Second Oxford Tidal stream Workshop 2013 Are Nearly all Tidal Stream Turbines Designs Wrong? Stephen Salter Institute for Energy Systems University of Edinburgh
No names, no pack drill.
... just like wind turbines but under water. Frederick Lanchester Albert Betz
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 Turbine EWTEC 2011
Open flow field Duct
Bending moment at blade root s=en&tbm=isch&tbo=u&source=univ&sa=X&ei=BOBOUbPSJY6o0wXh2ICIBw&ved=0CE IQsAQ&biw=1042&bih=1505
GOOGLE IMAGES
NASA
Edinburgh vertical-axis, variable-pitch with rim power take off. EWTEC Patras 1998
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 2013 Are Nearly all Tidal Stream Turbines Designs Wrong? Stephen Salter Institute for Energy Systems University of Edinburgh
Google images
Speed up x 30 Range up x 6000 Payload up x 20,000 Cost per ton-mile down ÷ 100 Google images
Something for the simpletons
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.
Pentland bed stills. P Hayes. Fisheries Research Aberdeen mm bob
Friction coefficients for Fshear = 0.5 ρ U 2 Cf TW x 0.04 = 247 GW
Edinburgh vertical-axis, variable-pitch with rim power take off. EWTEC Patras 1998