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1.
采用涡环栅格法并结合Hess-Smith方法,建立了一种计算任意三维物体绕流的源汇-偶极子复合奇点法,提出了蜗尾船型势流场的计算模型。对长江优秀船型东方红11号(DO11)及其外旋蜗尾改型进行了计算,结果表明:DO11外蜗改型船桨盘面处的周向和径向合成伴流计算结果与流场测量结果定性一致。  相似文献   

2.
为了提高叶轮机械设计工作的效率,将CAD技术与三元流计算结合起来,开发适合叶轮机械的CAD软件。以AutoCADR13/forWindows95为基础,用C语言开发了6条用于叶轮机械CAD的实用扩展命令,能够显示叶片形状,生成和显示用于三元流计算的网格及将三元流计算结果图形化处理,包括绘制流场矢量图和等值线图。全部扩展命令集成到AutoCAD中运行。生成图形与AutoCAD完全兼容。是叶轮机械三元流动计算有力的辅助工具。  相似文献   

3.
利用QCD求和规则,在忽略奇异海夸克效应近似下,计算了核子同位旋标量轴矢流耦合常数gA^s。在极化函数物非微扰部分,本文计算了∫0×1dxg1^(p)(x)的三胶子凝聚修正。在QCD修正的组合夸克模型中,分析了质子的自旋结构函数,并得到S夸克对gA^s的贡献。  相似文献   

4.
导管螺旋桨定常性能理论计算   总被引:11,自引:1,他引:11  
建立了计算导管螺旋桨在均流中的定常水动力性能的数值方法,螺肇桨用涡格法,导管用面元法分别计算,两者的相互影响则通过迭代计算加以考虑,为了减少计量量,螺旋桨对导管的诱导速率周向平均值,从而使导管周围的非定常流动简化为定常对称流动,应用本法地JD简易导管桨系列进行了计算,数值结果试验数据吻合良好。  相似文献   

5.
作用在直立桩柱上的破碎波浪力研究   总被引:1,自引:0,他引:1  
采用理论分析与实验相结合的方法,对现有的计算作用在直立柱体上的破碎波浪力的各种方法(莫里森公式、冲击一绕流法)特点进行了分析。提出了计算破碎波浪力的绕流一绕流一冲击法,并给出了计算实例。结果表明,用绕流一绕流一冲击法计算出的破碎波浪力比常规波浪力大约3倍,约为冲击绕流法的2倍。实验结果证实了此法的正确性。本研究可为新滩海海洋结构物的设计和现役结构的安全使用提供理论依据。  相似文献   

6.
为了防止矿井动力现象(矿山压力、冲击地压、煤与瓦斯突出、二氧化碳突出等),保障矿井安全生产,必须全面了解矿区地应力分布规律。本文首先介绍了矿山现场用空芯包体法测试地应力的方法、步骤及仪器。在此基础上,用大型非线性有限元结构分析的ADINA程序在微机上进行了地应力数值分析,并将计算结果用ADINA后处理程序绘成了图表,分析计算结果对矿山现场工作有指导意义。  相似文献   

7.
用非定常非线性涡格法计算螺旋桨尾流场预估非定常性能,并进一步计算了瞬变工况下螺钉性能,对DTNSRDC4381和4383桨的尾流场进行了校核计算,取得了理想的结果;对ITTC建议的轴承力校核计算的螺旋桨,在给定的伴流场条件下计算其非定常性能,与试验结果和其他的理论方法比较,结果令人满意,最后计算了DTNSRDC4118桨在变工况下性能变化过程,显示了该方法用于螺肇钉性能预估的前景。  相似文献   

8.
基于Denton对置差分格式,发展了径流式透平叶轮内部三元流动Euler方程的时间推进有限体积求解方法,并对一个车用增压器径流式透平叶轮的内部流动在多个工况条件下进行了计算分析,揭示了其内流规律,与准三元流动分析结果的比较表明:准三元流动模型由于抱略了流面厚度的变化,相应的流运输设计计算都有局限性。因而,对径流式透平叶轮应该采用全三元流动分析方法设计叶道,以求叶轮内流效率及透性能有较大幅度的改善。  相似文献   

9.
信元时延偏差(CDV)是ATM网内引起信元丢失的主要原因之一。文中系统地分析了固定速率业务(CBR)的CDV的相关特性,包括信元时延特性、复用后信元流的分布特性及CDV的影响与监控。采用固定速率业务与独立同分布的背景业务相叠加的FIFO离散排队系统,求出了稳态时CBR信元时延、复用后信元流分布的母函数和信元流分布的极限情况,然后以求得的信元流分布为输入,求出了有CDV的CBR信元流通过漏桶监控机制时的违例信元概率,并以随机业务的泊松分布为例给出了数值计算结果。  相似文献   

10.
用格子Boltzmann方法计算来流为水平剪切流的方柱绕流问题, 得到了在不同速度梯度条件下方柱绕流的流线和等涡线图. 发现在圆柱尾部形成两排涡, 当来流速度梯度较大时, 两排涡有很大的不同. 计算结果表明, 用格子Boltzmann方法计算剪切流的方柱绕流问题是可行的, 计算结果与理论分析相符.  相似文献   

11.
Based on the bi-cubic Bessel spline function method, we have inverted the present-day crustal horizontal velocity field and deformation field in China continent by combining with 410 GPS observations, 327 seismic moment tensors of earthquakes and fault slip rates in China and its neighboring areas, and considered the geological and geophysical parameters at the same time. The results reveal that the crustal movement mostly takes on compression in SN-NE direction and extension in EW-NW direction in China continent. The continent is rotating southeast and takes on a clockwise rotation image from the west to the east, particularly in the southeast of Tibet and Chuan-dian area. Different blocks have different deformation in China continent. The south China, Ordos and Northeast block have good integrity.The deformation in the western part of China is obviously stronger than that in the eastern part. The strong strains are focused on the Himalaya, east Tibet,west Tian Shan and Chuandian block etc. The deformation at the joint of blocks is stronger than that within the blocks. The China continent deformation not only has the strike-slip faulting and extrusion feature but also has the crustal shortening and thickening feature.  相似文献   

12.
Heat flow distribution in Chinese continent and its adjacent areas   总被引:1,自引:0,他引:1  
Using a compilation of 6980 heat flow measurements, we produce a new heat flow map for the Chinese continent and its adjacent areas. We develop an objective and integrated method to interpolate the heat flow data, taking into account both the uniformity within geological units and coherency of regional heat flow. The geologic units are outlined based on Zhang et al.'s active tectonic block model. Our heat flow model is presented in two formats: a contour map and a heat flow dataset with values on a 1 × 1° grid for the Chinese continent and its adjacent areas, reflecting detailed variations in some regions. Also provided is a resolution map which helps understand the reliability of the heat flow model. Our results reveal that (1) Heat flows in the eastern part of the Chinese continent are relatively higher than those in the western part except that in the Tibetan Plateau area. (2) Heat flows in the Ordos and North China blocks are around 60 mW/m^2, and are 50-55 mW/m^2 in South China except for the continental marginal sea regions. (3) Heat flow is the lowest in the Junggar Basin, only 35-45 mW/m^2, and is 45-55 mW/m^2 in the Tarim Basin. The results of this study provide an important dataset for studies on thermal and rheological structures of the Chinese continent and its adjacent areas.  相似文献   

13.
将我国大陆理工科高校学报与美国和港台地区的高校学报相比较,在稿件选用和编辑人员组成的办刊方式上,我国显示了各校自办学习报的独立性,美国显示了本校与外校联合办刊的联合性;在组织形式上,我国大陆高校学报编辑部的组织机构健全,显示了稳定性,港台地区的组织机构变动性大,显示了松散性。提出应改变我国大陆高校“各自办刊”一统全国的局面,创办一批在全国理工科高校联办的、专科性、代表国家水平的学报,使之进入国际期刊行列。  相似文献   

14.
Zircon SHRIMP dating of granite from Qaidamshan, NW China   总被引:4,自引:0,他引:4  
Zircon SHRIMP dating from Qaidamshan granite shows that the granite age is 446 Ma, similar to that of eclogite in the UHP belt. We think that both granite and eclogite may be formed at different stages during tectonic evolution of this area. Together with other studies we suggested that the collision of ocean and continent plates may occur at the early Caledonian in this area, forming the eclogite, and the collision of continent and continent plates at the late Caledonian, forming the Qaidamshan granite with the zircon SHRIMP age of 446 Ma.  相似文献   

15.
根据粘性流体动力学旋转圆筒间流动理论分析地球边界层湍流级串,并用于探讨中国大陆动力学问题。因最近135Ma以来地球自转减慢,印度大陆向北漂移和俯冲,以及太平洋整体逆时针旋转和澳大利亚Ω涡环拟序结构向内扫掠,从而形成了中国及邻区若干涡旋系。  相似文献   

16.
均衡响应函数法影响因素的模型分析   总被引:1,自引:1,他引:0  
均衡响应函数法是求取岩石圈有效弹性厚度值最常用的方法之一,但是在应用过程中存在诸多因素影响方法的适用性和可靠性.通过模型分析的方法对均衡响应法应用过程中存在的几个主要影响因素进行考察,从而为实际工作中数据的选择、处理和应用提供一定的依据.  相似文献   

17.
普通高校体育教师的心理及行为特征研究   总被引:3,自引:0,他引:3  
我国普通高校体育改革与发展的关键是体育教师队伍的建设。如何了解和掌握教师的心理状态,有针对性地做好工作,充分调动广大教师的积极性,保证教师队伍的稳定是教师队伍建设的关键所在。采用了问卷调查、专家调查、数据统计、心理分析等综合方法,对此问题进行分析研究,结果表明:体育教师队伍总体上讲心态活跃、稳定与不稳定因素共存。应对教师队伍的心理及行为特征这一问题给予高度重视,并采取措施加以解决。  相似文献   

18.
The Jurassic is a period of intensive accretion along the eastern and southeastern margins of the Asian continent. The emphasis of the present study is the review of the Jurassic prism structure of the Russian Far Eastern Pacific Asian margin and comparison with its equivalent in the Japanese archipelago. The Jurassic accretion processes and geodynamic evolution of the Paleo-Asian continent eastern margins are outlined in the paper. During this period, the different ages and different facies fragments of the Paleo-Pacific, such as abyssal plain, intraoceanic volcanic seamountains and oceanic plateaux, were accreted onto the eastern margin of the Paleo-Asian continent as a result of step-wise subduction of oceanic lithosphere. Together with ocean-margin terrigenous deposits (trench-fill turbidites), these paleooceanic fragments formed a thick tectono-sedimentary complex of the Jurassic accretionary prism, causing the size of the continent to be expanded by an increase along its eastern margin.  相似文献   

19.
The Jurassic is a period of intensive accretion along the eastern and southeastern margins of the Asian continent. The emphasis of the present study is the review of the Jurassic prism structure of the Russian Far Eastern Pacific Asian margin and comparison with its equivalent in the Japanese archipelago. The Jurassic accretion processes and geodynamic evolution of the Paleo-Asian continent eastern margins are outlined in the paper. During this period, the different ages and different facies fragments of the Paleo-Pacific, such as abyssal plain, intraoceanic volcanic seamountains and oceanic plateaux, were accreted onto the eastern margin of the Paleo-Asian continent as a result of step-wise subduction of oceanic lithosphere. Together with ocean-margin terrigenous deposits (trench-fill turbidites), these paleooceanic fragments formed a thick tectono-sedimentary complex of the Jurassic accretionary prism, causing the size of the continent to be expanded by an increase along its eastern margin.  相似文献   

20.
为了更全面地分析区域陆地水储量长期变化趋势,利用2002年4月—2017年6月近16年的重力恢复与气候实验(gravity recovey and climate explorer, GRACE)时变重力场数据反演中国大陆地区陆地水储量变化,并与全球陆地资料同化系统(global land data assimilation system, GLDAS)水文模型结果进行比较分析。同时,通过扣除季节性信号研究近16年来中国大陆地区陆地水储量的异常变化。研究结果表明:在2002—2017年间,中国大陆地区北方以减少为主,而南方以增加为主,其中青藏高原南部、新疆北部和华北地区减少趋势最为显著,并呈现出加速趋势。GRACE时变重力场和GLDAS模型得到的关于加速度项时空分布基本相符,加速度项与长期趋势项的结合更好地反演区域陆地水储量变化。  相似文献   

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