在单独恒定流条件下,以某一海上风电大直径单桩基础为研究对象,提出一种扰流板防冲刷结构,建立三维数值模型。基于数值模拟,研究扰流板结构对桩基础周围局部冲刷的影响机制,探讨扰流板长度L和高度H2对局部马蹄涡位置和强度的影响,分析床面剪切应力受扰流板几何的影响规律。研究发现,扰流板结构能有效地减弱局部马蹄涡强度和减小桩周海床床面剪切应力;局部马蹄涡受扰流板几何的影响呈现3种流动机制;当L/H2=1时,扰流板具有较好的冲刷防护特性。总的来说,扰流板防冲刷结构对单桩基础局部冲刷具有较好的防护效果。
Abstract
Monopile foundations have become the most common infrastructure in the field of offshore wind power due to their simple structure and convenient construction. However, they are often accompanied by local erosion of the seabed around the pile. In this study, a spoiler anti-erosion structure is proposed, and a three-dimensional numerical model is established using a large-diameter monopile foundation of offshore wind power as the research object. Based on numerical simulations, the influence of the spoiler structure on local scouring around the pile is studied under constant currents. The influence of the spoiler’s length （L） and height （H2） on the position and strength of local horseshoe vortices is discussed, and the effect of local bed shear stress is also analyzed. Results show that the spoiler structure can effectively weaken the strength of local horseshoe vortices, reduce shear stress on the bed around the monopile. The local horseshoe vortex exhibits three flow mechanisms under the influence of the spoiler’s geometry. When L/H2=1, the spoiler has better erosion protection characteristics. Overall, the spoiler structure has a good protective effect on local erosion protection and is significant for guiding the protection design of pile foundations.
关键词
海上风电 /
单桩 /
圆柱绕流 /
冲刷 /
马蹄涡 /
床面剪应力
Key words
offshore wind power /
monopile /
cylinder flow /
scouring /
horseshoe vortex /
bed surface shear stress
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基金
中国华能集团有限公司科技项目（HNKJ20-H54）; 华能清能院研究与开发基金项目（QNYJJ22-12）
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