基于FVCOM-SWAN双向耦合模型,对渤海湾围填前后潮流场和波浪场进行模拟,分析围填海对渤海湾水动力环境的影响.结果表明:围填海对围填海区附近海域水动力环境的影响较为显著,而对远离其海域的影响较小.在主要围填海区,大部分海域月均水位在高潮位时较围填前增加,低潮位时较围填前减小,而曹妃甸东北部三港池附近海域月均水位变化与其他海域相反.涨急、落急时,月均垂向平均流速在曹妃甸围填外边界附近原潮流流向改变较大的海域、天津南港工业区和黄骅港口门附近海域增加,在其他主要围填海区减小.对波浪场的影响局限在围填海域附近,月均有效波高和周期均减小.本文还比较了是否考虑波浪作用对潮流的影响.波流共同作用与不考虑波浪作用的情况相比,大部分沿岸海域水位减小,垂向平均流速和底部切应力增加.

选择在波浪破碎模拟中表现较好的破碎指标GOMOD15和SAMOD17进行比较.首先将两者分别引入SWAN模型,然后利用实验室水槽试验(包括斜坡和平底条件)和现场观测数据比较两者对SWAN模型波浪模拟的影响.总体来看,随着坡度的逐渐变缓,SAMOD17与GOMOD15的结果差异逐渐显著,对于文中的所有算例,采用GOMOD15的模拟结果均更接近实测值.鉴于GOMOD15的更好表现且在模型计算时不需要人为调整其参数,因此在采用SWAN模型模拟波浪破碎时推荐使用.

近10多年来,我国围填海工程发展迅速,渤海海岸线变化明显,岸线变化会改变潮波传播并影响风暴潮增水.基于FVCOM海洋动力学模型,利用潮汐和风场强迫,建立了渤海风暴潮模型,根据2000年岸线和2010年岸线,分别模拟了包括台风风暴潮和寒潮风暴潮在内的4次典型风暴潮过程,对模拟数据和实测数据进行统计分析,模拟结果与实测数据基本一致.研究了岸线变化前后,渤海风暴潮对近岸增水的影响,并对曹妃甸港、天津港和黄骅港的风暴潮增水灾害进行了风险评估.

基于三维近海海洋模式——FVCOM (the finite volume coastal ocean model)海洋动力学模型,利用中尺度气象预报资料WRF (the weather research forecasting model)风场数据和网格嵌套方法,通过潮汐和风场共同驱动,建立了渤海风暴潮模型.对1997年8月的Winnie台风风暴潮进行数值模拟,研究了渤海风暴潮增减水及流场的时空变化特征.研究表明,渤海沿岸增水幅度较大,水位变化明显,潮流运动发生较大改变.利用模拟结果,研究了岸线变化对渤海湾风暴潮增水的影响.岸线变化后,曹妃甸港、天津港和黄骅港海域,风暴潮增水有不同程度的增加,渤海湾风暴潮灾害强度有增加的趋势.

波流力是浅海牧场式围栏设施中柱桩所受的主要荷载,直接影响着桩基的型式和断面尺寸.文章结合椒江大陈岛海域大型浅海牧场式围栏设施工程设计需求,分别采用目前常用的两种柱桩波流力计算方法计算了不同波浪和水流条件下最大总波流力和总波流力矩,结果表明,两者均随波高和流速的增大而增大,而受平均周期的影响较小.同时,相比于波高和平均周期,流速对两种方法计算结果差异的影响更为显著,随着流速的逐渐增大,其差异也逐渐增大.文章研究结果对今后浅海围栏设施中柱桩工程设计的方法选择和科学研究具有一定的参考价值.

Impact of wind drag coefficients in SWAN model on wave simulation was studied in the paper.Sensitivity experiments were conducted under wind speed 14 m/s,31.5 m/s and 50 m/s (representing the conditions of strong wind,strong tropical storm and strong typhoon,respectively).Haringvliet in Holland was chosen as exper-imental area.Results show that in shallow water (shallower than 20 m),the wind drag coefficient has little effect on significant wave height.When the wind speed reaches a certain speed,wave breaking becomes a major factor af-fecting the significant wave height.In deep water (deeper than 30 m),the effect of wind drag coefficients on signif-icant wave height is still small in condition of strong wind.As the wind speed increases further,the influence of wind drag coefficients on significant wave height becomes obvious gradually.The wind drag coefficient and wind speed have little influence on mean wave period whereas the wave breaking affects it significantly.According to the results of sensitivity experiments,choice of wind drag coefficients in SWAN model is suggested as follows.When the wind waves in shallow water are simulated,the default wind drag coefficient in SWAN can be directly used.As for deep water case,the default wind drag coefficient can be applied in condition of strong wind.When the wind speed is higher,the default wind drag coefficient can be tested firstly,and then it can be modified in terms of the field data if needed.

Sea temperature variation of Bohai Sea and North Yellow Sea was simulated numerically with FVCOM(finite-volume coastal ocean model). The model was driven by wind with different resolution. Effects of temporal-spatial resolution of wind field on sea temperature simulation were analyzed. The results indicated that the effect of temporal-spatial resolution of wind field on sea temperature variation showed seasonal characteristics. The variation of temperature is bigger after ther-mocline appears. The variation of temperature increases as the resolution of wind field decreases. Effect of monthly-averaged wind on temperature variation is the most significant due to the poor description of the temporal variation of wind speed.

FVCOM(finite volume coastal ocean model)was applied in this research to the simulation of the Bohai tidal system for a period of 1 year.The effects of bottom friction coefficients on the Bohai tidal system simulation were analyzed.Harmonic analysis was performed every 15 days,1 month and then 1 year in order to know the differences caused by the length of time.The results indicate that the simulated and observed harmonic constants are consistent with one another.When the open boundary conditions were the same,the amplitudes of the tide in the entire sea waters decreased as bottom friction increased.Also,the amphidromic point drifted left along with the direction of the tide propagation.The simulation systems gave better results when the bottom friction coefficients was 0.002.The time of the harmonic analysis should not be less than 1 month.