson University,
Potsdam, NY 13699-5725
e-mail: venterrm@clarkson.edu

Brian T. Helenbrook

Mechanical and Aeronautical
Engineering Department,
Clarkson University,
Potsdam, NY 13699-5725
e-mail: helenbrk@clarkson.edu

Kenneth D. Visser

Associate Professor
Mechanical and Aeronautical
Engineering Department,
Clarkson University,
Potsdam, NY 13699-5725
e-mail: visser@clarkson.edu

1Corresponding author.

Contributed by the Solar Energy Division of ASME for publication in the JOURNAL OF SOLAR ENERGY ENGINEERING: INCLUDING WIND ENERGY AND BUILDING ENERGY CONSERVATION. Manuscript received March 10, 2016; final manuscript received August 1, 2017; published online November 29, 2017. Assoc. Editor: Douglas Cairns.

J. Sol. Energy Eng 140(1), 011005 (Nov 29, 2017) (8 pages) Paper No: SOL-16-1123; doi: 10.1115/1.4037741 History: Received March 10, 2016; Revised August 01, 2017

This study presents a numerical optimization of a ducted wind turbine (DWT) to maximize power output. The cross section of the duct was an Eppler 423 airfoil, which is a cambered airfoil with a high lift coefficient (CL). The rotor was modeled as an actuator disk, and the Reynolds-averaged Navier–Stokes (RANS) k–ε model was used to simulate the flow. The optimization determined the optimal placement and angle for the duct relative to the rotor disk, as well as the optimal coefficient of thrust for the rotor. It was determined that the optimal coefficient of thrust is similar to an open rotor in spite of the fact that the local flow velocity is modified by the duct. The optimal angle of attack of the duct was much larger than the separation angle of attack of the airfoil in a freestream. Large angles of attack did not induce separation on the duct because the expansion caused by the rotor disk helped keep the flow attached. For the same rotor area, the power output of the largest DWT was 66% greater than an open rotor. For the same total cross-sectional area of the entire device, the DWT also outperformed an open rotor, exceeding Betz's limit by a small margin.

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Lilley, G. , and Rainbird, W. , 1956, “ A Preliminary Report on the Design and Performance of Ducted Windmills,” College of Aeronautics Cranfield, Cranfield, UK, Technical Report No. 102.
Foreman, K. , Gilbert, B. , and Oman, R. , 1978, “ Diffuser Augmentation of Wind Turbines,” Sol. Energy, 20(4), pp. 305–311. [CrossRef]
Foreman, K. , and Gilbert, B. , 1979, “ Technical Development of the Diffuser Augmented Wind Turbine (DAWT) Concept,” Wind Eng., 3(3), pp. 153–166.
Igra, O. , 1981, “ Research and Development for Shrouded Wind Turbines,” Energy Convers. Manage., 21(1), pp. 13–48. [CrossRef]
Phillips, D. , Flay, R. , and Nash, T. , 1999, “ Aerodynamic Analysis and Monitoring of the Vortec 7 Diffuser-Augmented Wind Turbine,” Trans. Inst. Prof. Eng. New Zealand, 26(1), pp. 13–19.
Hansen, M. O. L. , Sørensen, N. N. , and Flay, R. , 2000, “ Effect of Placing a Diffuser Around a Wind Turbine,” Wind Energy, 3(4), pp. 207–213. [CrossRef]
Franković, B. , and Vrsalović, I. , 2001, “ New High Profitable Wind Turbines,” Renewable Energy, 24(3–4), pp. 491–499. [CrossRef]
Harvey, N. W. , and Ramsden, K. , 2001, “ A Computational Study of a Novel Turbine Rotor Partial Shroud,” ASME J. Turbomach., 123(3), pp. 534–543. [CrossRef]
Phillips, D. , Richards, P. , and Flay, R. , 2002, “ CFD Modelling and the Development of the Diffuser Augmented Wind Turbine,” Wind Struct., 5(2–4), pp. 267–276. [CrossRef]
Bet, F. , and Grassmann, H. , 2003, “ Upgrading Conventional Wind Turbines,” Renewable Energy, 28(1), pp. 71–78. [CrossRef]
Phillips, D. , 2003, “ An Investigation on Diffuser Augmented Wind Turbine Design,” Ph.D. thesis, University of Auckland, Auckland, New Zealand.
Anzai, A. , Nemoto, Y. , and Ushiyama, I. , 2004, “ Wind Tunnel Analysis of Concentrators for Augmented Wind Turbines,” Wind Eng., 28(5), pp. 605–613. [CrossRef]
Abe, K. , Nishida, M. , Sakurai, A. , Ohya, Y. , Kihara, H. , Wada, E. , and Sato, K. , 2005, “ Experimental and Numerical Investigations of Flow Fields Behind a Small Wind Turbine With a Flanged Diffuser,” J. Wind Eng. Ind. Aerodyn., 93(12), pp. 951–970. [CrossRef]
Watson, S. , Infield, D. , Barton, J. , and Wylie, S. , 2007, “ Modelling of the Performance of a Building-Mounted Ducted Wind Turbine,” J. Phys.: Conf. Ser., 75, p. 012001. [CrossRef]
Jamieson, P. , 2008, “ Beating Betz-Energy Extraction Limits in a Uniform Flow Field,” European Wind Energy Conference (EWEC), Brussels, Belgium, Mar. 31–Apr. 3, pp. 1–10.
Ohya, Y. , Karasudani, T. , Sakurai, A. , Abe, K. , and Inoue, M. , 2008, “ Development of a Shrouded Wind Turbine With a Flanged Diffuser,” J. Wind Eng. Ind. Aerodyn., 96(5), pp. 524–539. [CrossRef]
Kosasih, B. , and Tondelli, A. , 2012, “ Experimental Study of Shrouded Micro-Wind Turbine,” Procedia Eng., 49, pp. 92–98. [CrossRef]
Gaden, D. L. , and Bibeau, E. L. , 2010, “ A Numerical Investigation Into the Effect of Diffusers on the Performance of Hydro Kinetic Turbines Using a Validated Momentum Source Turbine Model,” Renewable Energy, 35(6), pp. 1152–1158. [CrossRef]
Ohya, Y. , and Karasudani, T. , 2010, “ A Shrouded Wind Turbine Generating High Output Power With Wind-Lens Technology,” Energies, 3(4), pp. 634–649. [CrossRef]
Takahashi, S. , Hata, Y. , Ohya, Y. , Karasudani, T. , and Uchida, T. , 2012, “ Behavior of the Blade Tip Vortices of a Wind Turbine Equipped With a Brimmed-Diffuser Shroud,” Energies, 5(12), pp. 5229–5242. [CrossRef]
Kannan, T. S. , Muthasher, S. A. , and Lau, Y. K. , 2013, “ Design and Flow Velocity Simulation of Diffuser Augmented Wind Turbine Using CFD,” J. Eng. Sci. Technol., 8(4), pp. 372–384.
Mansour, K. , and Meskinkhoda, P. , 2014, “ Computational Analysis of Flow Fields Around Flanged Diffusers,” J. Wind Eng. Ind. Aerodyn., 124, pp. 109–120. [CrossRef]
Jafari, S. A. , and Kosasih, B. , 2014, “ Flow Analysis of Shrouded Small Wind Turbine With a Simple Frustum Diffuser With Computational Fluid Dynamics Simulations,” J. Wind Eng. Ind. Aerodyn., 125, pp. 102–110. [CrossRef]
Aranake, A. C. , Lakshminarayan, V. K. , and Duraisamy, K. , 2015, “ Computational Analysis of Shrouded Wind Turbine Configurations Using a 3-Dimensional RANS Solver,” Renewable Energy, 75, pp. 818–832. [CrossRef]
Bontempo, R. , and Manna, M. , 2013, “ Solution of the Flow Over a Non-Uniform Heavily Loaded Ducted Actuator Disk,” J. Fluid Mech., 728, pp. 163–195. [CrossRef]
Bontempo, R. , and Manna, M. , 2014, “ Performance Analysis of Open and Ducted Wind Turbines,” Appl. Energy, 136, pp. 405–416. [CrossRef]
Bontempo, R. , and Manna, M. , 2016, “ Effects of the Duct Thrust on the Performance of Ducted Wind Turbines,” Energy, 99, pp. 274–287. [CrossRef]
Shives, M. , and Crawford, C. , 2011, “ Developing an Empirical Model for Ducted Tidal Turbine Performance Using Numerical Simulation Results,” Proc. Inst. Mech. Eng., Part A, 226(1), pp. 112–125.
Selig, M. S. , and Guglielmo, J. J. , 1997, “ High-Lift Low Reynolds Number Airfoil Design,” J. Aircraft, 34(1), pp. 72–79. [CrossRef]
Eppler, R. , and Somers, D. M. , 1980, “ Supplement to: A Computer Program for the Design and Analysis of Low-Speed Airfoils,” NASA Langley Research Center, Hampton, VA, Report No. NASA-TM-81862.
ANSYS, 2011, “ 14.0 Theory Guide,” ANSYS, Canonsburg, PA, accessed Nov. 15, 2017, https://www.scribd.com/doc/140163383/Ansys-Fluent-14-0-Users-Guide
Rezaei, F. , Roohi, E. , and Pasandideh-Fard, M. , 2013, “ Stall Simulation of Flow Around and Airfoil Using a LES Model and Comparison of RANS Models at Low Angles of Attack,” 15th Conference on Fluid Dynamics, Bandar Abbas, Iran, Dec. 18–20, pp. 1–10.
Menter, F. R. , 2009, “ Review of the Shear-Stress Transport Turbulence Model Experience From an Industrial Perspective,” Int. J. Comput. Fluid Dyn., 23(4), pp. 305–316. [CrossRef]


Grahic Jump Location
Fig. 5

E423 at Re = 3.0 × 105 and 1.0 × 106 compared to experimental data

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Fig. 4

Convergence of k–ε model

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Fig. 3

Domain and mesh used for the airfoil validation study: (a) domain and mesh and (b) boundary layer mesh

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Fig. 2

Eppler 423 airfoil geometry

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Fig. 1

Conceptual design of a DWT. The geometry of the duct's cross section is that of a highly cambered airfoil.

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Fig. 6

E423 at Re = 1.0 × 106: coefficient of pressure and shear stress versus chord length

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Fig. 7

Detail of parameters for duct optimization

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Fig. 11

Velocity contours overlaid by streamlines for the optimal duct configuration

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Fig. 12

Coefficient of pressure and friction for the optimal duct design with c/D = 22.5%

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Fig. 14

Response surface: CT versus AOA for DWT for chord length of 45% at the optimal CP,total

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Fig. 13

Response surface: Δr/D versus Δz/D or chord length of 45% at the optimal CP

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Fig. 8

Domain and mesh for the optimization studies: (a) domain and mesh and (b) magnified region around actuator disk

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Fig. 9

Convergence plot: Cp versus mesh resolution (number of elements)

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Fig. 10

Response surface: CT versus AOA for DWT for chord length of 45% at the optimal CP

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Fig. 15

Response surface: Δr/D versus Δz/D or chord length of 45% at the optimal CP,total



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