Method for analyzing response of steel catenary riser to waves

Abstract

The invention belongs to a technique for researching a steel catenary riser of a deep-sea oil and gas platform and particularly relates to a method for analyzing the response of a steel catenary riser to waves. In the method, a model of an elastic ground beam is used to simulate a streamline section of the steel catenary riser and the simulative models of the overhung section and the streamline section of the steel catenary riser are combined with the equation of motion of a floating platform to built an integrated motion analysis model of the steel catenary riser and the floating platform, the equation of the integrated motion analysis model is solved to obtain the response of the steel catenary riser to waves, and at the same time, a model of the suction of sea bed soil is built according to the influence of the suction of the sea bed soil to the steel catenary riser and is used in the analysis of the response of the steel catenary riser to waves. The method can improve the accuracyof the calculation of the steel catenary riser and makes the analysis of the steel catenary riser closer to the actual situation of a project.

Description

technical field [0001] The invention belongs to the research technology of steel catenary risers of deep-sea oil and gas platforms, and in particular relates to a wave response analysis method of deep-sea steel catenary risers. Background technique [0002] The steel catenary riser is a new riser system for deep-sea oil and gas development. The first steel catenary riser was officially used in the development of deep-sea oil and gas resources in 1996. It is technically and economically superior to the traditional flexible riser and top tension The riser system has made great progress and has become the preferred riser system for the development of deep sea oil and gas resources. [0003] Compared with flexible risers, the cost of steel catenary risers is low; compared with top-tensioned risers, it does not require compensation for top tension and heave motion of floating bodies, and is considered to be an effective cost-reducing stand for deep-sea oil and gas resource develo...

AI Technical Summary

Problems solved by technology

The current analysis methods all use spring supports at the nodes (the lumped mass model can only act on the lumped mass) to simulate the continuous distribution of seabed soil constraint reaction force, therefore, it is a simplified analysis method, and its results are not accurate enough

[0016] It can be seen that the existing analysis methods for steel catenary risers do not consider the influence of the large deflection of the steel catenary riser on the stiffness of the riser, and do not consider the dynamic coupling between the floating platform and the steel catenary riser The effect of the seabed soil suction on the streamline section of the steel catenary riser is not considered, and the continuously distributed seabed soil constraint force is simplified as a concentrated constraint reaction force, and the continuous distributed mass system is simplified as a concentrated mass system

Therefore, the accuracy of the analysis results obtained is not high enough, and there is a certain gap with the actual situation of the project.

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