Stability based approach to design cold-water pipe (CWP) for ocean thermal energy conversion (OTEC)

Journal Article

Title: Stability based approach to design cold-water pipe (CWP) for ocean thermal energy conversion (OTEC)

Author:

Adiputra, R.; Utsunomiya, T.

Publication Date:

November 1, 2019

Journal:

Applied Ocean Research

Volume:

Pages:

101921

Publisher:

Elsevier

Affiliation:

Kyushu University

Technology:

OTEC, Open-Cycle

Collection Method:

Modeling

Engineering:

Materials, Structural

Language:

English

Document Access

Website:

External Link

Attachment:

Access File

Notice: This material may be protected by Copyright Law.

Citation

Adiputra, R.; Utsunomiya, T. (2019). Stability based approach to design cold-water pipe (CWP) for ocean thermal energy conversion (OTEC). Applied Ocean Research , 92, 101921. https://doi.org/10.1016/j.apor.2019.101921

@article{Adiputra-2019-3558,
author = {Adiputra, R and Utsunomiya, T},
title = {Stability based approach to design cold-water pipe (CWP) for ocean thermal energy conversion (OTEC)},
journal = {Applied Ocean Research },
year = {2019},
month = {nov},
publisher = {Elsevier},
volume = {92},
pages = {101921},
doi = {10.1016/j.apor.2019.101921},
url = {https://www.sciencedirect.com/science/article/pii/S0141118719303062},
keywords = {OTEC, Open-Cycle, Modeling, Materials, Structural},
}

Export Citation to BibTex

TY - JOUR
TI - Stability based approach to design cold-water pipe (CWP) for ocean thermal energy conversion (OTEC)
AU - Adiputra, R
AU - Utsunomiya, T
T2 - Applied Ocean Research
AB - Cold-water pipe (CWP) is a novel, most-challenging component of Ocean Thermal Energy Conversion (OTEC) floating structure which is installed to transport the deep seawater to the board. For commercial scale, the transported seawater flow rate will be in the order of 102 m3/s. This large amount of internal flow may trigger instability which leads to the failure of CWP. Considering this issue, the present paper aims to design commercial-scale OTEC CWP focusing on the effects of internal flow to the stability of the pipe. The design analysis is deliberated to select the pipe material, top joint configuration (fixed, flexible, pinned) and bottom supporting system (with and without clump weight). Initially, the analytical solution is built by taking into account the components of the pipe dynamics. Separately, a fully coupled fluid-structure interaction analysis between the pipe and the ambient fluid is carried out using ANSYS interface. Using scale models, the results obtained from the analytical solution are compared with the ones from numerical analysis to examine the feasibility of the analytical solution. After being verified, the analytical solution is used to observe the dynamic behavior of the CWP for 100 MW-net OTEC power plant in the full-scale model. The results yield conclusions that pinned connection at the top joint is preferable to decrease the applied stress, clump weight installation is necessary to reduce the motion displacement and Fiber Reinforced Plastic (FRP) is the most suitable material among the examined materials.
DA - 2019/11//
PY - 2019
PB - Elsevier
VL - 92
SP - 101921
UR - https://www.sciencedirect.com/science/article/pii/S0141118719303062
DO - 10.1016/j.apor.2019.101921
LA - English
KW - OTEC
KW - Open-Cycle
KW - Modeling
KW - Materials
KW - Structural
ER -

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Abstract

Cold-water pipe (CWP) is a novel, most-challenging component of Ocean Thermal Energy Conversion (OTEC) floating structure which is installed to transport the deep seawater to the board. For commercial scale, the transported seawater flow rate will be in the order of 10² m³/s. This large amount of internal flow may trigger instability which leads to the failure of CWP. Considering this issue, the present paper aims to design commercial-scale OTEC CWP focusing on the effects of internal flow to the stability of the pipe. The design analysis is deliberated to select the pipe material, top joint configuration (fixed, flexible, pinned) and bottom supporting system (with and without clump weight). Initially, the analytical solution is built by taking into account the components of the pipe dynamics. Separately, a fully coupled fluid-structure interaction analysis between the pipe and the ambient fluid is carried out using ANSYS interface. Using scale models, the results obtained from the analytical solution are compared with the ones from numerical analysis to examine the feasibility of the analytical solution. After being verified, the analytical solution is used to observe the dynamic behavior of the CWP for 100 MW-net OTEC power plant in the full-scale model. The results yield conclusions that pinned connection at the top joint is preferable to decrease the applied stress, clump weight installation is necessary to reduce the motion displacement and Fiber Reinforced Plastic (FRP) is the most suitable material among the examined materials.