Dynamic Loading on Tidal Turbine Arrays (DyLoTTA)

Transcription

1 SuperGen UK Centre for Marine Energy Research Annual Assembly 2018 Dynamic Loading on Tidal Turbine Arrays (DyLoTTA) UKCMER Tim O Doherty

2 Project Partners and Collaborators Academic Cardiff: Paul Prickett, Roger Grosvenor, Allan Mason-Jones, Carl Byrne Strathclyde: Cameron Johnstone, Joe Clarke Researchers: Matt Allmark, Stephanie Ordonez-Sanchez, Rodrigo Martinez, Cath Lloyd, Rob Ellis, Job Encarnacion, Song Fu Industrial Airborne Composites, ANSYS, Arup, Bosch Rexroth, Intertek, Lloyds Register, National Instruments, Nautricity Ltd, ORE Catapult, SKF, Tidal Energy Ltd. International Inha University South Korea [experimental/numerical] Mississippi State University USA [numerical] Dalhousie University Canada [Material] NREL USA [Material and blade design] UKCMER

3 Aims 1. Quantify the impact of wave-current interaction on the performance and integrity of TST devices when sited in an array. 2. Develop operational procedures to mitigate the impacts of extreme loading patterns. Specifically the dynamic loading patterns on the blade, blade root and eccentricity induced within the drive train. 3. Measure and mitigate such effects. Build 3 turbines to the same spec and test. Operate bench top rig with gear box. Use numerical tools to model turbine(s) under varying conditions of turbulence, waves and wakes CFD, BEMT, LCOE software.

4 Turbine Design 3 x Ø 0.9 m Turbines all to the same spec. Measures dynamic loads on 3 blades (flap and edge-wise), rotor thrust and torque, rotor position, rotational velocity, PMSM torque, stanchion loading and vibration through stanchion. Measurement Type Sample Rate Bladeroot bending moment (6 per turbine) Rotor Thrust Rotor Torque Stanchion Bending Moment 2 khz 2 khz 2 khz 2 khz Stanchion Vibration 10 khz

5 Blade Design Using the original Wortmann FX Chord length redistributed. Twist changed. Root modified for new turbines. New pitch angle Good agreement between Expt, CFD and Strathclyde BEMT code.

6 CP Average thrust range (N) INSEAN Waves and Control Strategies Testing undertaken at INSEAN in November Looking at the effects that two control strategies have on the loading and performance of a tidal turbine when subjected to regular and irregular waves Measure data: Rotor torque and thrust and blade root bending moment of 2 blades Torque control, tow Speed control, tow Torque control, Wreg Speed control, Wreg Torque control, Wirr Speed control, Wirr TSR Speed control, Wreg Speed contorl, Wirr Torque control, Wreg Torque control, Wirr Average rotor velocity (RPM) The control mode or the use of regular or irregular waves did not affect average values per test run. Thrust and torque fluctuations were substantial under both regular and irregular waves cases. Average peak loads 30% over the mean value under the conditions tested Torque control resulted in significantly larger thrust fluctuations per wave period than under speed control, for both regular and irregular waves.

7 Experimental Testing Time Table INSEAN: 2016 Initial turbine tested and calibration testing undertaken at different carriage velocities and wave cases IFREMER: 2018 Joint project with Welsh NRN and EPSRC IAA funding. Testing with grid generated turbulence with and without wake generated turbulence. No grid (TI = ~2%) with waves and current INHA University Blade design testing (on going) ACRE Rd: 2019 Detailed testing of three turbines for comparison FLOWAVE: turbine testing (+2 turbines with Southampton turbines (Myers, Allmark and Ordonez-Sanchez) IFREMER: 2019 Additional testing of wave and current conditions

8 Overview of IFREMER Testing: Testing undertaken at IFREMER in April Looking at the impact of both grid generated turbulence and wake flows on dynamic loading and performance of 1/20 th TST. Rotor torque and thrust, blade root bending moment on blade 2, rotational velocity, motor torque were recorded for 5 cases (Turbulence Intensity ~ 2 20 %): 1 background turbulence 2 grid generated turbulence cases with wake 2 grid generated turbulence no wake cases. Inlet velocity 1.1 m/s LDA measurements 1m upstream of turbine, in-line with nose cone centre

9 Overview of IFREMER Testing: Inlet velocity 1.1 m/s LDA measurements 1m upstream of turbine, in-line with nose cone centre

10 Overview of IFREMER Testing: Inlet velocity 1.1 m/s LDA measurements 1m upstream of turbine, in-line with nose cone centre

11 Wave models Stokes 2 nd Order + Deep water a Intermediate Water b Modelling with uniform and sheared velocity profiles, different wave characteristics.

12 Publications to date: JOURNALS Allmark, M., Grosvenor, R., & Prickett, P. (2017). An approach to the characterisation of the performance of a tidal stream turbine. Renewable Energy, 111, Allmark, M., Prickett, P., Grosvenor, R., & Frost, C. (2018). The specification of and testing of a Horizontal Axis Tidal Turbine Rotor Monitoring approach. PHM Society. International Journal of Prognostics and Health Management, 9(025), 9. Retrieved from S Ordonez-Sanchez, M Allmark, K Porter, R Ellis, C Lloyd, T O Doherty, C Johnstone. Analysis of a horizontal axis tidal turbine performance in the presence of regular and irregular waves using two control strategies. Submitted Journal of Marine Science Engineering Nov 2018 K Porter, S Ordonez-Sanchez, R E. Murray, M Allmark, C M. Johnstone, T O Doherty, D A. Doman, M J. Pegg. Flume Testing of Passively Adaptive Composite Tidal Turbine Blades under Combined Wave and Current Loading. Submitted Renewable Energy March S Ordonez-Sanchez, R Ellis, K Porter, M Allmark, T O Doherty, A Mason-Jones, C Johnstone. Numerical Models to Predict the Performance of Tidal Stream Turbines Working under Off-Design Conditions. Submitted to Ocean Engineering July 2018 S Salunkhe, S Bhushan, D Thompson, D. O Doherty and, T. O Doherty. Validation of hydrokinetic turbulent wake predictions and analysis of wake recovery mechanism. Submitted Renewable Energy June th EWTEC (2017) S Ordonez-Sanchez, K Porter, R Ellis, C Frost, M Allmark, T Nevalainen, T O Doherty, C Johnstone. Numerical Modelling Techniques to Predict Rotor Imbalance Problems in Tidal Stream Turbines. 12 th EWTEC, Cork, ISSN th AWTEC (2018) S Ordonez-Sanchez, K Porter, M Allmark, C Johnstone, T O Doherty. Blade Element Momentum Theory to Predict the Effect of Wave-Current Interactions on the Performance of Tidal Stream Turbines. 4th AWTEC, Taipei. K Porter, S Ordonez-Sanchez, M Allmark, T O Doherty, C Johnstone. Laboratory study of tidal turbine performance in irregular waves. 4th AWTEC, Taipei. M Allmark, K Porter, R Ellis, C Lloyd, T O Doherty, C Johnstone, C Byrne. The Development and Testing of a Lab-Scale Tidal Stream Turbine for the Study of Dynamic Device Loading. 4th AWTEC, Taipei. R Ellis, S Ordonez-Sanchez, A Mason-Jones, T O Doherty, C Johnstone. Design Process for a Scale Horizontal Axis Tidal Turbine Blade. 4th AWTEC, Taipei. C Lloyd, T O Doherty, A Mason-Jones. Development of wave-current numerical model using Linear and Stokes 2 nd Order Theory. 4th AWTEC, Taipei. S Fu, C Johnstone. A sea-state based investigation for performance of submerged tensioned mooring supported tidal turbines. 4th AWTEC, Taipei. AIAA FLUID DYNAMICS CONFERENCE (2018) J Bowman, S Bhushan, D S Thompson, D O'Doherty, T O'Doherty, A Mason-Jones A Physics-Based Actuator Disk Model for Hydrokinetic Turbines Fluid Dynamics Conference Atlanta, doi.org/ / th EWTEC (2019) - 9 ABSTRACTS SUBMITTED including 1 with NREL 3 with MSU 1 with Inha 1 with IFREMER

13 Acknowledgements EPSRC Impact Acceleration Account funding for IFREMER access ARCCA and Supercomputing Wales additional computing access Cardiff and Strathclyde Universities PhD funding NRN turbulence and wake data measurements MARINET 2 INSEAN access Supergen plus - access to FLOWAVE.

14 SuperGen UK Centre for Marine Energy Research Annual Assembly 2018 Dynamic Loading on Tidal Turbine Arrays (DyLoTTA) UKCMER Thank You