Numerical Simulation of an Experimental Ocean Current Turbine

2013 ◽  
Vol 38 (1) ◽  
pp. 131-143 ◽  
Author(s):  
James H. VanZwieten ◽  
Nicolas Vanrietvelde ◽  
Basil L. Hacker
Keyword(s):  
Numerical Simulation ◽  
Ocean Current ◽  
Current Turbine

scholarly journals Modeling and Numerical Simulation of a Buoyancy Controlled Ocean Current Turbine

2021 ◽  
Vol 4 (2) ◽  
pp. 47-58
Author(s):  
Arezoo Hasankhani ◽  
James VanZwieten ◽  
Yufei Tang ◽  
Broc Dunlap ◽  
Alexandra De Luera ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
High Energy ◽  
Ocean Currents ◽  
High Energy Density ◽  
Ocean Current ◽  
Fault Models ◽  
Near Surface ◽  
Renewable Power ◽  
Flow Speeds ◽  
Current Turbine

Increased global renewable power demands and the high energy density of ocean currents have motivated the development of ocean current turbines (OCTs). These compliantly mooring systems will maintain desired near-surface operating depths using variable buoyancy, lifting surface, sub-sea winches, and/or surface buoys. This paper presents a complete numerical simulation of a 700 kW variable buoyancy controlled OCT that includes detailed turbine system, inflow, actuator (i.e., generator and variable buoyancy), sensor, and fault models. Simulation predictions of OCT performance are made for normal, hurricane, and fault scenarios. Results suggest this OCT can operate between depths of 38 m to 329 m for all homogeneous flow speeds between 1.0-2.5 m/s. Fault scenarios show that rotor braking results in a rapid vertical OCT system assent and that blade pitch faults create power fluctuations apparent in the frequency domain. Finally, simulated OCT operations in measured ocean currents (i.e., normal and hurricane conditions) quantify power statistics and system behavior typical and extreme conditions.

Numerical Analysis of Hydrodynamic Performance of FX-83-W Hydrofoil Current Turbine

2017 ◽  
Author(s):  
Yuchen Shang ◽  
Nikolaos I. Xiros
Keyword(s):  
Numerical Simulation ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Open Water ◽  
Hydrodynamic Performance ◽  
Ocean Current ◽  
Thrust Coefficient ◽  
Cfd Method ◽  
Three Dimensional Coordinate ◽  
Current Turbine

Ocean current flow characteristics are relatively stable and predictable, current turbine absorbs the energy of the ocean currents by the blades with a relative stable and lower angular velocity which indicates the capacity of current turbine greater than the onshore wind turbine. In this paper, the CFD method is utilized to calculate and analyze the working principle of FX-83-W current turbine. The three-dimensional coordinate of FX-83-W Hydrofoil blade surface have been calculated by MATLAB code, and 3D model has been established in Gambit. The basic control equations of CFD and its numerical solution are described, Reynolds Averaged N-S equations is used, and the realizable k-e turbulence model is introduced to solve the Reynolds stress in the RANS equation. The numerical algorithm is the finite volume method (FVM), and the numerical simulation of CFD is used to study the open water performance, leading to thrust coefficient KT and torque coefficient KQ of FX-83-W Hydrofoil. The hydrodynamic thrust and hydrodynamic power of the ocean current turbine under different sea conditions have been obtained by numerical simulation.

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

2015 ◽  
Vol 758 ◽  
pp. 153-158
Author(s):  
Priyono Sutikno ◽  
Yuliandra Syahrial Nurdin ◽  
Doddy Risqi ◽  
Eki Mardani ◽  
Erpinus Sihombing
Keyword(s):  
Numerical Simulation ◽  
Flow Velocity ◽  
River Flow ◽  
Low Flow ◽  
Ocean Current ◽  
Water Current ◽  
Speed Ratio ◽  
Blade Profile ◽  
Water Flow Velocity ◽  
Current Turbine

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

Advances in ocean current turbine blade design

2021 ◽  
Author(s):  
Hassan Mahfuz ◽  
Nicholas Asseff ◽  
Mohammad Wasim Akram ◽  
Fang Zhou ◽  
Takuya Suzuki ◽  
...  
Keyword(s):  
Turbine Blade ◽  
Ocean Current ◽  
Blade Design ◽  
Turbine Blade Design ◽  
Current Turbine

Design and Analysis of a Marine Current Turbine

2017 ◽  
Author(s):  
T. Karthikeyan ◽  
E. J. Avital ◽  
N. Venkatesan ◽  
A. Samad
Keyword(s):  
Pitch Angle ◽  
Flow Simulation ◽  
Ocean Current ◽  
Power Coefficient ◽  
Design Parameters ◽  
Marine Current Turbine ◽  
Commercial Code ◽  
Marine Current ◽  
Current Turbine ◽  
Blade Pitch Angle

Ocean stores a huge amount of energy and ocean current energy can be a viable source in future. In this article, an axial marine current turbine has been optimized to enhance its power coefficient through numerical modeling. The blade pitch-angle and number of blades are the design parameters chosen for the analysis to find the optimal design. A commercial code for CFD simulations with in-house optimization code was used for the analysis. It was found that, changing the blade pitch-angle and reducing the number of blades can improve the turbine’s coefficient of power. This is due to increase in lift and reduction of losses caused by turbulence near the downstream of the turbine. The article presents flow-simulation difficulties and characteristic curves to identify the differences between the actual and optimized turbine. The detailed flow physics is discussed and pictured in the post processed plots.

scholarly journals A Comparative Study on the Performance of a Horizontal Axis Ocean Current Turbine Considering Deflector and Operating Depths

2020 ◽  
Vol 12 (8) ◽  
pp. 3333
Author(s):  
Nauman Riyaz Maldar ◽  
Cheng Yee Ng ◽  
Lee Woen Ean ◽  
Elif Oguz ◽  
Ahmad Fitriadhy ◽  
...  
Keyword(s):  
Fluid Pressure ◽  
Three Dimensional ◽  
Horizontal Axis ◽  
Ocean Current ◽  
Power Coefficient ◽  
Cfd Simulations ◽  
Torque Coefficient ◽  
Computational Fluid Dynamics Cfd ◽  
Turbine Design ◽  
Current Turbine

Several different designs and prototypes of ocean current turbines have been tested over recent years. For every design test, emphasis is given to achieving an optimum power output from the flow. In this study, the performance of a Horizontal Axis Ocean Current Turbine (HAOCT) has been investigated using three-dimensional Computational Fluid Dynamics (CFD) simulations for three cases, namely, (1) a turbine without a deflector, (2) a turbine with a deflector, and (3) a turbine with a deflector operating at a higher fluid depth. The turbine design was modeled in DesignModeler software and simulations were carried out in commercial CFD software Flow-3D. The Torque Coefficient (Cm) and Power Coefficient (Cp) for the turbine have been investigated for a certain range of Tip-Speed Ratios (TSRs) in a flow velocity of 0.7 m/s. Furthermore, comparisons have been made to demonstrate the effect of the deflector on the performance of the turbine and the influence of a higher fluid pressure on the same. The results from the simulations indicate that the higher value of Cp was achieved for Case 2 as compared to the other two cases. The findings from the study indicate that the use of the deflector enhances the performance of the turbine. Furthermore, a higher fluid pressure acting on the turbine has a significant effect on its performance.

Sign in / Sign up

Export Citation Format

Share Document