TY - GEN
T1 - DYNAMICS of A COLD WATER INTAKING PIPE SUBJECT to INTERNAL FLOW and MOTION EXCITATION
AU - Hisamatsu, Ryoya
AU - Utsunomiya, Tomoaki
N1 - Publisher Copyright:
© 2023 American Society of Mechanical Engineers (ASME). All rights reserved.
PY - 2023
Y1 - 2023
N2 - A cold water intaking pipe/riser is an important component of a floating Ocean Thermal Energy Conversion (OTEC) plant. Its dynamics subject to the large intake flow rate of seawater and motion excitation from a platform have not been definitively understood. This study experimentally investigates the dynamics with two experimental setups. The first setup uses a controllable pump and 4 m long pipe to investigate instability. The second setup uses a high capacity pump to investigate instability and forced vibration subject to top harmonic excitation. The results are compared with an analytical model considering the inlet flow effect. The analytical model predicts that a water intake pipe does not lose stability at any high flow velocity. The experiment newly confirmed that the pipe keeps stable up to 5.5 m/s which is the maximum velocity attainable in this experiment. The experiment and analytical model also highlight that a high internal flow velocity significantly increases the amplitude of inline vibration. Furthermore, the experiment also takes a new look on the dynamics such as long-period vibration and transverse vibration.
AB - A cold water intaking pipe/riser is an important component of a floating Ocean Thermal Energy Conversion (OTEC) plant. Its dynamics subject to the large intake flow rate of seawater and motion excitation from a platform have not been definitively understood. This study experimentally investigates the dynamics with two experimental setups. The first setup uses a controllable pump and 4 m long pipe to investigate instability. The second setup uses a high capacity pump to investigate instability and forced vibration subject to top harmonic excitation. The results are compared with an analytical model considering the inlet flow effect. The analytical model predicts that a water intake pipe does not lose stability at any high flow velocity. The experiment newly confirmed that the pipe keeps stable up to 5.5 m/s which is the maximum velocity attainable in this experiment. The experiment and analytical model also highlight that a high internal flow velocity significantly increases the amplitude of inline vibration. Furthermore, the experiment also takes a new look on the dynamics such as long-period vibration and transverse vibration.
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U2 - 10.1115/OMAE2023-103375
DO - 10.1115/OMAE2023-103375
M3 - Conference contribution
AN - SCOPUS:85173904817
T3 - Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE
BT - Ocean Space Utilization
PB - American Society of Mechanical Engineers (ASME)
T2 - ASME 2023 42nd International Conference on Ocean, Offshore and Arctic Engineering, OMAE 2023
Y2 - 11 June 2023 through 16 June 2023
ER -