风、浪、流联合作用下钻井船漂移载荷时域模拟

基于定位考虑对带月池的深水作业钻井船的漂移载荷进行了时域模拟分析。采用API风谱描述不规则风场,基于风生浪因素设置分析的环境参数,基于OCIMF计算风载荷和流载荷;利用势流理论和Newman假设计算二阶波浪漂移力载荷,提取得到数值结果并进行处理,得到不同方向、不同环境条件下各项漂移力的统计值和统计特征。结果表明:在时域内对深水作业钻井船漂移载荷进行分析,更加具有真实性,波浪、风、流引起的漂移载荷依次减小,且均随环境条件的增大而快速增加;在风向、流向和浪向不同时,使得船首处于迎浪状态对钻井船的定位有利;优化船体外型是降低钻井船漂移载荷的有效手段。

Time domain simulation for drift loads of drilling ship

Time domain simulation for drift loads of a deep-water drilling ship with a moonpool is analyzed considering the positioning.The irregular wind field is described by API wind spectrum,and the environmental parameters are set by considering the factors of wind and wave.The wind load and currents load are calculated by OCIMF based on empirical formula,and the second-order wave drift loads are calculated and analyzed by potential theory and Newman hypothesis.The numerical results are extracted and processed,and the statistical values of drift loads in different directions and under different environmental conditions are obtained,and the statistical characteristics of drift loads are analyzed.The results show that the analysis of drift loads of deepwater drilling vessels in time domain is more realistic.The drift loads caused by waves,winds and currents decrease in turn and increase rapidly with the increase of environmental conditions.When the directions ofwind,flow and wave are different,it is beneficial to the positioning of drilling vessel when the bow is in head sea.Optimizing hull shape is an effective way to reduce the drift load of drilling ship.