重心高度对浮式结构水动力性能的影响

Impact of the Height of Gravity Center to Hydrodynamic Performance of Floating Structure

通常在计算模拟海上浮式风机平台运动时,外部结构形式是影响水动力性能的主要因素,而重心在水动力计算中的影响则被忽略。为了研究重心变化对结构物水动力响应的影响,以5MW浮式风机平台作为研究对象,通过数值模拟的方法,分别对浮筒间距、撑杆形式以及有无垂荡板与重心高度变化结合加以分析研究。结果表明：改变浮筒间距时,重心高度对水动力性能的影响主要体现在横、纵摇及横、纵荡方面,且浮筒间距较大的基础形式达到峰值响应时的重心更低;斜撑的改变与其随重心变动得到的运动幅值规律一致,且峰值响应之后的各响应幅值在数值上基本相同;垂荡板的添加有效降低了纵摇及垂荡幅值;对于三浮筒半潜式平台,最佳重心位置为水下3~8m处。

In general, the external structures are the main factors influencing the hydrodynamic performance in the computation simulation, however, the impact of gravity center on the hydrodynamic calculation is ignored. In order to study the effect of gravity center change on the structure hydrodynamic response, a 5MW floating wind power turbine system is taken as the research object. By means of numerical simulation method, the relationship between the height change of gravity center and float spacing, bar form as well as heave plate, respectively is studied. The results show that when the float distance changing, the effect of gravity center height on hydrodynamic performance is mainly reflected in the cross, longitudinal and transverse, longitudinal swing, and when the basic form of larger float distance reaches at the peak response, the gravity center is even lower; the change of diagonal brace is consistent with the rule of motion amplitude along with gravity center changing, and each response amplitude after peak response in terms of numerical value is basically the same; the heave plate adding is able to effectively reduce the pitching and heaving amplitude; for the three floating semi-submersible platform, the best central location is located at the underwater of 3—8m.