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A New Method for Deriving High-Vertical-Resolution Wind Vector Data from the L-Band Radar Sounding System in China
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作者 Fang YUAN Zijiang ZHOU Jie LIAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2192-2202,共11页
High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso-and microscale atmosphere. However, the current algorithm used in China's L-band radar sounding system for ... High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso-and microscale atmosphere. However, the current algorithm used in China's L-band radar sounding system for calculating highvertical-resolution wind vectors excessively smooths the data, resulting in significant underestimation of the calculated kinetic energy of gravity waves compared to similar products from other countries, which greatly limits the effective utilization of the data. To address this issue, this study proposes a novel method to calculate high-vertical-resolution wind vectors that utilizes the elevation angle, azimuth angle, and slant range from L-band radar. In order to obtain wind data with a stable quality, a two-step automatic quality control procedure, including the RMSE-F(root-mean-square error F) test and elemental consistency test are first applied to the slant range data, to eliminate continuous erroneous data caused by unstable signals or radar malfunctions. Then, a wind calculation scheme based on a sliding second-order polynomial fitting is utilized to derive the high-vertical-resolution radiosonde wind vectors. The evaluation results demonstrate that the wind data obtained through the proposed method show a high level of consistency with the high-resolution wind data observed using the Vaisala Global Positioning System and the data observed by the new Beidou Navigation Sounding System. The calculation of the kinetic energy of gravity waves in the recalculated wind data also reaches a level comparable to the Vaisala observations. 展开更多
关键词 L-band radar sounding system upper air high-vertical-resolution radiosonde wind vectors quality control polynomial fitting
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Retrieval algorithm of sea surface wind vectors for WindSat based on a simple forward model 被引量:4
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作者 赵屹立 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期210-218,共9页
WindSat/Coriolis is the first satellite-borne polarimetric microwave radiometer, which aims to improve the potential of polarimetric microwave radiometry for measuring sea surface wind vectors from space. In this pape... WindSat/Coriolis is the first satellite-borne polarimetric microwave radiometer, which aims to improve the potential of polarimetric microwave radiometry for measuring sea surface wind vectors from space. In this paper, a wind vector retrieval algorithm based on a novel and simple forward model was developed for WindSat. The retrieval algorithm of sea surface wind speed was developed using multiple linear regression based on the simulation dataset of the novel forward model. Sea surface wind directions that minimize the difference between simulated and measured values of the third and fourth Stokes parameters were found using maximum likelihood estimation, by which a group of ambiguous wind directions was obtained. A median filter was then used to remove ambiguity of wind direction. Evaluated with sea surface wind speed and direction data from the U.S. National Data Buoy Center (NDBC), root mean square errors are 1.2 rn/s and 30~ for retrieved wind speed and wind direction, respectively. The evaluation results suggest that the simple forward model and the retrieval algorithm are practicable for near-real time applications, without reducing accuracy. 展开更多
关键词 polarimetric microwave radiometer sea surface wind vector retrieval algorithm windSat
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Influence of Wind Vector Structure Variation of Typhoon "Catfish" Circulation on Its Pathway Mutation 被引量:1
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作者 WANG Yuan-chao,LIN Bao-ting Yulin Meteorological Bureau in Guangxi,Yulin 537000,China 《Meteorological and Environmental Research》 CAS 2011年第7期15-18,共4页
[Objective] The research aimed to study the wind vector structure variation of No.1013 strong typhoon 'catfish',and its influence on typhoon pathway mutation.[Method] According to the theory that the asymmetri... [Objective] The research aimed to study the wind vector structure variation of No.1013 strong typhoon 'catfish',and its influence on typhoon pathway mutation.[Method] According to the theory that the asymmetric structure of typhoon vortex had influence on typhoon movement,the center of No.1013 super typhoon 'catfish' was as the coordinate origin,and 850,500 hPa tangential rotation speeds within 300-500 km were decomposed into u and v components.The composite force movement tendency of typhoon was analyzed.The wind vector structure variation of No.1013 strong typhoon 'catfish' and its influence on typhoon pathway mutation were discussed.[Result] At the quick movement stage of No.1013 strong typhoon,the wind vector had obvious asymmetric structure.When the typhoon rotated in situ,the wind vector presented symmetric structure.When ΔU,ΔV and composite wind vector had obvious variations,the composite force of typhoon changed,and the moved direction also would change.The asymmetric structure of wind speed near 300-500 km around 500 and 850 hPa typhoon centers was favorable for tendency of moved pathway.The pointed directions of ΔU,ΔV and composite wind vector could be as the direction of composite force movement of typhoon.[Conclusion] The research provided reference basis for typhoon prevention. 展开更多
关键词 Typhoon 'catfish' wind vector structure Pathway mutation Influence analysis China
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An advanced wind vector retrieval algorithm for the rotating fan-beam scatterometer
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作者 XIE Xuetong WEN Ya HUANG Zhou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第5期83-89,共7页
The rotating fan-beam scatterometer (RFSCAT) is a new type of satellite scatterometer that is proposed approximately 10 a ago. However, similar to other rotating scatterometers, relatively larger wind retrieval erro... The rotating fan-beam scatterometer (RFSCAT) is a new type of satellite scatterometer that is proposed approximately 10 a ago. However, similar to other rotating scatterometers, relatively larger wind retrieval errors occur in the nadir and outer regions compared with the middle regions of the swath. For the RFSCAT with the given parameters, a wind direction retrieval accuracy decreases by approximately 9 in the outer regions compared with the middle region. To address this problem, an advanced wind vector retrieval algorithm for the RFSCAT is presented. The new algorithm features an adaptive extension of the range of wind direction for each wind vector cell position across the whole swath according to the distribution histogram of a retrieved wind direction bias. One hundred orbits of Level 2A data are simulated to validate and evaluate the new algorithm. Retrieval experiments demonstrate that the new advanced algorithm can effectively improve the wind direction retrieval accuracy in the nadir and outer regions of the RFSCAT swath. Approximately 1.6 and 9 improvements in the wind direction retrieval are achieved for the wind vector cells located at the nadir and the edge point of the swath, respectively. 展开更多
关键词 rotating fan-beam scatterometer objective function wind vector retrieval distribution histogram ofbias wind direction extension
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Evaluating vector winds over eastern China in 2022 predicted by the CMA-MESO model and ECMWF forecast
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作者 Fang Huang Mingjian Zeng +4 位作者 Zhongfeng Xu Boni Wang Ming Sun Hangcheng Ge Shoukang Wu 《Atmospheric and Oceanic Science Letters》 2025年第4期41-47,共7页
Vector winds play a crucial role in weather and climate,as well as the effective utilization of wind energy resources.However,limited research has been conducted on treating the wind field as a vector field in the eva... Vector winds play a crucial role in weather and climate,as well as the effective utilization of wind energy resources.However,limited research has been conducted on treating the wind field as a vector field in the evaluation of numerical weather prediction models.In this study,the authors treat vector winds as a whole by employing a vector field evaluation method,and evaluate the mesoscale model of the China Meteorological Administration(CMA-MESO)and ECMWF forecast,with reference to ERA5 reanalysis,in terms of multiple aspects of vector winds over eastern China in 2022.The results show that the ECMWF forecast is superior to CMA-MESO in predicting the spatial distribution and intensity of 10-m vector winds.Both models overestimate the wind speed in East China,and CMA-MESO overestimates the wind speed to a greater extent.The forecasting skill of the vector wind field in both models decreases with increasing lead time.The forecasting skill of CMA-MESO fluctuates more and decreases faster than that of the ECMWF forecast.There is a significant negative correlation between the model vector wind forecasting skill and terrain height.This study provides a scientific evaluation of the local application of vector wind forecasts of the CMA-MESO model and ECMWF forecast. 展开更多
关键词 Model evaluation vector winds CMA-MESO ECMWF Forecasting skill
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Vector Dominating Multi-objective Evolution Algorithm for Aerodynamic-Structure Integrative Design of Wind Turbine Blade 被引量:1
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作者 Wang Long Wang Tongguang +1 位作者 Wu Jianghai Ke Shitang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第1期1-8,共8页
A novel multi-objective optimization algorithm incorporating vector method and evolution strategies,referred as vector dominant multi-objective evolutionary algorithm(VD-MOEA),is developed and applied to the aerodynam... A novel multi-objective optimization algorithm incorporating vector method and evolution strategies,referred as vector dominant multi-objective evolutionary algorithm(VD-MOEA),is developed and applied to the aerodynamic-structural integrative design of wind turbine blades.A set of virtual vectors are elaborately constructed,guiding population to fast move forward to the Pareto optimal front and dominating the distribution uniformity with high efficiency.In comparison to conventional evolution algorithms,VD-MOEA displays dramatic improvement of algorithm performance in both convergence and diversity preservation when handling complex problems of multi-variables,multi-objectives and multi-constraints.As an example,a 1.5 MW wind turbine blade is subsequently designed taking the maximum annual energy production,the minimum blade mass,and the minimum blade root thrust as the optimization objectives.The results show that the Pareto optimal set can be obtained in one single simulation run and that the obtained solutions in the optimal set are distributed quite uniformly,maximally maintaining the population diversity.The efficiency of VD-MOEA has been elevated by two orders of magnitude compared with the classical NSGA-II.This provides a reliable high-performance optimization approach for the aerodynamic-structural integrative design of wind turbine blade. 展开更多
关键词 wind turbine multi-objective optimization vector method evolution algorithm
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Combination of Model-based Observer and Support Vector Machines for Fault Detection of Wind Turbines 被引量:11
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作者 Nassim Laouti Sami Othman +1 位作者 Mazen Alamir Nida Sheibat-Othman 《International Journal of Automation and computing》 EI CSCD 2014年第3期274-287,共14页
Support vector machines and a Kalman-like observer are used for fault detection and isolation in a variable speed horizontalaxis wind turbine composed of three blades and a full converter. The support vector approach ... Support vector machines and a Kalman-like observer are used for fault detection and isolation in a variable speed horizontalaxis wind turbine composed of three blades and a full converter. The support vector approach is data-based and is therefore robust to process knowledge. It is based on structural risk minimization which enhances generalization even with small training data set and it allows for process nonlinearity by using flexible kernels. In this work, a radial basis function is used as the kernel. Different parts of the process are investigated including actuators and sensors faults. With duplicated sensors, sensor faults in blade pitch positions,generator and rotor speeds can be detected. Faults of type stuck measurements can be detected in 2 sampling periods. The detection time of offset/scaled measurements depends on the severity of the fault and on the process dynamics when the fault occurs. The converter torque actuator fault can be detected within 2 sampling periods. Faults in the actuators of the pitch systems represents a higher difficulty for fault detection which is due to the fact that such faults only affect the transitory state(which is very fast) but not the final stationary state. Therefore, two methods are considered and compared for fault detection and isolation of this fault: support vector machines and a Kalman-like observer. Advantages and disadvantages of each method are discussed. On one hand, support vector machines training of transitory states would require a big amount of data in different situations, but the fault detection and isolation results are robust to variations in the input/operating point. On the other hand, the observer is model-based, and therefore does not require training, and it allows identification of the fault level, which is interesting for fault reconfiguration. But the observability of the system is ensured under specific conditions, related to the dynamics of the inputs and outputs. The whole fault detection and isolation scheme is evaluated using a wind turbine benchmark with a real sequence of wind speed. 展开更多
关键词 Fault detection and isolation wind turbine Kalman-like observer support vector machines data-based classification
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基于简支绕组横梁算法的变压器绕组形变矢量化监测模型 被引量:1
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作者 范晓舟 袁洁平 +3 位作者 薛峰 王湘女 律方成 耿江海 《电工技术学报》 北大核心 2025年第5期1639-1651,共13页
变压器绕组状态监测非常重要,为精确地监测变压器绕组变形方向与变形程度,该文结合简支横梁原理与布里渊光时域分析技术,提出了针对变压器绕组的形变矢量化监测算法。基于材料力学理论推导,建立了布里渊频移量与绕组形变轴向、径向分量... 变压器绕组状态监测非常重要,为精确地监测变压器绕组变形方向与变形程度,该文结合简支横梁原理与布里渊光时域分析技术,提出了针对变压器绕组的形变矢量化监测算法。基于材料力学理论推导,建立了布里渊频移量与绕组形变轴向、径向分量关系式,利用布里渊光时域分析技术建立了变压器绕组形变矢量化监测模型。通过对光纤复合导线和内置光纤的35 kV绕组施加轴向形变和径向形变,借助布里渊光时域反射技术完成了形变监测,验证了监测模型的准确性。结果表明,复合导线实验中轴向形变测量平均误差为6.60%,径向形变测量平均误差为5.88%;内置光纤的35 kV绕组实验中轴向形变平均误差为9.63%,径向形变平均误差为5.18%。实验结果验证了绕组形变矢量化监测模型可实现绕组形变方向和形变程度的监测,有效地提高绕组形变程度的监测精度。 展开更多
关键词 绕组形变 矢量化监测 光纤传感 简支绕组横梁
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基于PSO−SVR的掘进工作面风温预测 被引量:1
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作者 李延河 万志军 +6 位作者 于振子 苟红 赵万里 周嘉乐 师鹏 甄正 张源 《煤炭科学技术》 北大核心 2025年第1期183-191,共9页
随着我国浅部煤炭资源的逐渐枯竭,矿井开采深度日益增大,热害问题也随之加剧。采掘作业空间是井下的主要热害场所,对其进行热害防治是矿井安全高效生产的重要基础。矿井热害治理的前提是明确其冷负荷,因此对采掘作业空间风温进行精准预... 随着我国浅部煤炭资源的逐渐枯竭,矿井开采深度日益增大,热害问题也随之加剧。采掘作业空间是井下的主要热害场所,对其进行热害防治是矿井安全高效生产的重要基础。矿井热害治理的前提是明确其冷负荷,因此对采掘作业空间风温进行精准预测意义重大。建立了基于PSO-SVR(基于粒子群的支持向量回归)的掘进工作面风温预测模型,利用模型中的惩罚因子C和核函数参数g对模型进行了寻优。通过现场实测及文献调研,建立了掘进工作面风温预测训练样本集。通过与最小二乘法估计MLR模型和经“试错法”标定参数的常规SVR模型进行对比,分析了PSO-SVR算法的优势。将PSO-SVR算法模型应用于平煤十矿己-24120保护层风巷风温预测,并依据风温预测结果,指导了制冷机组的选型和降温方案设计。结果表明:PSO-SVR模型预测性能最优,模型绝对误差百分比仅为1.85%,较常规SVR模型减小了55.9%,可见PSO优化模型参数对于提高SVR拟合度、泛化性及预测精度具有重要作用。巷道每掘进100m,工作面风流平均温升0.16℃,掘进至2000m时巷道迎头风温升至35.8℃。己-24120保护层风巷需冷量为1083.28kW,设计制冷机组总制冷量为1085 kW。己-24120保护层风巷实施降温后,工作面平均温降8.6℃,降温效果显著,表明了PSO-SVR掘进工作面风温预测模型的可靠性和可行性。 展开更多
关键词 掘进工作面 风温预测 粒子群 支持向量回归 矿井降温
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直驱式永磁风力发电系统实验平台开发
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作者 颜建虎 王宝华 +1 位作者 刘晋宏 李文龙 《电气电子教学学报》 2025年第1期230-233,共4页
针对实验室条件开发了直驱式风力发电系统教学平台,分别利用两台24 V永磁电机搭建直驱式对拖系统,其中一台实现风力机特性模拟,另一台实现发电机能量转换。开发了基于TI 28335MCU的双电机驱动和基于C#的上位机。该实验平台具备二次开发... 针对实验室条件开发了直驱式风力发电系统教学平台,分别利用两台24 V永磁电机搭建直驱式对拖系统,其中一台实现风力机特性模拟,另一台实现发电机能量转换。开发了基于TI 28335MCU的双电机驱动和基于C#的上位机。该实验平台具备二次开发和先进的控制算法,可开展永磁电机矢量控制以及风电系统最大功率追踪控制等多种实验,能够为电机驱动控制以及新能源发电等开放性实验课程提供支撑。 展开更多
关键词 风力发电系统 永磁电机 矢量控制
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FY-3E海面风矢量产品质量评估分析
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作者 姚爽 姜晓飞 +3 位作者 张涛 姚燕 牛宁 付雅芳 《海洋预报》 北大核心 2025年第5期11-21,共11页
为评估风云三号E星(FY-3E)海面风矢量产品质量,利用浮标风场观测及海洋二号B星(HY-2B)海面风产品对FY-3E海面风进行验证。结果表明:相较于浮标观测,FY-3E的C波段、Ku波段及双波段海面风速均呈系统性负偏差,均方根误差(RMSE)分别为1.85 ... 为评估风云三号E星(FY-3E)海面风矢量产品质量,利用浮标风场观测及海洋二号B星(HY-2B)海面风产品对FY-3E海面风进行验证。结果表明:相较于浮标观测,FY-3E的C波段、Ku波段及双波段海面风速均呈系统性负偏差,均方根误差(RMSE)分别为1.85 m/s、1.52 m/s和1.54 m/s,风向RMSE分别为23.17°、22.47°和22.77°。空间分布上,热带太平洋地区风速RMSE较大,近海海域风向RMSE较大。FY-3E海面风产品总体满足风速RMSE小于2 m/s、风向RMSE小于25°的精度设计指标,且Ku波段产品质量略优于双波段,明显优于C波段。FY-3E与HY-2B海面风产品的一致性较好,二者风速、风向线性回归系数均大于0.9,平均偏差均接近0,RMSE分别为0.48 m/s和10.50°,其RMSE大值区主要位于赤道附近海域。 展开更多
关键词 风云三号E星 海面风矢量 质量评估 海洋二号B星 浮标
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基于全极化微波辐射计WindSat亮温数据的海面风场反演 被引量:6
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作者 刘璟怡 王振占 +1 位作者 殷晓斌 姜景山 《高技术通讯》 EI CAS CSCD 北大核心 2008年第5期519-524,共6页
根据全极化微波辐射传输理论,利用双尺度模式建立了海面辐射亮温的反演算法,并且利用美国发射的全球第一个星载全极化微波辐射计(WindSat)在轨运行期间的亮温数据进行了海面风场的反演,重点分析了风向反演的模糊度问题,并对风场反演结... 根据全极化微波辐射传输理论,利用双尺度模式建立了海面辐射亮温的反演算法,并且利用美国发射的全球第一个星载全极化微波辐射计(WindSat)在轨运行期间的亮温数据进行了海面风场的反演,重点分析了风向反演的模糊度问题,并对风场反演结果进行了评估。研究结果初步验证了全极化辐射计在卫星上遥感海面风场的能力:与美国国家环境预报中心(NECP)的数据进行比较,反演的风速误差为1.15m/s,5m/s 以上风速下的风向误差为21°;与 TAO 浮标数据进行比较,风速误差为1.4m/s,风速5m/s 以上的风向误差为20.5°。 展开更多
关键词 全极化微波辐射计 windSat 风场反演 误差分析
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一种针对Windsat极化辐射计的海面风场反演方法 被引量:5
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作者 刘璟怡 王振占 +1 位作者 殷晓斌 姜景山 《遥感技术与应用》 CSCD 2007年第2期210-215,共6页
星载极化微波辐射计(Windsat)是美国于2003年1月6日发射的全球第一颗星载极化微波辐射计卫星,目的是为了验证极化辐射计在卫星上遥感海面风场的能力。针对Windsat在轨运行期间的数据,研究了风场反演的海洋和大气算法,进行了全球海面风... 星载极化微波辐射计(Windsat)是美国于2003年1月6日发射的全球第一颗星载极化微波辐射计卫星,目的是为了验证极化辐射计在卫星上遥感海面风场的能力。针对Windsat在轨运行期间的数据,研究了风场反演的海洋和大气算法,进行了全球海面风场的反演,同时反演出其它地球物理参数。最后利用同步的其它数据对反演结果进行了验证。本文在极化辐射计风场反演方法和算法研究方面做了初步的尝试。 展开更多
关键词 星载极化微波辐射计 在轨定标 地物参数算法 风场反演
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2023年白洋淀不同区域湖陆风特征分析
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作者 王琼 陈军明 +4 位作者 索春男 刘姝 马凤莲 王振超 卢硕 《海洋湖沼通报(中英文)》 北大核心 2025年第4期94-103,共10页
雄安新区是“千年大计,国家大事”,白洋淀位于雄安新区中南部,其湖泊效应对雄安新区及华北地区的天气气候及水资源起到调节作用。本文利用白洋淀及周边共13站观测资料,采用天气学和统计方法,分析了白洋淀地区不同区域湖陆风多尺度变化... 雄安新区是“千年大计,国家大事”,白洋淀位于雄安新区中南部,其湖泊效应对雄安新区及华北地区的天气气候及水资源起到调节作用。本文利用白洋淀及周边共13站观测资料,采用天气学和统计方法,分析了白洋淀地区不同区域湖陆风多尺度变化特征。结果表明:2023年白洋淀不同区域均有湖陆风现象存在,风向昼夜交替。平均而言,近淀区v方向(南北方向)和u方向(东西方向)站点的平均风速均存在明显反位相特征,最大湖风0.5 m/s,均出现在午后(13—16时),最大陆风0.4 m/s,均出现在早晨到上午(6—9时),湖风大于陆风,淀北和淀东湖风强于淀南、淀西和淀中,且持续时间长;淀内水体站v方向湖风形成较u方向晚1 h,淀北水体湖风更强,达0.5 m/s;位于远淀区的城区站在v方向有明显的湖陆风特征,安新最早,容城最晚,湖风最大0.6~0.7 m/s,均较淀内和近淀区大,但u方向湖陆风不明显。湖陆风也存在明显月和季节变化,1—6月最强,10—12月次之,7—9月最小,春季最强,冬季次之,夏季和秋季相对较弱。最后通过2023年4月18日—19日湖陆风日个例及其雄安睿思实况场分析,结果与湖陆风特征基本一致,体现了白洋淀不同区域存在昼夜风向转换和风速增大的特点。 展开更多
关键词 白洋淀 风矢量 湖陆风 天气个例
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基于摩擦纳米发电机的输电线路微风振动自驱动传感技术
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作者 高思航 刘咏熙 +3 位作者 王锐 罗小婷 韦昊 何维晟 《电力工程技术》 北大核心 2025年第5期188-197,共10页
随着泛在电力物联网的快速发展,大量传感监测节点部署在电力系统的各个环节,用于实时监测电力装备运行状态及周围环境参数。当前传统供电方式已难以满足电力系统传感节点的供电需求,尤其是户外复杂环境下的输电系统,因此利用输电系统周... 随着泛在电力物联网的快速发展,大量传感监测节点部署在电力系统的各个环节,用于实时监测电力装备运行状态及周围环境参数。当前传统供电方式已难以满足电力系统传感节点的供电需求,尤其是户外复杂环境下的输电系统,因此利用输电系统周围环境中的微能量为各种传感器供电成为潜在的解决方案。为此,文中面向电力输电场景,基于摩擦纳米发电机(triboelectric nanogenerator,TENG),将旋转型TENG与扑动型TENG进行结合,提出一种自供电多风向驱动的能量采集器,由基于旋转型TENG的风能采集模块和基于扑动型TENG的风矢量传感模块两部分组成。首先,通过测试风能采集模块的输出特性,提出备用电源的混合供电策略,实现由低到高多级风速下的蓝牙温湿度传感器高效供电。其次,验证表明风矢量传感模块可灵敏响应2.6~13.5 m/s范围内的8个方向风矢量,并建立输电线路截面风向角、风速范围与导线微风振动的逻辑关联,用于评估导线异常振动。最后,在此基础上开发由能量采集器、八通道信号采集电路、LabVIEW上位机构成的环境温湿度与风矢量监测的自驱动传感系统,可实时监测温度、湿度、风速、风向等参数,并通过分析多风向矢量信息实现导线微风振动预警。 展开更多
关键词 电力物联网 摩擦纳米发电机(TENG) 输电线路 风能采集 风矢量监测 微风振动预警
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Comparison of Wind Sat and buoy-measured ocean products from 2004 to 2013 被引量:1
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作者 ZHANG Lei SHI Hanqing +3 位作者 DU Huadong ZHU Enze ZHANG Zhihua FANG Xun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第1期67-78,共12页
To evaluate the ocean surface wind vector and the sea surface temperature obtained from WindSat, we compare these quantities over the time period from January 2004 to December 2013 with moored buoy measurements. The m... To evaluate the ocean surface wind vector and the sea surface temperature obtained from WindSat, we compare these quantities over the time period from January 2004 to December 2013 with moored buoy measurements. The mean bias between the WindSat wind speed and the buoy wind speed is low for the low frequency wind speed product (WSPD_LF), ranging from -0.07 to 0.08 m/s in different selected areas. The overall RMS error is 0.98 m/s for WSPD_LF, ranging from 0.82 to 1.16 m/s in different selected regions. The wind speed retrieval result in the tropical Ocean is better than that of the coastal and offshore waters of the United States. In addition, the wind speed retrieval accuracy ofWSPD LF is better than that of the medium frequency wind speed product. The crosstalk analysis indicates that the WindSat wind speed retrieval contains some cross influences from the other geophysical parameters, such as sea surface temperature, water vapor and cloud liquid water. The mean bias between the WindSat wind direction and the buoy wind direction ranges from -0.46° to 1.19° in different selected regions. The overall RMS error is 19.59° when the wind speed is greater than 6 m/s. Measurements of the tropical ocean region have a better accuracy than those of the US west and east coasts. Very good agreement is obtained between sea surface temperatures of WindSat and buoy measurements in the tropical Pacific Ocean; the overall RMS error is only 0.36℃, and the retrieval accuracy of the low latitudes is better than that of the middle and high latitudes. 展开更多
关键词 windSat polarimetric microwave radiometer wind vector sea surface temperature validation
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复合式高速直升机非定常旋翼空气动力学建模
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作者 尹欣繁 安宏雷 +3 位作者 章贵川 彭先敏 王亮权 聂博文 《飞行力学》 北大核心 2025年第4期21-26,共6页
针对复合式高速直升机复杂的非线性空气动力学特性,采用矢量法推导叶素相对气流速度,基于叶素理论建立了一个可用于分析的复合式高速直升机非定常旋翼空气动力学模型。基于建立的非定常旋翼空气动力学数学模型进行了数值计算并与风洞试... 针对复合式高速直升机复杂的非线性空气动力学特性,采用矢量法推导叶素相对气流速度,基于叶素理论建立了一个可用于分析的复合式高速直升机非定常旋翼空气动力学模型。基于建立的非定常旋翼空气动力学数学模型进行了数值计算并与风洞试验结果进行了对比。结果表明,非定常旋翼空气动力学模型的数值计算结果与风洞试验结果吻合较好,具有较高的置信度和可靠性,能够用于该构型复合式高速直升机气动机理和飞行力学特性分析,以及指导飞行控制律的设计与验证。 展开更多
关键词 复合式高速直升机 旋翼空气动力学 叶素理论 矢量法 风洞试验
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宽域高超声速飞行器可调矢量喷管方案设计与性能研究
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作者 魏礼响 徐惊雷 +3 位作者 陈匡世 黄帅 葛建辉 宋光韬 《航空学报》 北大核心 2025年第8期177-194,共18页
针对宽域高速飞行器轴对称尾喷管宽域高性能、出口几何可调和高效推力矢量能力的迫切需求,设计一种宽域高超声速飞行器可调矢量喷管及内-中-外3套环调节方案,对该喷管在典型工况下进行数值模拟,分析了不同模态下喷管的流场结构和性能。... 针对宽域高速飞行器轴对称尾喷管宽域高性能、出口几何可调和高效推力矢量能力的迫切需求,设计一种宽域高超声速飞行器可调矢量喷管及内-中-外3套环调节方案,对该喷管在典型工况下进行数值模拟,分析了不同模态下喷管的流场结构和性能。结果表明,通过平动调节中、外套环的位置,喷管既可以调节出口面积,又具备推力矢量能力。非矢量模态,由于喷管出口面积可调,有效缓解了低落压比工况下的过膨胀现象,推力性能显著提高,相较于固定几何喷管,推力系数最多增加32.75%;矢量模态下,马赫数7工况最高能产生>10°的矢量角,同时推力系数仍>0.92。为进一步降低低马赫数下喷管的底阻,提出次流进气的流动控制方法,通过降低次流通道的内外压差,最大可以减少78.5%的底阻。最后开展了风洞缩比试验,试验结果与数值仿真结果吻合良好,验证了该宽域高超声速飞行器可调矢量喷管设计方案的有效性。 展开更多
关键词 宽域高速 高超声速 可调喷管 推力矢量 底阻 风洞试验
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双电源电驱动车辆开绕组永磁同步电机功率分配研究 被引量:1
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作者 王奥运 陈光 +1 位作者 贾一帆 景国玺 《电机与控制学报》 北大核心 2025年第3期74-87,共14页
针对双电源电动汽车的能量管理与驱动控制问题,对于隔离直流(DC)母线构型双逆变器开绕组永磁同步电机(PMSM)驱动系统进行定子电流优化及功率分配研究,并着重探究了动力电池与超级电容搭配下的功率分配策略。首先,建立双逆变器开绕组永... 针对双电源电动汽车的能量管理与驱动控制问题,对于隔离直流(DC)母线构型双逆变器开绕组永磁同步电机(PMSM)驱动系统进行定子电流优化及功率分配研究,并着重探究了动力电池与超级电容搭配下的功率分配策略。首先,建立双逆变器开绕组永磁同步电机驱动系统数学模型,并推导双空间矢量脉宽调制(SVPWM)架构下的双逆变器功率分配范围边界;然后,分别针对电机效率与功率分配范围提出两种定子电流矢量优化方法,并对比其稳态性能参数;最后,针对动力电池与超级电容的功率输出特性进行分析,在整车能量管理层面提出一种基于以上构型的双电源功率分配策略。使用仿真软件分别在城市道路以及市郊工况下,对所提功率分配策略进行验证。仿真结果表明,所提功率分配策略在节能性和稳定性方面具有优势。 展开更多
关键词 双电源 开绕组永磁同步电机 矢量控制 定子电流优化 功率分配 能量管理
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A Revised Satellite Cloud-Derived Wind Inversion Algorithm Based on Computer Cluster
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作者 Lili He Zhiwei Cai +4 位作者 Dantong Ouyang Changshuai Wang Yu Jiang Chong Wang Hongtao Bai 《Computers, Materials & Continua》 SCIE EI 2020年第7期373-388,共16页
In view of the satellite cloud-derived wind inversion has the characteristics of large scale,intensive computing and time-consuming serial inversion algorithm is very difficult to break through the bottleneck of effic... In view of the satellite cloud-derived wind inversion has the characteristics of large scale,intensive computing and time-consuming serial inversion algorithm is very difficult to break through the bottleneck of efficiency.We proposed a parallel acceleration scheme of cloud-derived wind inversion algorithm based on MPI cluster parallel technique in this paper.The divide-and-conquer idea,assigning winds vector inversion tasks to each computing unit,is identified according to a certain strategy.Each computing unit executes the assigned tasks in parallel,namely divide-and-rule the inversion task,so as to reduce the efficiency bottleneck of long inversion time caused by serial time accumulation.In the scheme of parallel acceleration based on MPI cluster,an algorithm based on performance prediction is proposed to effectively implement load balance of MPI clusters.Through the comparative analysis of experiment data using the parallel scheme of this parallel technology framework,it shows that this parallel technology has a certain acceleration effect on the cloud-derived wind inversion algorithm.The speedup of the MPI-based parallel algorithm reaches 14.96,which achieved the expected estimate.At the same time,this paper also proposes an efficiency optimization algorithm for cloud-derived wind inversion.In the case that the inversion of wind vector accuracy loss is minimal,the optimized algorithm execution time can be up to 13 times faster. 展开更多
关键词 Cloud-derived wind wind vector INVERSION parallel computing MPI speedup ratio
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