As one of the key safety problems, the motion performance and touching sea bottom of a FPSO are paid much attention by the ocean oil companies when the FPSO is exposed to survival storms in the shallow-water working a...As one of the key safety problems, the motion performance and touching sea bottom of a FPSO are paid much attention by the ocean oil companies when the FPSO is exposed to survival storms in the shallow-water working areas. In this paper, time-domain numerical simulations are carried out on a 160 kDWT FPSO with a Yoke mooring system moored in the BZ25-1 oilfield with a water depth of 16.7m. The results are compared with those of the corresponding model tests. Good agreement shows that the time-domain simulations can be used to predict the performance of the FPSO in shallow-water reasonably. It is found that the touch of seabed by a fully loaded FPSO occurred few times under survival storm conditions. Therefore, the FPSO should be less loaded than that in the fully loaded condition under the survival storms.展开更多
The present research deals with the numerical prediction of the air gap within the 6th generation of deepwater drilling floating semi-submersible platform and the experimental studies on the slamming loadings onto the...The present research deals with the numerical prediction of the air gap within the 6th generation of deepwater drilling floating semi-submersible platform and the experimental studies on the slamming loadings onto the structure. The survivability of the floating model with a mooring system was tested under extreme wave of 10-year return period. In the numerical simulation of the Gaussian method,the narrow band model was applied to obtain the first-order wave surface equation and the modified second-order wave surface equation. The hydrodynamic responses of the floating body,i.e. radiation damping,added mass,second-order wave excitation force and drifting force,were computed by using the potential flow theory based on higher order boundary element method in frequent domain. In the experimental analysis,high-frequency sensors were installed at the lower deck to measure the wave slamming loads. Equivalent truncated mooring system was applied to make sure position of the floating body in the wave tank. The comparison between the numerical and experimental results showed the numerical model underestimated the air gap of the floating body. Nevertheless,the predictions of the high risk spots underneath the floating deck that is prone to wave slamming obtained from both models were agreeable to each other. The experimental results also revealed that the wave slamming events often occurred at the connection point between the rear columns and the lower deck.展开更多
基金supported by the Development Program of China(863 Program,No.2002AA602011)
文摘As one of the key safety problems, the motion performance and touching sea bottom of a FPSO are paid much attention by the ocean oil companies when the FPSO is exposed to survival storms in the shallow-water working areas. In this paper, time-domain numerical simulations are carried out on a 160 kDWT FPSO with a Yoke mooring system moored in the BZ25-1 oilfield with a water depth of 16.7m. The results are compared with those of the corresponding model tests. Good agreement shows that the time-domain simulations can be used to predict the performance of the FPSO in shallow-water reasonably. It is found that the touch of seabed by a fully loaded FPSO occurred few times under survival storm conditions. Therefore, the FPSO should be less loaded than that in the fully loaded condition under the survival storms.
文摘The present research deals with the numerical prediction of the air gap within the 6th generation of deepwater drilling floating semi-submersible platform and the experimental studies on the slamming loadings onto the structure. The survivability of the floating model with a mooring system was tested under extreme wave of 10-year return period. In the numerical simulation of the Gaussian method,the narrow band model was applied to obtain the first-order wave surface equation and the modified second-order wave surface equation. The hydrodynamic responses of the floating body,i.e. radiation damping,added mass,second-order wave excitation force and drifting force,were computed by using the potential flow theory based on higher order boundary element method in frequent domain. In the experimental analysis,high-frequency sensors were installed at the lower deck to measure the wave slamming loads. Equivalent truncated mooring system was applied to make sure position of the floating body in the wave tank. The comparison between the numerical and experimental results showed the numerical model underestimated the air gap of the floating body. Nevertheless,the predictions of the high risk spots underneath the floating deck that is prone to wave slamming obtained from both models were agreeable to each other. The experimental results also revealed that the wave slamming events often occurred at the connection point between the rear columns and the lower deck.
