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S.Salter@ed.ac.uk. S.Salter@ed.ac.uk. Second Oxford Tidal stream Workshop 2013 Are Nearly all Tidal Stream Turbines Designs Wrong?. Stephen Salter Institute for Energy Systems University of Edinburgh S.Salter@ed.ac.uk www.see.ed.ac.uk/~shs. No names, no pack drill. S.Salter@ed.ac.uk.
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S.Salter@ed.ac.uk S.Salter@ed.ac.uk Second Oxford Tidal stream Workshop 2013Are Nearly all Tidal Stream Turbines Designs Wrong? Stephen Salter Institute for Energy Systems University of Edinburgh S.Salter@ed.ac.uk www.see.ed.ac.uk/~shs
No names, no pack drill. S.Salter@ed.ac.uk
. . . just like wind turbines but under water. Frederick Lanchester 1868-1946 Albert Betz 1885-1968
Unswept flow passage ≡ leaky pipes ≡ Vortex wake pollution ≡ Ignorance of flow angles
O’Doherty DM. Mason-Jones A, Morris C, O’DohertyT, Bryne C, Pricket PW, Grosvenor RI. Interaction of marine turbines in close proximity. EWTEC 2011
O’Doherty DM. Mason-Jones, Morris, O’DohertyT, Bryne, Pricket, Grosvenor. Interaction of Marine Turbines in Close Proximity. EWTEC 2011
R.A. McAdam, G.T. Houlsby, M.L.G Oldfield. Structural and Hydrodynamic Model Testing of the Transverse Horizontal Axis Water Turbine. EWTEC 2011
R.A. McAdam , G.T. Houlsby , M.L.G. Oldfield Structural and Hydrodynamic Model Testing of the Transverse Horizontal Axis Water TurbineEWTEC 2011
http://www.google.co.uk/search?q=Tidal+stream+turbine+Alstom&hl=en&client=safari&rls=en&tbm=isch&tbo=u&source=univ&sa=X&ei=BOBOUbPSJY6o0wXh2ICIBw&ved=0CEIQsAQ&biw=1042&bih=1505http://www.google.co.uk/search?q=Tidal+stream+turbine+Alstom&hl=en&client=safari&rls=en&tbm=isch&tbo=u&source=univ&sa=X&ei=BOBOUbPSJY6o0wXh2ICIBw&ved=0CEIQsAQ&biw=1042&bih=1505 Bending moment at blade root
EWTEC Patras 1998 Edinburgh vertical-axis, variable-pitch with rim power take off.
Pitch variation gives control of rotor forces Contra-rotation cancels cross force and torque reaction in wake
Work goes through restricted passage to congested generation space
Second Oxford Tidal stream Workshop 2013Are Nearly all Tidal Stream Turbines Designs Wrong? Stephen Salter Institute for Energy Systems University of Edinburgh S.Salter@ed.ac.uk www.see.ed.ac.uk/~shs
Google images Speed up x 30 Range up x 6000 Payload up x 20,000 Cost per ton-mile down ÷ 100
Laminaria Hyperborea (kelp) are found along the edges of the Pentland Firth at depths up to 30 m. Length can reach 3.5 metres. Cf = ? Google images.
68 mm bob Pentland bed stills. P Hayes. Fisheries Research Aberdeen 2006-8
Friction coefficients for Fshear = 0.5ρ U2 Cf 6.165 TW x 0.04 = 247 GW
EWTEC Patras 1998 Edinburgh vertical-axis, variable-pitch with rim power take off.