基于CFD数值计算方法对深水半潜式平台的涡激运动开展优化研究，提出一种能够抑制涡激运动的半潜平台新形式，并应用模型试验进行对比验证.研究了新型平台和传统型平台的涡激运动特征，对纵向偏移、横荡响应的幅值和分布规律，锁定区间等关键因素进行对比分析；研究了各方向耦合作用下平台的轨迹特征；详细分析了新型平台的减涡机制，从平台泄涡结构和涡激响应的均匀性、稳定性以及响应幅值等方面展开研究，阐述立柱的横剖面形状，排列形式等对平台涡激运动性能的影响.研究表明，这种“立柱的横剖面形状为梯形，呈外八字对称排列”的新型平台形式对抑制平台涡激运动具有积极影响，有助于减少或延缓强非线性涡激运动对系泊、立管系统的破坏作用.
Optimization study toward semi-submersible platform in deep water is investigated on the basis of computational fluid dynamics (CFD) numerical method. A new type of semi-submersible platform which can suppress vortex-induced motion (VIM) is presented. Model test is also carried out to testify the validity of the numerical method. The characteristics of VIM toward new and conventional platforms are studied respectively. Some key factors such as longitudinal offset, sway response, sway distribution tendency and lock-in interval are compared. The characteristics of platform motion trajectory coupled from each degree of freedom (DOF) are analyzed. Mechanism of vortex shedding suppression in new type of platform is investigated in detail. The effects of column cross section geometry and column arrangement on VIM performance of platform is studied from the uniformity, stability and amplitude of VIM response and the vortex shedding form. It indicates that this new configuration of platform where cross section geometry of each column is trapezoidal and the columns are arranged according to splayfooted type, plays a significant part in suppressing VIM, and contribute to decreasing and postponing the destructive effects toward mooring and riser system due to strong non-linear VIM.
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