Structural Safety Analysis for an Oscillating Water Column Wave Power Conversion System Installed in Caisson Structure
1.1. Development of an Oscillating Water Column (OWC) Wave Energy Converter
1.2. Objectives of the Study
2. Analytical Model and Environmental Forces
2.1. Analytical Model of the Structure
2.2. Environmental Forces
3. Mechanic Analysis of Structural Safety
3.1. Global Structural Analysis
3.2. Structural Analysis for the Chamber of OWC Converter
3.2.1. Transverse Deformation for the front Curtain-Wall
3.2.2. Transverse Deformation for the Top Ceiling-Slab
3.2.3. Transverse Deformation for the Side-Wall
3.2.4. Discussions on the Deformation of Chamber Members
4. Evaluation of Air-pressure in the Chamber during the Operation of Wave Energy Conversion
4.1. Theorem of Fluid Mechanics Applied in the Study
4.2. Analysis of Wave-Induced Air Pressure in the Chamber
- According to the analysis for the structural safety of this study, for the whole structural safety that included both the caisson breakwater and attached OWC system, the deformations induced from the design-wave, which was based on a storm-wave of 50-year return period, was under the capacity of the concrete material.
- The second part analysis of the structural safety, particularly focused on the air-chamber of the OWC converter, where the maximum deformation occurred transversely at the ceiling-slab of the air-chamber for the OWC converter, whereas the front curtain wall subjected to wave-impact directly would also deform greatly, but not so significantly. The developed strains for both the ceiling-slab and the front curtain-wall were well over the strain limit for a concrete material and therefore, when the chamber structure was subjected to a wave close to the designed storm-wave as utilized in the analysis, a major damage may occur on both the ceiling-slab and the front curtain-wall.
- According to the study of the air-pressure induced by the heave motion of the waves in the chamber, the pressure was small and would not significantly influence the structural safety of the OWC chamber attached to a caisson structure.
- It is concluded that when the OWC is attached to a traditional breakwater structure, the location will be an important factor to decide the performance of energy converting efficiency. To design an OWC structure that may sustain a storm wave of 50-year return period could be expensive. In terms of economic consideration, as long as the damage of the associated structure would not affect the structural safety and operation of the main structure, a design-wave based on a storm of shorter return period should be considered.
Conflicts of Interest
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Lee, H.H.; Wu, T.-Y.; Lin, C.-Y.; Chiu, Y.-F. Structural Safety Analysis for an Oscillating Water Column Wave Power Conversion System Installed in Caisson Structure. J. Mar. Sci. Eng. 2020, 8, 506. https://doi.org/10.3390/jmse8070506
Lee HH, Wu T-Y, Lin C-Y, Chiu Y-F. Structural Safety Analysis for an Oscillating Water Column Wave Power Conversion System Installed in Caisson Structure. Journal of Marine Science and Engineering. 2020; 8(7):506. https://doi.org/10.3390/jmse8070506Chicago/Turabian Style
Lee, Hsien Hua, Thung-Yeh Wu, Chung-You Lin, and Yung-Fang Chiu. 2020. "Structural Safety Analysis for an Oscillating Water Column Wave Power Conversion System Installed in Caisson Structure" Journal of Marine Science and Engineering 8, no. 7: 506. https://doi.org/10.3390/jmse8070506