获取高分辨率的风场数据和气压场数据是精确模拟台风浪的基础,采用经验公式构建台风风场和气压场对海浪模式进行驱动,无法反映台风影响下海气动力过程,难以提供高精度的风场、气压场数据。本文基于中尺度大气模式WRF(Weather Research a...获取高分辨率的风场数据和气压场数据是精确模拟台风浪的基础,采用经验公式构建台风风场和气压场对海浪模式进行驱动,无法反映台风影响下海气动力过程,难以提供高精度的风场、气压场数据。本文基于中尺度大气模式WRF(Weather Research and Forecasting model)和第三代海浪模式SWAN(Simulating WAves Nearshore model),构建了南中国海地区大气—海浪实时双向耦合模式,针对超强台风"威马逊"进行数值模拟。将数值模拟结果与现场观测结果及卫星高度计观测结果进行对比验证,验证结果表明,本文建立的WRF-SWAN耦合模式在对台风"威马逊"影响下的南中国海台风浪的模拟中展现出较高的模拟精度,揭示了台风风场分布和台风浪分布在空间上的"右偏性"不对称分布特征及其形成机制。基于WRF和SWAN建立的大气-海浪实时双向耦合模式能够准确模拟台风动力过程以及台风浪的时空分布特征,可以推广用于南中国海地区台风浪的模拟分析。展开更多
The motion of particle clouds(i.e.,sediment clouds)usually can be found in engineering applications such as wastewater discharge,land reclamation,and marine bed capping.In this paper,a series of laboratory tests are c...The motion of particle clouds(i.e.,sediment clouds)usually can be found in engineering applications such as wastewater discharge,land reclamation,and marine bed capping.In this paper,a series of laboratory tests are conducted on coral sand to investigate the shape feature of the single particle and the mixing processes of the coral sand particle clouds.The shape of coral sand particle is measured and quantified.The experimental results demonstrate that the shape of coral sand particles tends to be spherical as the particle size decreases,and empirical equations were established to explain the variation of D50 and fS,50 of coral sand.Compared with the silica sand,the evolution of the coral sand particle cloud still experiences three stages,but the threshold for the Reynolds number of particle clouds entering the next stage changes.Further,the normalized axial distance of the coral sand particle clouds is 58%smaller.The frontal velocity exhibits similar varying tendency for the coral sand particle cloud.Considering the difference in shape between coral sand particles and silica sand particles,a semi-empirical formula was proposed based on the original silica sand prediction formula by adding the shape factor and the experimental data of 122μm≤D_(50)≤842μm.It can predict the frontal velocity of the coral sand particle clouds.展开更多
文摘获取高分辨率的风场数据和气压场数据是精确模拟台风浪的基础,采用经验公式构建台风风场和气压场对海浪模式进行驱动,无法反映台风影响下海气动力过程,难以提供高精度的风场、气压场数据。本文基于中尺度大气模式WRF(Weather Research and Forecasting model)和第三代海浪模式SWAN(Simulating WAves Nearshore model),构建了南中国海地区大气—海浪实时双向耦合模式,针对超强台风"威马逊"进行数值模拟。将数值模拟结果与现场观测结果及卫星高度计观测结果进行对比验证,验证结果表明,本文建立的WRF-SWAN耦合模式在对台风"威马逊"影响下的南中国海台风浪的模拟中展现出较高的模拟精度,揭示了台风风场分布和台风浪分布在空间上的"右偏性"不对称分布特征及其形成机制。基于WRF和SWAN建立的大气-海浪实时双向耦合模式能够准确模拟台风动力过程以及台风浪的时空分布特征,可以推广用于南中国海地区台风浪的模拟分析。
基金financially supported by the National Natural Science Foundation of China(Grant No.51839002,51979014 and 52271257)the Natural Science Foundation of Hunan Province(Grant No.2022JJ10047)the Scientific Research Innovation Project of Hunan Graduate(Grant No.CX20200858).
文摘The motion of particle clouds(i.e.,sediment clouds)usually can be found in engineering applications such as wastewater discharge,land reclamation,and marine bed capping.In this paper,a series of laboratory tests are conducted on coral sand to investigate the shape feature of the single particle and the mixing processes of the coral sand particle clouds.The shape of coral sand particle is measured and quantified.The experimental results demonstrate that the shape of coral sand particles tends to be spherical as the particle size decreases,and empirical equations were established to explain the variation of D50 and fS,50 of coral sand.Compared with the silica sand,the evolution of the coral sand particle cloud still experiences three stages,but the threshold for the Reynolds number of particle clouds entering the next stage changes.Further,the normalized axial distance of the coral sand particle clouds is 58%smaller.The frontal velocity exhibits similar varying tendency for the coral sand particle cloud.Considering the difference in shape between coral sand particles and silica sand particles,a semi-empirical formula was proposed based on the original silica sand prediction formula by adding the shape factor and the experimental data of 122μm≤D_(50)≤842μm.It can predict the frontal velocity of the coral sand particle clouds.