在W型火焰锅炉冷模中组织γ型气流的试验研究

提出了一种在Ｗ型火焰锅炉中组织燃烧工况的新方法－组织γ型火焰燃烧的方法，并在冷态模型试验台上作了试验研究，得出了不同工况的炉内γ型气流流场图谱，并对不同工况流场的主气流速度衰减规律和炉内气流充满度等进行了分析，最后，总结了γ型气流流场的配风规律，并分析了炉内结渣的可能性。     

炉膛喉口面积对W型火焰锅炉炉内空气动力场的影响

对珞璜电厂引进法国Ｓｔｅｉｎ公司３６０ＭＷ的Ｗ型火焰锅炉进行了冷态模化研究。采用热线风速仪对炉内流场进行测试,在此基础上研究了炉膛喉口面积对炉内空气动力场的影响规律,得出了在不同相对喉口面积下的炉内气流流场图,并对炉内的气流速度分布,气流充满度和平均有效动量流率等进行了比较与分析。研究表明,适当缩小炉膛喉面积,王方面有利于喷入炉内煤粉的着火和燃尽,另一方面有利于减小高温烟气对喉口和前,后拱及冷灰斗     

气体再燃燃烧器喷口流动特性冷态实验研究

以某350 MW锅炉为原型建立冷态模拟试验台,研究气体再燃技术中再燃气体和炉内旋转气流的混合程度及气体再燃条件下实验炉内的空气动力场,并采用标准k-ε湍流模型对其进行了数值模拟.结果表明,不同的再燃风速度对炉内的空气动力场有影响.再燃风速度过小时,再燃风偏离射流轴线较早,不能射入炉膛旋转气流的中心部位;而当再燃风速度过大时,导致再燃风射穿炉内旋转气流.以上两种情况均不能对炉内气流起到很好的覆盖效果,进而影响着再燃气体和炉内气体的混合程度.     

混烧锅炉富氧燃烧的数值模拟

富氧燃烧会对煤粉和高炉煤气混烧锅炉炉内的燃烧特性产生重要影响.以130 t/h煤粉和高炉煤气混烧锅炉为研究对象,采用Fluent流体力学软件,对助燃气体(O2/N2)在3种不同氧气体积百分数(21％,23％,27％)工况下煤粉和高炉煤气混烧锅炉炉内的燃烧过程进行数值模拟.模拟得到3种工况下:炉内的温度场分布,烟气流场特性,火焰长度.模拟结果表明:随着氧气浓度的增加,燃料着火速度更快,燃烧更稳定,出口烟温逐渐降低,炉内烟气流速逐渐减少,强化了炉内传热效果,提高了锅炉热效率.     

600 MW机组锅炉水平烟道气流特性试验

以某厂600MW四角切圆燃烧锅炉为原型建立试验台,在1∶20的模型上对炉膛上部、屏区烟道的气流流动进行了冷态试验研究,测量了锅炉水平烟道的速度偏差,得出不同工况下水平烟道流场的分布情况,分析了屏区气流偏差形成的原因,得出四角切圆锅炉出口气流的残余旋转是造成锅炉屏区气流偏差的主要原因,为降低炉内气流偏差提供了理论依据.     

六角切圆燃烧锅炉炉内空气动力特性的研究与应用

建立冷志空气动力场模化试验后,对不同燃烧器布置工况进行试验研究,了解六角切圆燃烧锅炉炉内空气动力特性,分析其对炉膛和受热面结渣的影响,并把研究成果应用于其200MW锅炉机组的改造中,对工程实际具有很大的应用价值。     

300MW机组直流锅炉调峰运行水冷壁安全性分析

用计算机辅助计算方法，以国产３００ＭＷ机组ＵＰ直流锅炉水冷壁为对象，在机组调峰运行过程中炉内火焰中心发生偏斜的非正常工况的热负荷分布情况下，对３００ＭＷ、２６０ＭＷ、２４０ＭＷ和２１０ＭＷ的不同机组负荷，计算水冷壁各管屏内工质的水力偏差和热偏差。并据此计算水冷壁管内工质的传热特性和管壁金属温度，以确定水冷壁发生爆管事故的条件。通过计算得出了不同机组负荷下所能允许的最大炉内火焰中心偏斜系数，为提出防止发生爆管事故的措施和机组的安全运行分析提供了根据     

600MW“W”型火焰锅炉炉内燃烧过程的数值模拟

为了分析"W"型火焰锅炉爆管原因,对某电厂某台600MW"W"型火焰锅炉在100%,75%和50%负荷下以及不同煤质情况下的燃烧过程进行数值模拟计算,研究不同负荷及不同煤质时锅炉炉内速度场、温度场的分布。研究结果表明:100%负荷和50%负荷下速度场和温度场比较对称,75%负荷下则出现明显的偏斜;在100%负荷下,火焰冲刷下炉膛的前后墙两端较严重;在50%负荷下,炉膛火焰中心有所下移,冷灰斗处温度较高;在75%负荷下,后墙火焰冲刷前墙严重,上炉膛温度偏高以致过热器温度过高,这些区域都容易引起受热面结渣和爆管。     

燃烧器反切对大容量切向燃烧锅炉烟气偏差影响的研究

对６００ＭＷ机组切向燃烧锅炉在原设计工况下以及燃烧器采用反切技术时炉内和水平烟道内流场进行了冷态模化试验,研究表明,燃烧器采用反切后,无量纲准则数ＸＪ是反映护内流场分布的重要指标,其值取１左右时,炉内流动稳定,水平烟道速度偏差最小。     

切向燃烧锅炉炉膛结构对烟道气偏差的影响

对引进型６００ＭＷ机组四角切向燃烧锅炉进行冷态模化试验,系统地研究了上部炉膛的拆焰角结构和炉膛高度对水平烟道内气流速度下均匀性的影响,通过对原炉膛的结构进行改进,提出了新的折焰角结构和炉膛高度,明显减小于水平烟道内气流速度场的不均匀性,为解决大容量四角切向燃烧锅炉水平烟道烟气偏差提供了有价值的试验数据,并为锅炉设计和改造提供了参考依据。     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.