【作者】 季顺迎；

【导师】 程耿东； 岳前进；

【作者基本信息】 大连理工大学 ， 工程力学， 2001， 博士

【摘要】 在渤海油气开发中，海冰是影响冰区结构设计、钻采施工、生产作业的重要海洋环境条件。对渤海海冰进行数值模拟和预测，并与油气开发工程紧密结合是合理确定海冰设计参数，减少冰害损失的有效途径。 本文结合国家自然科学基金委和中海石油渤海公司联合资助的“九五”重点基金项目中的“渤海海冰数值模拟及其工程应用”子课题，根据辽东湾海冰现场观测资料，对渤海海冰数学模型中的计算参数进行了确定，分析了渤海海冰的热力和动力要素特点，并在海冰数值模拟和预测的基础上对辽东湾JZ20-2海域MUQ锥体平台的冰激结构振动进行了分析。 渤海海冰数值模拟和预测主要是借鉴极区及其冰缘区的大、中尺度数学模型。为此，本文通过对极区海冰数值模拟及其相关研究的系统总结，并考虑渤海海冰的特点，详细分析了两种不同的海冰数值计算方法，即欧拉坐标下的差分法和拉格朗日坐标下的光滑质点法。 为使渤海海冰的数学模型能够适应渤海冰情特点，并对其中的重要计算参数进行确定，作者在辽东湾JZ20-2海域进行了连续7个冬季的海冰现场观测，完成了多次破冰船海冰和沿岸冰的调查工作，获得了大量的海冰观测资料。在此基础上，本文分析了冰面太阳辐射的计算方法及其在整个冰期内的变化特征，讨论了太阳辐射对冰面其它热力因素和海冰生消的影响；利用剩余法计算了海洋热通量在整个冰期内的变化趋势，讨论了气象和水文条件、海冰厚度等因素对海洋热通量的影响；归纳了计算海冰拖曳系数的涡动法、剖面法和动量法，并利用动量法对低密集度平整海冰的拖曳系数进行了初步计算。 在海冰生消的热力要素分析中，本文对冰面太阳辐射、长波辐射、感热、潜热、冰内传导热和冰下海洋热通量等热力要素的变化规律进行了研究。针对渤海海冰热力要素变化特点，并根据海冰生消机理和海冰数值模拟结果，提出了渤海海冰特征厚度的概念，并计算了不同气温、风速、相对湿度和海洋热通量等条件下的特征冰厚。在海冰漂移的动力要素分析中，本文对海冰的风和流拖曳力、海冰内力、科氏力和海面倾斜力等动力要素进行了讨论和对比。针对渤海海冰动力特点，并参考实测冰脊资料，分析了压力冰脊的几 AbstraCt何特征，建立了冰脊帆高的力学模型，并给出了渤海不同冰区在不同重现期的冰脊设计参数。 对于辽东湾全场海冰分布，采用欧拉坐标系下的有限差分法进行了数值模拟，而对于区域性漂移海冰的数值模拟采用的则是拉格朗日坐标系下的光滑质点法：在对辽东湾区域性漂移海冰和全场海冰数值模拟中，充分考虑了渤海潮汐的影响，并对模拟的冰厚、密集度、冰速和冰内应力状态等海冰参量进行了动态数字图象处理。 冰激结构振动给渤海冰期油气结构和生产作业系统的安全运行带来很大威胁。为此，本文将海冰数值预测、海冰物理力学参数推算和冰激结构振动分析相结合，开发了渤海海冰数值模拟及其工程应用程序系统。它可为渤海冰期油气开发中的安全生产作业提供冰激结构振动信息，是海冰管理的重要组成部分。更多还原

【Abstract】 In the oibas exploitation of Bohai Sea, sea ice is an important marine environmental condition, which affects the offshore structure design, field construction and production safety. Considering the engineering requirements in oillgas development, the sea ice numerical simulation and forecasting should be applied to design anti-ice structures and to reduce ice-induced economic losses. As a project co-financed by the National Science Foundation of China and the China National Offshore Oil Bohai Corporation, the study on 揝ea Ice Numerical Simulation and Its Engineering Application in the Bohai Sea?was conducted. According to the field observations of ice conditions and ice-induced structure vibrations in the past winters at the JZ2O-2 area of Liaodong Bay, some computational parameters in the sea ice numerical model were determined, and the ice-induced structure vibrations of the MUQ platform were analyzed on the base of sea ice numerical simulation and the research of ice-structure interactions. Based on the analysis of the numerical simulation of Polar and its correlative research, two different computational methods were introduced in details while considering the ice features of the Bohai Sea,, which were Eularian Finite Different Method and Lagrangian Smoothed Particle Hydrodynamics respectively. In order to determine the computational parameters in the sea ice numerical model considering the ice characteristics of Bohai Sea, the author devoted to the field ice survey in the past 7 winters, and a great lot valuable data was obtained. Based on the measured data, the solar radiation at the ice surface in the whole ice period was analyzed, and its influences on the other thermodynamic factors of ice cover were discussed. The oceanic heat flux in the different ice season of the JZ2O-2 area was calculated with the residual method, and the effects of meteorological and hydrological conditions, ice thickness and sea ice type were discussed. Three calculative methods to determine sea ice drag coefficients, i.e. eddy correlation method, profile method and momentum method, were discussed, and their application conditions were analyzed respectively. The drag coefficients of level ice under low compactness were obtained with momentum method. According to the environmental conditions of shallow water, low salinity and intensive tide in the Bohai Sea, the sea ice thermodynamic and dynamic factors are different with other sea areas. The calculative methods for solar radiation, long wave radiation, sensible heat flux, latent heat flux at ice surface, conductive heat flux in ice cover and the oceanic heat flux under ice cover were discussed. Based on the mechanism of ice growth and the numerical test, the concept of diagnostic thickness was established, and the existing conditions of diagnostic thickness were analyzed. Under different air temperature, wind velocity, relative humidity and oceanic heat flux, the diagnostic thickness was calculated. In the analysis of sea ice dynamics, the drag forces, internal ice force, Coriolis?force and ocean tilt effect were calculated and contrasted. Based on the field observations, the physical and geometrical characteristics of ice ridges were discussed. Considering the flexural failure and buckling failure in ice ridging process, a mechanical model was established to calculate the height of ridge sail. Ice ridge design parameters were determined in different area of Bohai Sea. In the sea ice numerical simulation of Liaodong Bay, the Eularian Finite Difference Method was adopted. According更多还原