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NNMREC Arshiya Hoseyni Chime University of Washington Northwest National Marine Renewable Energy Center MSME Thesis Defense December 10 th, 2013

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NNMREC US Water Resources & Usage 2 Water Resources Water Usage

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NNMREC US Water Usage & Distribution 3

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NNMREC US Water Usage & Distribution 4 Washington

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NNMREC Columbia Basin Project US Bureau of Reclamation manages more than 47,000 miles of canals, drainages, and tunnels Columbia Basin Project 6,000 miles of channels 671,000 acres of farmlands 300 miles of main channel High flow rate capacity 5

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NNMREC Flow Control High Hills Gates Courtesy of Professor Malte Tainter Gates 6

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NNMREC Open Channel Flow Analysis Conservation of energy Fr 2 >1 => Supercritical Flow => Hydraulic Jump Conservation of Momentum 7 CV1 CV2

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NNMREC Motivation Opportunity: Hydrokinetic turbines for flow control and power generation 8

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NNMREC Motivation Pros Unidirectional Flow Cheaper than traditional hydropower (Dams) Easier permitting than tidal turbines Cons Small-scale power generation Farmers may not like the change from traditional control to new control 9

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NNMREC Approach 1-D theoretical modeling 3-D CFD modeling Turbines Actuator Disc Model Virtual Blade Model Comparison between models 10

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NNMREC Approach 1-D theoretical modeling 3-D CFD modeling Turbines Actuator Disc Model Virtual Blade Model Comparison between models 11

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NNMREC 1-D Theory- Linear Momentum Theory Unconstrained Channel Power Coefficient 12 Betz limit

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NNMREC 1-D Theory-Linear Momentum with blockage effects Constrained Channel Blockage Ratio Top View 13

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NNMREC Constrained Channel Assumptions: No wake rotation No drag force No friction loss Uniform water depth at 3,4 and 5 4 Equations, 4 Unknowns (u 3, u 4, h 3, h 5 ) 14 1-D Theory-Linear Momentum with blockage effects

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NNMREC Constrained Channel Assumptions: No wake rotation No drag force No friction loss Uniform water depth at 3,4 and 5 4 Equations, 4 Unknowns (u 3, u 4, h 3, h 5 ) 15 1-D Theory-Linear Momentum with blockage effects

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NNMREC 1-D Theory- Channel Constriction Flow rate is constant Blockage Ratio is increased 5.1 m 5 m 4.937 m 16 m 21 m 26 m 4m 16 BR=0.36 BR=0.48 4m

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NNMREC Effect of Channel Constriction on Water Depth 17

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NNMREC Effect of Channel Constriction on Power Generation 18

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NNMREC Approach 1-D theoretical modeling 3-D CFD modeling Turbines Actuator Disc Model Virtual Blade Model Comparison between models 19

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NNMREC CFD- ADM, VBM ANSYS Fluent14.0 RANS Equations SST turbulence model Coupled Pseudo-Transient Solver Volume of Fluid Model Free surface is at VF=0.5 20

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NNMREC CFD-Meshing Number of cells 16m wide channel3.3 million 21m wide channel4.2 million 21

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NNMREC CFD-Boundary Conditions Mass flow inlet Pressure outlet No slip at walls D=4 m t= 0.2 m water air 30 m60 m 5 m 2.5 m 132,850 kg/s 50 kg/s 2.5 m 3 turbines(4m diameter) Turbulence BC: 22

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NNMREC Approach 1-D theoretical modeling 3-D CFD modeling Turbines Actuator Disc Model Virtual Blade Model Comparison between models 23

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NNMREC CFD-Actuator Disc Model Porous Media Model C2 is inertial resistance of the porous media P is based on 1-D theory at a given induction factor 24

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NNMREC ADM- Velocity Contours BR=0.36 Fr=0.18 BR=0.48 Fr=0.24 25

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NNMREC ADM- Normalized Velocity BR=0.36 Fr=0.18 BR=0.48 Fr=0.24 26 Normalized Velocity Normalized water depth

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NNMREC ADM- Dynamic Pressure BR=0.36 Fr=0.18 BR=0.48 Fr=0.24 27

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NNMREC Free Surface Elevation-Subcritical 28 Channel Length [m] Normalized Surface Elevation

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NNMREC Supercritical(16m) Induction factor=0.6 Outlet depth and Inertial Resistance from 1-D theory 29 Velocity [m/s]

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NNMREC 1-D theoretical modeling 3-D CFD modeling Turbines Actuator Disc Model Virtual Blade Model Comparison between models Approach 30

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NNMREC CFD-Virtual Blade Model Blade Element Theory VBM Input: Tip effect=96% 31

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NNMREC VBM- Blade Design 32 Bahaj, 2004 c=50cm c=40cm Chord Distribution

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NNMREC VBM-Cavitation Analysis Cavitation occurs when local pressure is lower than vapor pressure 33

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NNMREC VBM- Cavitation Analysis 34

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NNMREC VBM- Cavitation Analysis Cavitation number Cavitation occurs 35

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NNMREC Cavitation- Pitching limit 36 Cavitation Number at the tip TSR=5

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NNMREC Operating Condition TSR=5 Pitch the blades from -5 to 10 as long as AOA