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不规则颗粒随机分布区域的数值仿真算法

系统仿真学报 2010年第1期22卷 51-55页

作者：宋来忠彭刚姜袁三峡大学理学院宜昌443002 三峡大学水电土木学院宜昌443002

基于参数曲线的自由变形技术,对含有大量不规则形状的增强颗粒/孔洞并呈随机分布的多相复合材料,在细观层次上给出了二维情形下模拟区域中由椭圆(或圆)几何变形得到不规则颗粒/孔洞的快速生成算法和优化算法,使得每一增强颗粒/孔洞的轮... 详细信息

基于参数曲线的自由变形技术,对含有大量不规则形状的增强颗粒/孔洞并呈随机分布的多相复合材料,在细观层次上给出了二维情形下模拟区域中由椭圆(或圆)几何变形得到不规则颗粒/孔洞的快速生成算法和优化算法,使得每一增强颗粒/孔洞的轮廓线都有确定的形式统一的参数方程。以骨料为卵石或碎石的混凝土为例,给出了二维级配、投放比、总含量等可控制的随机混凝土数值试样。为进一步在细观层次上研究和确定混凝土的动力学性能提供了理论依据。

关键词：随机模拟细观层次复合材料不规则颗粒/孔洞

NON-DARCY’S SEEPAGE IN WATER-SILT FLOW PROCESS IN RIVERBED

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NON-DARCY’S SEEPAGE IN WATER-SILT FLOW PROCESS IN RIVERBED

第九次河流泥沙国际学术大会

作者： Junrui CHAI and Meng HEcollege of civil and Hydroelectric engineering china three gorges university yichang 443.02 china college of Hydroelectric engineering Xi’an university of Technology Xi’an 710048 china

＜正＞Non-Darcy （or non-linear） seepage in water-silt flow process in riverbed occurs in sand and gravel beds, near the draining holes and pumping wells, and when the hydraulic gradient is high. The theoretical and empirical laws for non-Darcy （or non-linear） seepage were systematically analyzed and summarized in this paper. By means of combining the theoretical and numerical solution methods, the 1 -D and 2-D non-Darcy seepage models were solved and were compared with the corresponding linear seepage solutions. It can be shown that the non-linear seepage law can not be approximated by the linear seepage law.

关键词： Water-silt flow Riverbed Non-Darcy seepage Nonlinear relationship

Numerical Simulation of a Complete Turbine

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Numerical Simulation of a Complete Turbine

第七届全国水动力学学术会议暨第十九届全国水动力学研讨会

作者： Jiang Ding-guo Dai Hui-chao (college of civil and hydraulic engineering, china three gorges university, yichang 443.02, china Yangtze three gorges Project Development Corporation, yichang 443.02)

＜正＞The design process of hydraulic turbines is analyzed in this paper. The study shows that a numerical flow simulation on only one component of hydraulic turbine doesn’t satisfy the design and the flow analysis of it. In the paper, the method to get 3-D turbulence flow through the whole passage of turbine with boundary conditions transfer between components was described. To verify the method is effective, a numerical simulation of TGP turbine was described. Modeling is accomplished by solving the N-S function. Based on the standard k-ε turbulence model, the control equation is discretized by finite volume method and SMPLEC method is applied to solve the equations. The result shows that the method can be used to improve and optimize the design of turbine and the study of its hydraulic performance effectively.

关键词： TGP hydraulic turbine hydraulic performance numerical simulation interface

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建筑结构的SMA被动振动控制方法

力学季刊 2003年第2期24卷 250-256页

作者：彭刚李黎唐家祥三峡大学土木水电学院湖北宜昌443002 华中科技大学土木工程与力学学院武汉430074

文章根据Robery K等研制的SMA中心牵引型耗能器的基本原理,设计出一种具有自我保护能力的新型耗能器,并建立了对应的力学模型。在此基础上,利用Brinson相变发展的本构模型从热力学第一定律出发建立了耗能器的热力学平衡方程式,为了探讨... 详细信息

文章根据Robery K等研制的SMA中心牵引型耗能器的基本原理,设计出一种具有自我保护能力的新型耗能器,并建立了对应的力学模型。在此基础上,利用Brinson相变发展的本构模型从热力学第一定律出发建立了耗能器的热力学平衡方程式,为了探讨耗能器在结构中的被动控制效果,文章以三层单跨框架结构为例建立了结构在耗能器作用下的动力学方程式。最后,文章分别对耗能器与框架结构进行了数值仿真计算。结果表明,耗能器的耗能能力随温度的升高而下降,通过温控器的调节或改变相变温度点,可以使耗能器处于最佳耗能状态;SMA耗能丝材愈短,在相同的耗能器行程下,丝材应变愈大,相变发展愈充分,耗能量愈大,但最大应变不能超过材料的最大可恢复应变;SMA耗能器对结构在地震作用下的动力响应具有较显著的抑制作用,位移的峰值衰减率约50％～70％。

关键词：形状记忆合金被动控制耗能器

Study on Ecological Problems of Cascaded Reservoirs and the Countermeasure

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Study on Ecological Problems of Cascaded Reservoirs and the ...

2011 World Congress on engineering and Technology(CET 2011)

作者： Kun Dong Huichao Dai Xianfeng Huang college of Water Conservancy and hydropower engineering Hohai university Nanjing china Xiuhua Peng college of Hydraulic & Environmental engineering china three gorges university yichang china

With the rapid development of cascaded reservoirs, a series of eco-environment problems have been produced, though the reservoirs have achieved great social and economic benefit in recent years. The impacts of cascade reservoirs operation on eco-environment have been generally analyzed, including the impacts on atmosphere, water, biology, river morphology, estuary, and reservoir geology. Some measures and methods are also put forward, such as perfecting rules and laws, consummating the control system and taking ecological operation. Through these measures, the eco-environment problems of river basin are believed to be solved to a certain extent.

关键词： cascaded reservoirs eco-environmental impact operation

MODELING UNCONFINED SEEPAGE FLOW USING three-DIMENSIONAL NUMERICAL MANIFOLD METHOD

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Journal of Hydrodynamics 2010年第4期22卷 554-561页

作者： JIANG Qing-hui DENG Shu-shen ZHOU Chuang-bing LU Wen-bo School of civil engineering Wuhan University Wuhan 430072 China State Key Laboratory of Water Resources and hydropower engineering Science Wuhan University Wuhan 430072 China

three-dimensional numerical manifold method for unconfined seepage analysis is proposed in this *** constructing hydraulic potential functions of the manifold element,the element conductivity matrix and the global simultaneous equations for unconfined seepage analysis are derived in *** algorithm of locating the free surface and the formula for seepage forces are also ***-dimensional manifold method employs the tetrahedral mathematical meshes to cover the whole material *** the iterative process for locating the free surface,the manifold method can achieve an accurate seepage analysis of the saturated domain below the free surface with mathematical meshes *** the shape of manifold elements can be arbitrary,the disadvantage of changing the permeability of transitional elements cut by the free surface in the conventional Finite Element Method（FEM） is removed,and the accuracy of locating the free surface can be ***,the seepage force acting on the transitional elements can be accurately calculated by the simplex *** results for a typical example demonstrate the validity of the proposed method.

关键词： three-dimensional seepage numerical manifold method free surface mathematical mesh manifold element

Influence on Fishes of Dissolved Gas Supersaturation Caused by High-Dam Discharging and Its Countermeasures

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Influence on Fishes of Dissolved Gas Supersaturation Caused ...

2011 International Symposium on Water Resource and Environmental Protection(ISWREP 2011)

作者： Wang Qing Dai Huichao Peng Xiuhua college of Hydraulic & Environmental engineering three gorges university yichang china Wang Yu college of Water Conservancy and hydropower engineering Hohai university Nanjing china

Based on the knowledge of the study achievements domestic and international and some representative projects in china, we study the generation mechanism of dissolved gas supersaturation （DGS） during high-dam discharging, discuss the relationships of DGS’s three key indexes （total dissolved gas, dissolved nitrogen and dissolved oxygen） and its varying characteristics downstream along the river, and analyze the influence on fishes of DGS. Through the analysis of the in-situ observation data, we found that among the three key indexes downstream, DO drop quickly, DN almost like TGP drop slowly;high-dam discharging has strong deadly influence on fishes living in surface waterthe closer （to the dam）, the heavier. Here, we also summarize and analyze the countermeasures （both engineering and non-engineering） and suggest that cascade hydropower stations operation could be an effective action to reduce the influence.

关键词： high-dam discharge dissolved gas supersaturation gas bubble disease solutions

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三次指数平滑法在古滑坡复活预报中的应用

水电能源科学 2010年第9期28卷 98-100页

作者：陈飞三峡大学土木与建筑学院湖北宜昌443002 三峡大学三峡库区地质灾害教育部重点实验室湖北宜昌443002

针对滑坡预报模型和方法存在的局限性,采用Matlab仿真工具建立了基于Hamilton原理的三次指数平滑法预测模型,预测了淹锅沙坝古滑坡未来复活的趋势。

关键词：三次指数平滑法古滑坡复活滑坡预报模型 Ancient Landslide Hamilton原理 Matlab仿真预测模型局限性沙坝工具方法

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黄龙滩电厂扩建工程进场边坡有限元分析

岩土工程学报 2013年第S2期35卷 202-206页

作者：郭永成李建林王兴霞三峡大学土木与建筑学院湖北宜昌443002 三峡大学三峡库区地质灾害教育部重点实验室湖北宜昌443002 三峡大学水利与环境学院湖北宜昌443002

简要地介绍了黄龙滩电厂扩建工程概况以及该工程进场边坡坍塌情况,指出维护该边坡稳定性要进行治理的必要性。根据工程卸荷特点和相关文献资料,绘制了边坡岩体卸荷量与变形模量的关系图。分析进场边坡的工程特点,采用了卸荷岩体力学理... 详细信息

简要地介绍了黄龙滩电厂扩建工程概况以及该工程进场边坡坍塌情况,指出维护该边坡稳定性要进行治理的必要性。根据工程卸荷特点和相关文献资料,绘制了边坡岩体卸荷量与变形模量的关系图。分析进场边坡的工程特点,采用了卸荷岩体力学理论与方法对该边坡进行有限元分析,分为初始应力场、边坡开挖、边坡开挖卸荷、边坡加固等4种工况进行计算,得出边坡变形的相关规律,运用卸荷岩体力学理论计算所得的最大水平和竖直位移比常规计算的位移值都要大,且其在各个剖面的变化规律基本是一致的。加固措施对边坡开挖面水平位移的约束不明显,但对开挖面附近区域的应力状态有较大的改善,利于边坡的稳定。研究结果可为边坡的加固设计提供参考。

关键词：扩建工程卸荷有限元位移