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SENsiTIVE NUMERICAL siMULATION AND ANALYsiS OF RAINSTORM UsiNG NESTED WRF MODEL

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Journal of Hydrodynamics 2006年第5期18卷 578-586页

作者： WANG Shu-chang huang si-xun LI Yi Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China

Nowadays, the nested grid model is widely used to increase the resolution of numerical model. An attempt to investigate the influence of the newly developed nesting technique of WRF model on the mesoscale numerical simulation of severe storm is described in this article. The results of sensitivity tests infer that the WRF model give more accurate and vivid prediction of severe storm with nesting scheme. As is shown in the tests, simulating value of the precipitation centers using nesting scheme are larger than those without using nesting scheme, which indicates that the simulating precipitation of nested storm is closer to the real rainfall. And there is obvious improvement of distribution of rain area and position of precipitation centers. According to the high resolution output data of the WRF model, deep and detailed analysis of characters of the mesoscale system that triggers the rainstorm is reported in this article, and the thermal and dynamical characters of this Meiyu front severe storm are also discussed.

关键词： WRF nesting numerical simulation mesoscale analysis

NUMERICAL EXPERIMENTS ABOUT GROWTH OF THE ENERGY OF DISTURBANCE IN A BAROCLINIC FLOW

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Journal of Hydrodynamics 2008年第4期20卷 499-506页

作者： TENG Jia-jun huang si-xun ZHANG Liang School of Science PLA University of Science and Technology Nanjing 211101 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China

This article is concerned with the growth of energy of disturbances in a baroclinic flow within a finite time period. The implicit difference scheme was applied to the linearized vorticity equation, and the disturbance energy was computed for three kinds of vertical shears. It turns out that all the disturbance energy rapidly increases initially, and during the succeeding period there are several stages of growth and decay of energy of disturbances, and from a certain time on, all the disturbance energy begins to decrease.

关键词： implicit difference scheme vertical shear linearized potential vorticity equation disturbance energy Couette flow

THEORETICAL ANALYSES AND NUMERICAL EXPERIMENTS FOR TWO-DIMENsiONAL WIND RETRIEVALS FROM siNGLE-DOPPLER DATA

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Journal of Hydrodynamics 2010年第2期22卷 185-195页

作者： huang si-xun CAO Xiao-qun DU Hua-dong ZHONG Ji-qin Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China National University of Defense Technolog Changsha 410073 China Institute of Urban Meteorology China Meteorological Administration Beijing 100089 China

Based on variational adjoint methods,theoretical analyses and numerical experiments are performed for retrievals of two-dimensional winds and related parameters from single-Doppler radar data in polar *** the method,the reflectivity conservation equation is used as the governing equation and the mass continuity equation as a weak *** the same time,the stable functional of regularization and background field are also introduced in the cost *** on the ideal experiments with artificial data,real two-dimensional wind fields are retrieved with low-altitude data from the Nanjing Doppler Radar Station,and the results are encouraging and promising.

关键词： single-Doppler retrievals adjoint methods regularization methods two-dimensional wind

STUDIES ON RETRIEVAL OF THE TURBULIVITY OF ATMOSPHERIC BOUNDARY LAYER

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Journal of Hydrodynamics 2006年第2期18卷 177-183页

作者： WANG Ting-fang huang si-xun XIANG Jie Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China Center of Meteorology Chengdu Air Force Chengdu 610041China Key Laboratory of Meso-Scale Severe Weather/MOE Depariment of Atmospheric Sciences Nanjing UniversityNanjing 210093 China

The variational adjoint method was applied to retrieving the turbulivity of the atmospheric Ekman boundary layer along with the regularization principle, The validity of the method was verified by using the idealized data, and then the turbulivity profile and the geostrophic wind profile were retrieved through it for real observational wind filed data.

关键词： atmospheric boundary layer turbulivity,Tikhonov regularization principle parameter retrieval

GENERALIZED VARIATIONAL OPTI MAZATION ANALYsiS FOR2-D FLOW FIELD

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Journal of Hydrodynamics 2005年第4期17卷 459-465页

作者： huang si-xun XU Ding-hua LAN Wei-ren TENG Jia-jun Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China LMSWE Nanjing University Nanjing 210093 China LMSWE Nanjing University Nanjing 210093 China East China Technology Institute Fuzhou 344000 China Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China

The Variational Optimization Analysis Method （VOAM） for 2-D flow field suggested by Sasaki was reviewed first. It is known that the VOAM can he used efficiently in most cases. However, in the cases where there are high frequency noises in 2-D flow field, it appears to be inefficient. In the present paper, based on Sasaki＇s VOAM, a Generalized Variational Optimization Analysis Method （GVOAM） was proposed with regularization ideas, which could deal well with flow fields containing high frequency noises. A numerical test shows that observational data can be both variationally optimized and filtered, and therefore the GVOAM is an efficient method.

关键词： variational optimization analysis regularization methods generalized variational optimization analysis

Research Progress on Bio‑inspired Flapping‑Wing Rotor Micro Aerial Vehicle Development

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Journal of Bionic Engineering 2024年第4期21卷 1621-1643页

作者： Yingjun Pan Shijun Guo xun huang Centre for Aeronautics School of AerospaceTransport and ManufacturingCranfield UniversityBedford MK430ALUK

Flapping-wing rotor(FWR)is an innovative bio-inspired micro aerial vehicle capable of vertical take-off and *** unique design combines active flapping motion and passive wing rotation around a vertical central shaft to enhance aerodynamic *** research on FWR,though relatively new,has contributed to 6%of core journal publications in the micro aerial vehicle field over the past two *** paper presents the first comprehensive review of FWR,analysing the current state of the art,key advances,challenges,and future research *** review highlights FWR’s distinctive kinematics and aerodynamic superiority compared to traditional flapping wings,fixed wings,and rotary wings,discussing recent breakthroughs in efficient,passive wing pitching and asymmetric stroke amplitude for lift *** experiments and remote-controlled take-off and hovering tests of single and dual-motor FWR models have showcased their *** review compares FWR flight performance with well-developed insect-like flapping-wing micro aerial vehicles as the technology readiness level progresses from laboratory to outdoor flight testing,advancing from the initial flight of a 2.6 g prototype to the current free flight of a 60-gram *** review also presents ongoing research in bionic flexible wing structures,flight stability and control,and transitioning between hovering and cruise flight modes for an FWR,setting the stage for potential applications.

关键词： Flapping-wing rotor Micro aerial vehicle Bio-inspiration Flight

一种全球定位系统接收机单点定位的新算法及数值试验

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物理学报 2006年第12期55卷 6720-6726页

作者：黄思训盛峥解放军理工大学气象学院南京211101

借助于Bancroft方法快速决定全球定位系统中接收机的大概位置,可作为观测方程线性化的初值.采用最小二乘法来求解方程时,观测数据存在较大误差(即出现粗差)的情况下,最小二乘解会出现不稳定性,即问题呈不适定性.为了克服解的不适定性,... 详细信息

借助于Bancroft方法快速决定全球定位系统中接收机的大概位置,可作为观测方程线性化的初值.采用最小二乘法来求解方程时,观测数据存在较大误差(即出现粗差)的情况下,最小二乘解会出现不稳定性,即问题呈不适定性.为了克服解的不适定性,引入了正则化方法,采用正则化方法及正则化参数最优选择来提高抗粗差能力.实验结果表明,利用这种定位方法的抗粗差能力有一定的改进,这对实时、快速定位有重要意义.

关键词：全球定位系统 Bancroft方法最小二乘法正则化

雷达回波资料反演海洋波导的算法和抗噪能力研究

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物理学报 2009年第6期58卷 4328-4334页

作者：盛峥黄思训解放军理工大学气象学院南京211101

利用海洋环境中大气波导的参数化模型及电磁波传播的地型抛物方程,建立电磁波传播正问题,获得电磁波传播功率损耗.结合正演模式,通过遗传算法反演出大气波导参数,并对遗传算法参数的设置进行了讨论,对反演系统进行了抗噪能力的分析.发... 详细信息

利用海洋环境中大气波导的参数化模型及电磁波传播的地型抛物方程,建立电磁波传播正问题,获得电磁波传播功率损耗.结合正演模式,通过遗传算法反演出大气波导参数,并对遗传算法参数的设置进行了讨论,对反演系统进行了抗噪能力的分析.发现当误差小于10%时,遗传算法仍能保持较高的反演精度;当误差大于10%时,该算法的精度开始受到显著的影响.研究结果可能会对雷达仪器设计和应用提供参考.

关键词：波导电磁波传播方程遗传算法反演

变分伴随正则化方法从雷达回波反演海洋波导 Ⅰ.理论推导部分

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物理学报 2010年第6期59卷 1734-1739页

作者：盛峥黄思训解放军理工大学气象学院南京211101

针对传统统计反演算法在雷达回波反演海洋波导(RFC)方面计算量过大的问题,提出一种变分伴随正则化物理反演算法.在变分伴随方法中分别导出切线性模式、伴随方程及伴随边界条件、伴随方程求解表达式、以及泛函梯度的数学表达形式;讨论了... 详细信息

针对传统统计反演算法在雷达回波反演海洋波导(RFC)方面计算量过大的问题,提出一种变分伴随正则化物理反演算法.在变分伴随方法中分别导出切线性模式、伴随方程及伴随边界条件、伴随方程求解表达式、以及泛函梯度的数学表达形式;讨论了伴随方法求泛函梯度对复方程如何协调的问题.考虑到雷达电磁波传播的特征,选择了适当的正则化项来解决反演中的不适定问题.最后给出反演算法实施中的迭代格式.

关键词：海洋波导地型抛物方程变分伴随正则化