Performance And Construction&Installation Analysis Of Semi-submersible Test Platform

Energy is an important resource for the progress and development of human beings. With the continuous exploitation of deep sea oil and gas resources, more and more attentions have been paid to the related platform technology. Semi-submersible platform has been widely used because of its advantages, such as large variable load, strong wind resistance、adaptation to a wide range of water depth and etc. So it is of important significance to do the comprehensive analysis of hydrodynamic performance of the semi-submersible platform and its mooring system, as well as the research of the platform structural strength. The results can provide a reference for the design optimization of the platform.This paper selects a small semi-submersible test platform for study, and its hydrodynamic performance and structural strength were analyzed. The main work includes the following aspects:(1) Semi-submersible test platform detailsAs the first small semi-submersible platform only for scientific experiments, this paper made a detailed presentation for its overall design, the basic layout and engineering environment;(2) Analysis of hydrodynamic performance of the semi-submersible test platform and its mooring systemAccording to the three-dimensional potential flow theory, hydrodynamic performance of the semi-submersible test platform and its mooring system are comprehensively analyzed by using of the ANSYS-AQWA software in this paper. The response amplitude operator (RAO) of motions in various frequency and wave directions is calculated first on frequency domain. Thus, a database of frequency domain hydrodynamic parameters is built up. Then the time domain coupled numerical simulation of the test platform and its mooring system are carried out in both operating and survival sea conditions, in order to obtain the motion responses in six degree of freedom and the tensions of mooring system, as well as the anchor situation.Meanwhile, sensitivity analyses of various parameters in the test platform are conducted. The platform motion response variations are explored by changing the center of gravity height of the platform in this paper.(3) Overall finite element strength analysis of the platformUsing ANSYS finite element analysis module to build the whole model of the test platform, and its overall structural strength are analyzed in a variety of conditions. The weak part of the platform is given to verify the structural design safety and the reasonableness of the platform.(4) Platform construction technology researchThe process of platform construction and installation are introduced, which can provide a practical engineering experience to the related engineering personnel and college students.This paper focuses on the first semi-submersible test platform in our country and analyses the hydrodynamic performance of the platform and its mooring system, as well as the structural strength. Besides, the whole construction and anchoring process of the platform is introduced. The results of this paper will be very significant to the technical development and design optimization of semi-submersible platform, and provide a practical experience to the related personnel.