Computational modelling and experimental tank testing of the multi float WaveSub under regular wave forcing
A submerged wave device generates energy from the relative motion of floating bodies. In WaveSub, three floats are joined to a reactor; each connected to a spring and generator. Electricity generated damps the orbital movements of the floats. The forces are non-linear and each float interacts with the others. Tuning to the wave climate is achieved by changing the line lengths, so there is a need to understand the performance trade-offs for a large number of configurations. This requires an efficient, large displacement, multidirectional, multi-body numerical scheme. Results from a 1/25 scale wave basin experiment are described. Here, we show that a time domain linear potential flow formulation (Nemoh, WEC-Sim) can match the tank testing provided that suitably tuned drag coefficients are employed. Inviscid linear potential models can match some wave device experiments; however, additional viscous terms generally provide better accuracy. Scale experiments are also prone to mechanical friction, and we estimate friction terms to improve the correlation further. The resulting error in mean power between numerical and physical models is approximately 10%. Predicted device movement shows a good match. Overall, drag terms in time domain wave energy modelling will improve simulation accuracy in wave renewable energy device design. to understand the performance trade-offs for a large number of configurations. This requires an efficient, large displacement, multidirectional, multi-body numerical scheme. Results from a 1/25 scale wave basin experiment are described. Here, we show that a time domain linear potential flow formulation (Nemoh, WEC-Sim) can match the tank testing provided that suitably tuned drag coefficients are employed. Inviscid linear potential models can match some wave device experiments; however, additional viscous terms generally provide better accuracy. Scale experiments are also prone to mechanical friction, and we estimate friction terms to improve the correlation further. The resulting error in mean power between numerical and physical models is approximately 10%. Predicted device movement shows a good match. Overall, drag terms in time domain wave energy modelling will improve simulation accuracy in wave renewable energy device design.
- Research Organization:
- National Renewable Energy Laboratory (NREL), Golden, CO (United States)
- Sponsoring Organization:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE), Wind and Water Technologies Office (EE-4W)
- Grant/Contract Number:
- AC36-08GO28308
- OSTI ID:
- 1600898
- Alternate ID(s):
- OSTI ID: 1605722
- Report Number(s):
- NREL/JA-5000-75769; MainId:23208; UUID:df9c6279-dc30-ea11-9c2f-ac162d87dfe5; MainAdminID:11684
- Journal Information:
- Renewable Energy, Journal Name: Renewable Energy Vol. 152; ISSN 0960-1481
- Publisher:
- ElsevierCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Wave energy utilization: A review of the technologies
|
journal | April 2010 |
Factors Affecting The Measurement Of Axial Stiffness Of Polyester Deepwater Mooring Rope Under Sinusoidal Loading
|
conference | April 2013 |
Similar Records
Advanced Features and Recent Developments in the WEC-Sim Open-Source Design Tool: Preprint