Experimental of Three Parallel Water Current Turbine with Optimized Straight Blades and Using Flow Concentrator Channeling Device to Augmented Performance and Self-Starting Capability

Abstract

Water current turbine with vertical blade can be used on the river flow, ocean current or tidal current. The three parallel turbines with 40 degree azimuth different, have advantages doubling the power output and diminish the torque fluctuation. When the turbine equipped by the concentrator channeling device, the performance increased and the self-starting capability also augmented. During the experiments is indicated the flow phenomenon behind the turbine, the vortex formation created additional head or formation of low hydraulic level and facilitate the turbine coefficient of power produced greater than BETZ limit. The development of water current turbine at Fluid Machinery Laboratory FTMD ITB is starting with searching numerical simulation model at ANSYS 12.1 using NACA0018 blade profile comparing with experiment and carry out that the Reynolds Stress Model is adequate between simulation and the experiments. Further this model simulate variants of c/R (Chord Radius Ratio), TSR (Tip Speed Ratio), distance of shaft and configuration of the concentrator channeling device at the water flow velocity. Using NACA0018 blade profile as the best chose from the NACA0012, NACA0015, NACA0021 and NACA0024, Water current turbine equipped by the concentrator channeling device with c/R=0,32. The numerical simulation at the flow velocity of 0,4 m/s give CP =0,39 at TSR=3,2 but at the experiments measurement give CP =0,35 and TSR= 3,88. Other experimental case at flow velocity 0,6 m/s give CP =0,38 at TSR=2,18 the experiments and simulation result different is due to the friction loss of the transmission. The NACA0018 optimized by using MATLAB and XFOIL has better stall characteristic with angle of attack extend to 45 degree. Equipped by NACA0018 optimized, the three parallel current water turbine with concentrator channeling device numerical simulation at velocity V=0,4 m/s produce CP =0,64 at TSR=2,97 and at Velocity V=0,6 m/s produce CP =0,51 at TSR=3,35. Experiments results shown has CP= 0.64 greater than BETZ limit at the TSR= 2.97on the low flow velocity 0,4 m/s. In the operational is expected its turbine will operated at the higher flow velocity greater than 1,2 m/s to get better power density and the construction will smaller and lighter for unity of power. Keywords : Water Current Turbine, Channeling Device, Numerical Simulation, Experimental of Parallel Water Current Turbine, Blade Optimized