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大气动力学方程组全局分析的研究进展 被引量:10
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作者 谢志辉 丑纪范 《地球科学进展》 CAS CSCD 1999年第2期133-139,共7页
把天气预报问题提成初值问题的反问题,可以使用多时刻的历史资料去补充和完善数值预报模式。借助于几何直观可以对大气动力学方程组的极限解集进行全局定性分析,运用胞映射的概念和方法可以对大气系统的数值模式的整体特征进行全局分... 把天气预报问题提成初值问题的反问题,可以使用多时刻的历史资料去补充和完善数值预报模式。借助于几何直观可以对大气动力学方程组的极限解集进行全局定性分析,运用胞映射的概念和方法可以对大气系统的数值模式的整体特征进行全局分析和借助概率论的语言进行统计描述。还可以给出“气候”这个模糊概念的严格的数学定义及定量研究大气可预测性问题的途径。全局分析是研究气候不同于简单初值问题的另外一条道路。综述了这方面研究的最新进展。 展开更多
关键词 大气动力学 数值天气预报 大气方程组 全局分析
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Stability of weak solutions to climate dynamics model with effects of topography and non-constant external force 被引量:6
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作者 LIAN RuXu ZENG QingCun JIN JiangBo 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第1期47-59,共13页
In this paper, a climate dynamics model with the effects of topography and a non-constant external force, which consists of the Navier-Stokes equations and a temperature equation arising from the evolution process of ... In this paper, a climate dynamics model with the effects of topography and a non-constant external force, which consists of the Navier-Stokes equations and a temperature equation arising from the evolution process of the atmosphere, was considered.Under certain assumptions imposed on the initial data and by using some delicate estimates and compactness arguments, we proved the L^1-stability of weak solutions to the atmospheric equations. 展开更多
关键词 Climate dynamics atmospheric equations Weak solutions Stability topography
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Analytical study of atmospheric internal waves model with fractional approach
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作者 Trushit Patel Hardik Patel Ramakanta Meher 《Journal of Ocean Engineering and Science》 SCIE 2024年第4期326-337,共12页
This study looks at the mathematical model of internal atmospheric waves,often known as gravity waves,occurring inside a fluid rather than on the surface.Under the shallow-fluid assumption,internal atmospheric waves m... This study looks at the mathematical model of internal atmospheric waves,often known as gravity waves,occurring inside a fluid rather than on the surface.Under the shallow-fluid assumption,internal atmospheric waves may be described by a nonlinear partial differential equation system.The shallow flow model’s primary concept is that the waves are spread out across a large horizontal area before rising vertically.The Fractional Reduced Differential Transform Method(FRDTM)is applied to provide approximate solutions for any given model.This aids in the modelling of the global atmosphere,which has applications in weather and climate forecasting.For the integer-order value(α=1),the FRDTM solution is compared to the precise solution,EADM,and HAM to assess the correctness and efficacy of the proposed technique. 展开更多
关键词 Shallow-fluid equations atmospheric internal waves Time-fractional partial differential equations Fractional reduced differential transform method(FRDTM) Climate prediction
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考虑雷诺数、湿度等影响因素的涡扇发动机小偏差模型 被引量:4
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作者 吕建伟 李军 《航空动力学报》 EI CAS CSCD 北大核心 2005年第1期44-48,共5页
建立了一个考虑雷诺数、湿度等影响因素的涡扇发动机小偏差模型。通过分析 ,得到了雷诺数、湿度对涡扇发动机特性的影响系数及影响系数矩阵。以涡扇发动机为例进行计算 ,结果表明 :该模型可以定量。
关键词 航空、航天推进系统 雷诺数 湿度 小偏差 发动机特性
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Basic Pattern in Atmospheric Turbulence Model 被引量:3
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作者 FUZun-Tao ZHANGLin +1 位作者 LIUShi-Da LIUShi-Kuo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6期845-848,共4页
From the controlling equations of atmosphere motion, Prandtl's mixing length theory is used to derive the atmospheric turbulence models, such as Burgers equation model and Burgers-KdV equation model. And then the ... From the controlling equations of atmosphere motion, Prandtl's mixing length theory is used to derive the atmospheric turbulence models, such as Burgers equation model and Burgers-KdV equation model. And then the projective Riccati equations are applied to solve these atmospheric turbulence models, where much more patterns are obtained, including solitary wave pattern, singular pattern, and so on. 展开更多
关键词 atmospheric turbulence model Burgers-type equations projective Riccati equations
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一种非线性大气化学动力学方程组的新算法 被引量:2
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作者 王体健 孙照渤 《南京气象学院学报》 CSCD 1998年第3期398-404,共7页
提出了一种求解非线性大气化学动力学方程组的新算法,即预测/校正拟稳态近似法(PCQSSA),该方案集中了传统的QSSA方案和Hybrid方案的优点,具有较高的计算效率和精度,对于复杂的大气化学模式和区域污染模式较适用。
关键词 非线性 大气化学 动力学方程组 算法
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Theory of three-pattern decomposition of global atmospheric circulation 被引量:1
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作者 Shujuan HU Bingqian ZHOU +3 位作者 Chenbin GAO Zhihang XU Qingwan WANG Jifan CHOU 《Science China Earth Sciences》 SCIE EI CAS CSCD 2020年第9期1248-1267,共20页
This paper reviews the three-pattern decomposition of global atmospheric circulation(3P-DGAC)developed in recent years,including the decomposition model and the dynamical equations of global horizontal,meridional,and ... This paper reviews the three-pattern decomposition of global atmospheric circulation(3P-DGAC)developed in recent years,including the decomposition model and the dynamical equations of global horizontal,meridional,and zonal circulations.Compared with the traditional two-dimensional(2D)circulation decomposition method,the 3P-DGAC can effectively decompose the actual vertical vorticity into two components that are caused by the horizontal circulation and convergent/divergent movement(associated with the meridional and zonal circulations).It also decomposes the vertical velocity into the components of the meridional vertical circulation and the zonal vertical circulation,thus providing a new method to study the dynamical influences of convergent/divergent motions on the evolution of actual vertical vorticity and an accurate description of local vertical circulations.The 3P-DGAC is a three-dimensional(3D)circulation decomposition method based on the main characteristics of the actual atmospheric movements.The horizontal,meridional,and zonal circulations after the 3P-DGAC are the global generalization of Rossby waves in the middle-high latitudes and Hadley and Walker circulations in low latitudes.Therefore,the three-pattern decomposition model and its dynamical equations provide novel theoretical tools for studying complex interactions between middle-high and low latitude circulations as well as the physical mechanisms of the abnormal evolution of large-scale atmospheric circulations under the background of global warming. 展开更多
关键词 Horizontal circulation Meridional circulation Zonal circulation Three-pattern decomposition of global atmospheric circulation(3P-DGAC) Dynamical equations
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On a Class of Solitary Wave Solutions of Atmospheric Nonlinear Equations
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作者 R. Dhar C. Guha-Roy D. K. Sinha 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第3期357-362,共6页
In this paper, an attempt is made to study some interesting results of the coupled nonlinear equations in the atmosphere. By introducing a phase angle function ζ, it is shown that the atmospheric equations in the pr... In this paper, an attempt is made to study some interesting results of the coupled nonlinear equations in the atmosphere. By introducing a phase angle function ζ, it is shown that the atmospheric equations in the presence of specific forcing exhibit the exact and explicit solitary wave solutions under certain conditions. 展开更多
关键词 On a Class of Solitary Wave Solutions of atmospheric Nonlinear equations
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Mathematical modeling of atmospheric internal waves phenomenon and its solution by Elzaki Adomian decomposition method
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作者 Archana C.Varsoliwala Twinkle R.Singh 《Journal of Ocean Engineering and Science》 SCIE 2022年第3期203-212,共10页
This article involves the study of atmospheric internal waves phenomenon,also referred to as gravity waves.This phenomenon occurs inside the fluid,not on the surface.The model is based on a shallow fluid hypothesis re... This article involves the study of atmospheric internal waves phenomenon,also referred to as gravity waves.This phenomenon occurs inside the fluid,not on the surface.The model is based on a shallow fluid hypothesis represented by a system of nonlinear partial differential equations.The basic assumption of the shallow flow model is that the horizontal size is much larger than the vertical size.Atmospheric internal waves can be perfectly represented by this model as the waves are spread over a large horizontal area.Here we used the Elzaki Adomian Decomposition Method(EADM)to obtain the solution for the considered model along with its convergence analysis.The Adomian decomposition method together with the Elzaki transform gives the solution in a convergent series without any linearization or perturbation.Comparisons are built between the results obtained by EADM and HAM to examine the accuracy of the proposed method. 展开更多
关键词 atmospheric internal waves Shallow-fluid equations System of nonlinear PDEs Elzaki Adomian decomposition method Climate prediction
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基于两种辐射传输模型的遥感数据大气校正及结果对比分析 被引量:14
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作者 范文义 孙晓芳 +1 位作者 王岩 杨爱玲 《东北林业大学学报》 CAS CSCD 北大核心 2009年第7期121-124,共4页
通过辐射传输方程详述了大气效应对遥感图像的影响及大气校正的原理,并利用两种辐射传输模型——6S和FLAASH(基于MODTRAN)对同一区域ETM+数据的可见光、近红外波段分别进行了大气校正。从校正的结果看,两种模型均对由于大气效应引起的... 通过辐射传输方程详述了大气效应对遥感图像的影响及大气校正的原理,并利用两种辐射传输模型——6S和FLAASH(基于MODTRAN)对同一区域ETM+数据的可见光、近红外波段分别进行了大气校正。从校正的结果看,两种模型均对由于大气效应引起的辐射失真进行了辐射校正,消除了因散射增加的辐射能量,同时补偿了因吸收而损失的辐射能量,但在校正结果上存在差异。只有将两种辐射传输模型方法结合使用,才能更好地消除大气效应对研究区域的影响。 展开更多
关键词 大气校正 辐射传输方程 6S模型 MODTRAN模型 FLAASH
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沿Z型光传输管道轴向吹气对激光传输的影响 被引量:11
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作者 柳建 李树民 +2 位作者 金钢 张翔 刘顺发 《强激光与粒子束》 EI CAS CSCD 北大核心 2005年第2期164-168,共5页
针对在Z型管道中传输的高能量密度激光束受到的气体热效应问题,采用光波标量衍射方程计算光传输、N S方程计算管道内流场,仿真计算了以不同的速度沿管道轴向吹入对激光能量无吸收的气体时,由于气流扰动对出射光束远场光斑质量的影响。... 针对在Z型管道中传输的高能量密度激光束受到的气体热效应问题,采用光波标量衍射方程计算光传输、N S方程计算管道内流场,仿真计算了以不同的速度沿管道轴向吹入对激光能量无吸收的气体时,由于气流扰动对出射光束远场光斑质量的影响。结果表明,在采用纵向吹气减小气体热效应对光束传输的影响时,应尽可能采用大气量、低流速的方案,既有利于排空管道中的杂质气体,减小气体热效应,又有利于减小管道中流场密度分布的不均匀性,从而保证出射光束的质量。 展开更多
关键词 光传输 热晕 气动光学 标量衍射 N-S方程
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相对垂直加速度和中尺度大气运动方程组 被引量:10
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作者 程麟生 冯伍虎 《高原气象》 CSCD 北大核心 2003年第2期97-103,共7页
对具有强对流性质的中尺度系统运动的描写,直接采用包含准静力假设的p坐标系或σ坐标系大气运动方程组是不精确又不合理的。因此,必须发展更精确的非静力中尺度大气运动方程组。本文通过引入相对垂直加速度δ和通用(x,y,ζ,t)坐标系(简... 对具有强对流性质的中尺度系统运动的描写,直接采用包含准静力假设的p坐标系或σ坐标系大气运动方程组是不精确又不合理的。因此,必须发展更精确的非静力中尺度大气运动方程组。本文通过引入相对垂直加速度δ和通用(x,y,ζ,t)坐标系(简称ζ坐标系),导出了ζ坐标系中的非静力大气运动方程组。该方程组的垂直运动方程是非静力的,相对垂直加速度δ是可预报的;垂直加速度可由δ直接求得;而δ既直接影响速度场、位势场、质量场和地面气压场,还间接影响温度场。通过对通用ζ坐标系中非静力大气运动方程组的应用,可以很容易地获得p坐标系或σ坐标系及其它垂直坐标系中的非静力大气运动方程组;当δ为零时,则简化为一般包含准静力假设的p坐标系或σ坐标系及其它垂直坐标系中的大气运动方程组。在一般广泛使用的p坐标系或σ坐标系大气运动方程组中,因未考虑δ的贡献,对一些场的预报就会产生误差,较长时间的数值积分会使这种误差积累愈来愈大。显然,新发展的非静力大气运动方程组考虑了δ的贡献,从而消除了这种误差,所以就更为精确,也更适用于对中尺度系统运动的描写和预报。 展开更多
关键词 相对垂直加速度 中尺度大气运动方程 位势场 质量场 地面气压场 温度场
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湿大气方程组解的渐近性质 被引量:8
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作者 李建平 丑纪范 《气象学报》 CSCD 北大核心 1998年第2期187-198,共12页
研究无穷维Hilbert空间中,湿大气运动系统解的长期行为,在导得了湿大气运动方程是Hilbert空间中一个非常特殊的算子方程之后,利用算子的性质讨论了全局吸收集和全局吸引子的存在性,揭示出系统解的渐近行为表现在吸引... 研究无穷维Hilbert空间中,湿大气运动系统解的长期行为,在导得了湿大气运动方程是Hilbert空间中一个非常特殊的算子方程之后,利用算子的性质讨论了全局吸收集和全局吸引子的存在性,揭示出系统解的渐近行为表现在吸引子的结构上及系统向非绝热加热的非线性适应过程。最后指出了几个简化方程组与原方程组在解的长期行为上的根本不同,从而给出长期天气或气候研究中简化方程组必须遵循的原则。 展开更多
关键词 湿大气方程组 算子方程 渐近性质 大气 水汽
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Analysis on the Interaction between Turbulence and Secondary Circulation of the Surface Layer at Jinta Oasis in Summer 被引量:6
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作者 韩博 吕世华 奥银焕 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第3期605-620,共16页
The kinetic energy variations of mean flow and turbulence at three levels in the surface layer were calculated by using eddy covariance data from observations at Jinta oasis in 2005 summer. It is found that when the m... The kinetic energy variations of mean flow and turbulence at three levels in the surface layer were calculated by using eddy covariance data from observations at Jinta oasis in 2005 summer. It is found that when the mean horizontal flow was stronger, the turbulent kinetic energy was increased at all levels, as well as the downward mean wind at the middle level. Since the mean vertical flow on the top and bottom were both negligible at that time, there was a secondary circulation with convergence in the upper half and divergence in the lower half of the column. After consideration of energy conversion, it was found that the interaction between turbulence and the secondary circulation caused the intensification of each other. The interaction reflected positive feedback between turbulence and the vertical shear of the mean flow. Turbulent sensible and latent heat flux anomaly were also analyzed. The results show that in both daytime and at night, when the surface layer turbulence was intensified as a result of strengthened mean flow, the sensible heat flux was decreased while the latent heat flux was increased. Both anomalous fluxes contributed to the cold island effect and the moisture island effect of the oasis. 展开更多
关键词 heterogeneous atmospheric boundary layer turbulent kinetic energy equations energy con-version secondary circulation oasis effect
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台站温度质量控制中IDW算法改进及应用 被引量:7
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作者 王兴 苗春生 +1 位作者 江燕如 汪瑶 《气象科技》 2014年第4期605-611,共7页
在反距离加权插值算法的基础上,结合气象上温度随高程的变化,以及各测站垂直方向上温度场与气压场的关系,对国内地面气象观测站的温度数据进行插值算法改进。然后,从搜索半径与距离权重系数的关系,以及参与插值站点数量与距离权重系数... 在反距离加权插值算法的基础上,结合气象上温度随高程的变化,以及各测站垂直方向上温度场与气压场的关系,对国内地面气象观测站的温度数据进行插值算法改进。然后,从搜索半径与距离权重系数的关系,以及参与插值站点数量与距离权重系数的关系两个方面进行试验数据分析,试图找出相对最佳的算法参数和最小的插值误差。最后,将改进的算法应用到温度观测数据的质量控制中。结果表明:改进后的算法可明显改善因近地面逆温造成的插值误差,在台站分布较密集的我国中东部地区,温度质量检验的灵敏度可达到1至5摄氏度。 展开更多
关键词 反距离权重算法 大气静力学公式 地面站温度 质量控制
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The macroscopic mechanisms and associated atmospheric precursor environmental capacities that lead to secondary fine particle pollution 被引量:1
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作者 Dahai XU Junming CHEN 《Science China Earth Sciences》 SCIE EI CAS CSCD 2019年第12期2069-2082,共14页
This paper establishes the kinetic equations in atmospheric chemistry that describe the macroscopic mechanisms of secondary fine particle pollution generated by precursors during atmospheric self-purification.The dyna... This paper establishes the kinetic equations in atmospheric chemistry that describe the macroscopic mechanisms of secondary fine particle pollution generated by precursors during atmospheric self-purification.The dynamic and static solutions of these equations can be applied to calculate quantitative relationships between the concentration ratio of precursors and secondary fine particles as well as the physical clearance power of the atmosphere,chemical reaction rate,and the scale of a contaminated area.The dynamic solution presented here therefore corresponds with a theoretical formula for calculating the overall rate constant for the oxidation reaction of reducing pollutants in the actual atmosphere based on their local concentrations and meteorological monitoring data.In addition,the static solution presented in this paper reveals the functional relationship between the concentration of secondary fine particles and precursor emission rate as well as atmospheric self-purification capacity.This result can be applied to determine the atmospheric environmental capacity of a precursor.Hourly records collected over the last 40 years from 378 weather stations in China's Mainland as well as the spatiotemporal distribution sequence of overall oxidation reaction rates from precursors show that when the reference concentration limit of secondary fine particles is100μmol m-3,the atmospheric environmental capacity of total precursors canbe calculated as 24890×1010 mol yr-1.Thus,when the annual average concentration limit of given fine particles is 35μg m-3 and the ratio of sulfate and nitrate to 30%and 20%of the total amount of fine particles,the capacities of SO2,NOx and NH3 are 1255,1344,and 832(1010g yr-1),respectively.The clearance density of precursors for different return periods across China's Mainland under above conditions are also provided in this study. 展开更多
关键词 atmospheric chemical kinetic equations PRECURSOR of SECONDARY fine particle Overall oxidation reaction rate atmospheric SELF-PURIFICATION power atmospheric ENVIRONMENTAL capacity Clearance density Return period
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双三次数值模式与理想Lamb波、龙卷扰动对比模拟分析 被引量:4
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作者 辜旭赞 张兵 《气象科技》 2007年第5期613-620,共8页
通过"双三次曲面拟合—时间步长积分—双三次曲面拟合……",实现成为一种双三次曲面拟合新算法数值模式。它对模式大气作非线性(空间二阶可导)描述,是用数值分析(三次样条/双三次曲面)与计算方法近似求解大气运动非线性偏微... 通过"双三次曲面拟合—时间步长积分—双三次曲面拟合……",实现成为一种双三次曲面拟合新算法数值模式。它对模式大气作非线性(空间二阶可导)描述,是用数值分析(三次样条/双三次曲面)与计算方法近似求解大气运动非线性偏微分方程组。用Z坐标系高分辨率双三次数值模式,采用原始大气运动方程组和采用欧拉时间积分方案,设置理想扰动,对大气声波Lamb波做数值模拟;采用大气不可压假定,除去声波,对大气重力波龙卷扰动做数值模拟。对比模拟发现:理想Lamb波以声速在水平方向传播,扰动能量频散快,仅能在原地持续数秒钟;理想龙卷扰动则在原地可持续约1 min,且波动内圈(外圈)自下至上始终处于风场辐合(辐散)状态,具冷心结构和气压驻波特征,可因水汽进入扰动与借助凝结潜热释放而得到发展。 展开更多
关键词 双三次数值模式 原始大气运动方程组 欧拉时间积分方案 LAMB波 龙卷扰动 数值模拟
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温室大棚小气候的热力—动力学分析 被引量:4
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作者 刘春 刘思波 +2 位作者 张春辉 杨婷 李春林 《高原山地气象研究》 2012年第4期70-75,共6页
根据大棚的结构特点,利用简化的大气热力—动力学方程组,以分析和数值的方法,对大棚内温度的时空分布进行了分析。并以该模型下的解析解作为加热下大棚温度的初始场,通过对热传导方程的边界值和初始场的讨论,利用分离变量法给出了方程... 根据大棚的结构特点,利用简化的大气热力—动力学方程组,以分析和数值的方法,对大棚内温度的时空分布进行了分析。并以该模型下的解析解作为加热下大棚温度的初始场,通过对热传导方程的边界值和初始场的讨论,利用分离变量法给出了方程的简单解析解,并给出其在不同时刻的数值模拟。通过对解析解的进一步分析,得出了该模型达到定常状态的时间。这一模型可以为以后以动力学方法进一步研究小气候提供参考。 展开更多
关键词 大气热力-动力学方程组 热传导方程 初始场 边界值 定常
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The property of solutions for the equations of large-scale atmosphere with the non-stationary external forcings 被引量:2
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作者 李建平 丑纪范 《Chinese Science Bulletin》 SCIE EI CAS 1996年第7期587-590,共4页
The long-term behavior of the atmospheric evolution, which cannot be answered and solvedby the numerical experiments, must be undrstood before we design the numerical forecastmodels of the long-range weather and clima... The long-term behavior of the atmospheric evolution, which cannot be answered and solvedby the numerical experiments, must be undrstood before we design the numerical forecastmodels of the long-range weather and climate. It is necessary to carry out some studiesof basic theory. Based on the stationary external forcings, Chou studied the adjustment of the nonlinear atmospheric system tending to forcings in R^n. Then these resultswere extended to the infinite dimensional Hilbert space. For the real atmospheric system, 展开更多
关键词 solution of the atmospheric equations NON-STATIONARY external FORCING absorbing set OPERATOR equation.
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Stability for basic system of equations of atmospheric rhotion 被引量:2
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作者 施惟慧 徐明 王曰朋 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第2期261-268,共8页
The topological characteristics for the basic system of equations of atmospheric motion were analyzed with the help of method provided by stratification theory. It was proved that in the local rectangular coordinate s... The topological characteristics for the basic system of equations of atmospheric motion were analyzed with the help of method provided by stratification theory. It was proved that in the local rectangular coordinate system the basic system of equations of atmospheric motion is stable in infinitely differentiable function class. In the sense of local solution, the necessary and sufficient conditions by which the typical problem for determining solution is well posed were also given. Such problems as something about "speculating future from past" in atmospheric dynamics and how to amend the conditions for determining solution as well as the choice of underlying surface when involving the practical application were further discussed. It is also pointed out that under the usual conditions, three motion equations and continuity equation in the basic system of equations determine entirely the property of this system of equations. 展开更多
关键词 basic system of equations of atmospheric motion STABILITY stratificationtheory transversal stratum
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