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The influence of synthetic jet excitation on secondary flow in compressor cascade

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Journal of Thermal Science 2010年第6期19卷 500-504页

作者： Yanming LIU, Tuo SUN, Chaobin GUAN and Baoguo WANG School of Aerospace Engineering, beijing Institute of Technology, beijing, 100081, China Assistant Professor School of Aerospace Engineering Beijing Institute of Technology Beijing China

The detailed numerical simulation has been carried out to investigate the effect of synthetic jet excitation on the secondary flow at 5. incidence in a compressor cascade, in which the synthetic jet actuation is equipped on the suction surface. The influence of excitation position, one fixed near the trailing edge and the other fixed a little far from the trailing edge, has also been studied. The results show that unsteady disturbance of desirable synthetic jet effectively enhances the mixing of the fluid inside the separation region, which reduces the vortex intensity and the energy loss, improves the flow status in the cascade, and also suppresses velocity fluctuation near the trailing edge. Additionally, the actuation fixed near the separation region proves to be more effective and exit load distribution is more uniform due to the employment of the synthetic jet.

关键词： synthetic jet actuator compressor cascade loss velocity fluctuation

Three-dimensional decomposition method of global atmospheric circulation

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Science China Earth Sciences 2008年第3期51卷 386-402页

作者： LIU HaiTao1,2,3. HU ShuJuan4, XU Ming5.& CHOU JiFan6,7 1 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, China 2 Graduate University of Chinese Academy of Sciences, beijing 100049, China 3.beijing Climate {3., beijing 100089, China 4 Department of Mathematics, Lanzhou University, Lanzhou 73.000, China 5.Shanghai Typhoon Institute, Shanghai 20003., China 6 Department of Atmospheric Sciences, Lanzhou University, Lanzhou 73.000, China 7 China Meteorological Administration Training {3., beijing 100089, China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China beijing Climate center Beijing China Department of Mathematics Lanzhou University Lanzhou China Shanghai Typhoon Institute Shanghai China Department of Atmospheric Sciences Lanzhou University Lanzhou China China Meteorological Administration Training center Beijing China

By adopting the idea of three-dimensional Walker, Hadley and Rossby stream functions, the global atmospheric circulation can be considered as the sum of three stream functions from a global perspective. Therefore, a m... 详细信息

关键词： three-dimensional decomposition of the global atmospheric circulation generalized Walker Hadley and Rossby stream functions existence and uniqueness vertical motion

national 2000' GPS control network of China

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Progress in Natural Science:Materials International 2007年第8期17卷 983-987页

作者： Yang Yuanxi~(1**) Tang Yingzhe~1 Chen Chuanlu~2 Wang Min~3.Zhang Peng~4 Wang Xiaorui~2 Song Lijie~5.Zhang Zusheng~6 (1.Xi'an Research Institute of Surveying and Mapping,Xi'an 71005.,China 2.Geodetic Data Processing center,Xi'an 71005.,China 3.center of Earthquake Analysis and Prediction,China Seismological Bureau,beijing 10003.,China 4.{3. Geomatics center of China,beijing 100044,China 5.Institute of Surveying and Mapping,Zhengzhou University of Information Engineering,Zhengzhou 45.05.,China 6.First Crustal Deformation Monitoring center,China Seismological Bureau,Tianjin 3.0180,China) Xi'' an Research Institute of Surveying and Mapping Xi'' an 710054 China Geodetic Data Processing center Xi'' an 710054 China center of Earthquake Analysis and Prediction China Seismological Bureau Beijing 100036 China national Geomatics center of China Beijing 100044 China Institute of Surveying and Mapping Zhengzhou University of Information Engineering Zhengzhou 450052 China First Crustal Deformation Monitoring center China Seismological Bureau Tianjin 300180 China

An accurately unified national GPS network with more than 25.0 stations,named"national 2000' GPS Control Net- work",signed the epoch 2000.0,has been established by integrating the existing six nationwide GPS networks of China set up by differ- ent departments with different *** paper presents the characteristics of the existing GPS networks,summarizes the strategies in the integrated adjustment of the GPS network,including functional model,stochastic model as well as the adjustment principle modifi- *** modifying the adjustment strategies according to the characteristics of the existing GPS networks and under the support of the IGS stations,the accuracy of the integrated national GPS network is greatly *** datum differences among the sub networks disappear,the systematic error influences are weakened,and the effects of the outliers on the estimated coordinates and their variances are *** is shown that the average standard deviation for the horizontal component is smaller than 1.0 cm,the vertical component is smaller than 2.0 cm,and the three-dimensional (3.D) position of geo{3. coordinates is smaller than 3.0 *** exterior checking ac- curacy for the 3.D position is averagely better than 1.0 cm.

关键词： GPS control network adjustment systematic errors robust estimation variance component estimation coordinate system

Aerosol retrieval over land by exploiting the synergy of TERRA and AQUA MODIS DATA

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Science China Earth Sciences 2006年第6期49卷 641-649页

作者： TANG Jiakui1, XUE Yong1,2, YU Tong3. GUAN Yanning1, CAI Guoyin1 & HU Yincui1 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101, China 2. Department of Computing, London Metropolitan University, 166-220 Holloway Road, London N7 8DB, UK 3. beijing Environmental Monitor {3., beijing 100044, China State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Department of Computing London Metropolitan University London UK beijing Environmental Monitor center Beijing China

Aerosol retrieval over land from satellite remotely sensed data remains internationally a difficult task. By using MODIS data, the Dark Dense Vegetation (DDV) algorithm aerosol distribution and properties retrieval over land has shown excellent competence. However, this algorithm is re-stricted to lower surface reflectance such as water bodies and dense vegetation, which limits its actual application, and is unable to be used for high reflective surface such as over urban areas. In this paper, we introduce a new aerosol retrieval model by exploiting the Synergy of TERRA and AQUA MODIS data (SYNTAM), which can be used for various ground surfaces, including for high reflective surface. Preliminary validations have been carried out by comparing with AERONET measured data, which shows good accuracy and promising potential. Further research work is undergoing.

关键词： aerosol retrieval, aerosol optical thickness, MODIS, TERRA, AQUA.

A New Approach to the On-Orbit Evaluation of Point Spread Function of Thermal Infrared Images With Applications to FY-2 satellite Products

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A New Approach to the On-Orbit Evaluation of Point Spread Fu...

Characteristics of vertical ozone distribution in the lower troposphere in the Yangtze River Delta at Lin'an in the spring of 2001

作者： Qiang Guo,Changjun Yang,and Caiying Wei the national satellite Meteorological center,China Meteorological Administration,{3. 100081,China,the Key Laboratory of Radiometric Calibration and Validation for Environmental satellite,China Meteorological Administration,{3. 100081,China

Spatial characteristics of thermal infrared(TIR) images are generally described by image-derived point spread function(IDPSF) for sampled imaging *** investigators working on IDPSF on-orbit evaluation focus on visible and near-infrared images and pay little attention on TIR ones,the reason of which lies on the fact that the assumption of an observed target with an ideal step profile is not suitable for TIR band. A new approach for TIR images is proposed here based on a more common slope-profile model,where the transition features, i.e.,the sample number(N) and the beginning position of slope interval,are extracted from the observed *** results show that the estimation performance will be increased, with lower noise level as well as higher system modulation transfer function value at half of normalized spatial frequency(MTF) or smaller *** a good performance system with noise squared-root variance(SRV) no more than 1.0 count and MTF between 0.3.and 0.4,the relative error between simulated and estimated MTF\s is less than 20%.The IDPSF of FY-2C satellite TIR band is estimated,and the derived MTF0.5.is properly close to on-ground testing *** image quality of FY-2C TIR band has been improved by using Wiener filtering and the estimated IDPSF,which eventually benefits the cloud detection product with more detectable low fractus and increased detection accuracy by about 1%in *** a step-profile target as a special case of this model,the proposed approach is also suitable for visible and near-infrared images.

关键词： Index Terms—Infrared imaging optical image processing optical transfer functions.

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Science China Earth Sciences 2005年第9期48卷 1519-1528页

作者： ZHENG Xiangdong1, CHAN Chuenyu2, CUI Hong2, QIN Yu3. CHAN Loyan2, ZHENG Yongguang3.& LEE Yusiang2 1. Chinese Academy of Meteorological Sciences, beijing 100081, China 2. Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Hong Kong, China 3. Department of Atmospheric Sciences, Peking University, beijing 100871, China Chinese Academy of Meteorological Sciences Beijing China Department of Civil and Structural Engineering Hong Kong Polytechnic University Hung Hom Hong Kong China Department of Atmospheric Sciences Peking University Beijing China

We analyzed vertical distributions of ozone (O3. in the lower troposphere (< 5.km above ground) at Lin’an (119.75.E, 3..3.°N), Zhejiang Province using electrochemical concen- tration cell (ECC) ozonesonde data obta... 详细信息

We analyzed vertical distributions of ozone (O3. in the lower troposphere (5.km above ground) at Lin’an (119.75.E, 3..3.°N), Zhejiang Province using electrochemical concen- tration cell (ECC) ozonesonde data obtained from February 21 to April 13. 2001. The results showed that the vertical O3.distributions are controlled by metrological conditions and the char- acteristics of O3.profiles are related to those of wet bulb potential temperature and wind field. O3.below 2 km showed that the strongest variability and enhanced O3.mixing ratios were associated with easterly winds that blow pollutants from the upwind source region of the Yangtze River Delta (YRD) region. Vertical O3.profiles below 5.km can be grouped into 5.categories: (1) peak mixing ratio type, (2) well-mixed type, (3. layered-structure type, (4) episodic pollution type and (5. alti- tudinal increasing type. Vertical distributions of O3.affected by regional transport of polluted air masses were investigated. Transport of polluted air from high latitudes of northern China, ac- companying subsiding motion of air and stagnant atmospheric conditions are important factors that lead to high mixing ratios of O3.at Lin’an. The stagnant atmospheric conditions associated with a continental high pressure system and pollution plume transported from the YRD and cen- tral-eastern China also lead to regional accumulation of O3.and high O3.mixing ratio at Lin’an. Long-range transport of O3.and pollutants from the Pearl River Delta in South China and in-situ O3.formation also resulted in elevated O3.mixing ratios at around 1 km altitudes and layered O3.distribution in the lower troposphere.

关键词： vertical ozone distribution, lower troposphere, Yangtze River Delta, Lin'an.

Three-dimensional calculations of the currents in the Huanghai Sea and East China Sea during June of 1999

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Acta Oceanologica Sinica 2003年第3期22卷 333-349页

作者： Huiqun Wang, Yaochu Yuan, Yonggang Liu, Mingyu Zhou Second Institute of Oceanography, State Oceanic Administration, Hangzhou 3.0012, China. E-mail: wanghq@sio. zj. edu.cnKey Laboratory of Ocean Dynamic Processes and satellite Oceanography of State Oceanic Administration, Hangzhou 3.0012, Chinanational center for Marine Environmental Forecasts,{3., China Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China Key Lab. of Ocean Dynamic Processes Hangzhou 310012 China Natl. Ctr. Mar. Environ. Forecasts Beijing 100081 China

Based on the wind and hydrographic data obtained by R/V Xiangyanghong 14 during June of 1999, the currents in the Huanghai Sea and East China Sea are computed by the three dimensional non-linear diagnostic, semidiagnostic models and prognostic in the a coordinate. The computed results show that the density and velocity fields and so on have been adjusted when time is about 3.days, namely the solution of semidiagnostic calculation is obtained. In the northwest part of the computed region, the Huanghai coastal current flows southeastward, and then it flows out the computed region south of Cheju Island. In the west side of the southern part of the computed region, there is other current, which is mainly inshore branch of Taiwan Warm Current, and it flows cyclonically and turns to the northeast. In the region north of the above two currents, there is a cyclonic eddy southwest of Cheju Island, and it has characteristics of high density and low temperature. There is an offshore branch of Taiwan Warm Current in the west side of the Kuroshio, and it makes a cyclonic meander, then flows northeastward. The Kuroshio in the East China Sea is stronger, and flows northeastward. Its maximum horizontal velocity is 108.5.cm/s at the sea surface, which is located at the northern boundary, and it is 106.1 cm/s at 3. m level, 102.2 cm/s at 75.m level and 85.1 cm/s at 200 m level, respectively, which are all located at the southern boundary. Comparing the results of diagnostic calculation with those of semidiagnostic and prognostic calculations indicates that the horizontal velocity field agrees qualitatively, and there is a little difference between them in quantity. The comparison between the computed velocities and the observed velocities at the mooring station show that they agree each other.

关键词： non-linear diagnostic and semidiagnostic and prognostic models currents in the East China and Huanghai Seas

Hydrocarbon accumulation in network and its application in the continental rift basin

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Science China Earth Sciences 2008年第S2期51卷 88-100页

作者： PANG XiongQi1,2,CHEN DongXia1,ZHANG ShanWen3.HAO Fang1,LIU Zheng1,LIU KeYu3.SONG GuoQi4,WANG YongShi4,LUO XiaoRong5.& WU XiaoChun61 State Key Laboratory of Petroleum Resource and Prospecting,Chinese University of Petroleum,beijing 102249,China 2 Basin and Reservoir center,Chinese University of Petroleum,beijing 102249,China 3.SINOPEC Shengli Oilfield,Dongying 25.05.,China 4 CSIRO Petroleum,P. O. Box 113.,Bentley,WA 6102,Australia 5.Institute of Geology and Geophysics,Chinese Academy of Science,beijing 100029,China 6 China {5. Petroleum Corporation,beijing 100724,China State Key Laboratory of Petroleum Resource and Prospecting Chinese University of Petroleum Beijing China Basin and Reservoir center Chinese University of Petroleum Beijing China SINOPEC Shengli Oilfield Dongying China CSIRO Petroleum Bentley Australia Institute of Geology and Geophysics Chinese Academy of Science Beijing China China national Petroleum Corporation Beijing China

The concept of hydrocarbon accumulation in network was presented on basis of the overall analysis of the formation and evolution characteristics of the continental faulted basin and of the systemic re-search on the major controlling factors on the hydrocarbon accumulation. The hydrocarbon accumu-lation in network can be defined as hydrocarbon accumulation in a three-dimensional network system which is constituted by the hydrocarbon migration passages under multiple dynamics,following the hydrocarbon generation from source rocks. The research shows that the hydrocarbon accumulation in network is composed of four elements,i.e.,hydrocarbon source (source rock kitchen),hydrocarbon accumulation terminal (trap),network pathway connecting source and terminal (transporting system),and network potential driving hydrocarbon migration in the network pathway (migration dynamics). Compared with other networks,hydrocarbon accumulation in network has three basic characteristics: the irreversible geological process of material and information flow in the network; the loss of material and information in the flow process in the network; the multiple dynamics in the flow process. Interac-tion of all the elements in the geological process can be called hydrocarbon accumulation in network. There are three basic models for hydrocarbon accumulation in network,that is,hydrocarbon accumu-lation in the network source area,hydrocarbon accumulation in the network pathway,and hydrocarbon accumulation in the network terminal. The key in the application of the hydrocarbon accumulation models in network in practice is to confirm the major accumulation stage and the function range of the four elements controlling the hydrocarbon firstly,to predict the profitable accumulation region by su-perposition of the favorable areas confirmed by four elements consequently,and to evaluate the oil-bearing property of the trap as well as confirm drilling targets. This paper takes the Dongying De-pression in the

关键词： continental rift basin hydrocarbon accumulation theory hydrocarbon network hydrocarbon accumulation in network Bohai Bay Basin

Sorption of Eu^(3.) onto nano-size silica-water interfaces

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Science China Earth Sciences 2005年第11期48卷 1942-1948页

作者： HU Ping1,2, YIN Xiulan3., ZHAO Linghu1 & LI Dien4 1. Department of Earth Sciences, China University of Geosciences, Wuhan 43.074, China 2. Northeastern Illinois University, Chicago, IL 60625. USA 3. China Institute of Geo-Environmental Monitoring, beijing 100081, China 4. Division of Chemistry, Los Alamos national Laboratory, Los Alamos, NM 875.4, USA Department of Earth Sciences China University of Geosciences Wuhan China Northeastern Illinois University Chicago IL USA China Institute of Geo-Environmental Monitoring Beijing China Division of Chemistry Los Alamos National Laboratory Los Alamos NM USA

The sorption of Eu species onto nano-size silica-water interfaces is investigated at pH range of 1―8.5.and the initial Eu concentrations (CEu) of 2 × 10?5. 2 × 10?4 and 2 × 10?3.M using fluorescence spectroscopy. The sorption rate of Eu is initially low, but significantly in-creases at pH > 4. For the initial CEu of 2 × 10?5. 2 × 10?4 and 2 × 10?3.M, the dissolved Eu spe-cies are completely sorbed onto silica-water interfaces at pH = 4.75. ~5.8 and 6.6, respectively, with the respective sorption densities of ~1.5. × 10?8, 1.5. × 10?7 and 1.5. × 10?6 mol/m2. The sorbed Eu species at pH 3., which is sorbed onto silica-water interfaces as an outer-sphere complex at pH 5. but may be sorbed as an inner-sphere bidentate complex at 5.3.+ and Eu(CO3.2? form in the solutions, and Eu(CO3.+ is dominant at pH = ~7.5. These ions may be sorbed onto silica-water interfaces as inner-sphere bidentate complexes or multi-nuclear pre-cipitates.

关键词： surface sorption, Eu3. species, nano-size silica, fluorescence spectroscopy, immobilization of toxic metals