半潜式钻井平台横撑截面形状的优化

海洋油气资源开发离不开半潜式钻井平台.因油田内短距离拖航需要,半潜式钻井平台可能遇到深吃水拖航工况,此时平台整体吃水较大,浮箱、部分立柱及横撑整体将位于水面以下并引起拖航阻力,其中横撑的阻力贡献占总阻力的25％左右.当横撑的长度及间距已经确定时,其拖航阻力主要受截面形状的影响.本文采用Fluent对一座实际平台的横撑拖航阻力进行研究,得到截面倒角对横撑阻力的影响规律,获得了截面倒角的最佳取值范围.结果表明,截面倒角半径大于0.3m时,横撑拖航阻力系数可以比不做倒角时减小60％以上,本文研究结果将为今后的半潜式钻井平台船型设计提供参考.

The shape optimization of the cross-section of the brace to a semi-submersible drilling platform

The semi submersible drilling platform plays an important role in the development of the deepwater oil resources.For the demand of the short distance translocation in an oil field,the deep draught towing maybe encountered.Under this condition,the whole pontoons and the braces,part of the cylinders submerged in the water which caused towage resistance,the resistance of the braces toke part of 25% of the whole resistance.When the design plan was finalized,the main dimension and the distance of the braces were fixed,the towage resistance mainly caused by the shape of the cross section.Thus the software Fluent was used here to compute the drag resistance of a brace in a uniform viscous flow with different fillet radius,the regulation on the changes to the resistance was analyzed,also the a rational range of the fillet radius was got.According to the computation,the drag resistance coefficient of the brace with a fillet radius more than 0.3m will be reduced more than 60%.The research results may provide good proposal to the design of a new platform.