数值
- 与 数值 相关的网络例句 [注:此内容来源于网络,仅供参考]
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In this thesis, I summarize the theoretical calculation method, applied scope and notice of siphonic drainage system, and point out the advantage of siphonic drainage system compared with gravitation drainage system. In the archetype experiment study of siphonic drainage tube, I adopt different tube diameter and different structural height to survey the drainage volume and press in different place. I observe various kinds of flow state, and get chief factors which influence hydraulic peculiarity of system as the tube diameter or structural height, and find out the relevance of factor to flux. I apply CFD Fluent software and adopt standard k-ε model and RNG k-ε model, then use finite volume method and second-order upwind scheme to discrete numerical model, while coupling numeration of velocity field and press is based on SIMPLE. In the numerical simulation of curved part of tube, siphonic drainage tube experiment system and multi-outlet siphonic drainage system, I make research on internal velocity and press of system in different project condition by changing the tube diameter of curved part, negative press value in tube export and improving the quantity of water gutter. This thesis first adopts a method of combining archetype experiment and numerical simulation to study the siphonic drainage system, test and verify the validity of experiment and numerical simulation, and makefurther study on system, it solves the problems of limited testing conditions, and has a logical results, it can provide a valid method for optimizing and designing the drainage tube-net system. The conclusion have referring value for study and design of siphonic drainage system.
本文首先对虹吸式排水系统理论计算方法、适用范围以及注意事项做出总结,并分析了虹吸式排水系统的优势;再对虹吸式排水管道进行原型试验研究,采用不同管径不同立管高度,对系统流量、管道压强进行量测,观察了各种工况下的流态,对其水力特性进行研究分析,找出影响水力特性的落差、管径主要因素以及与排水量的关系;进一步应用计算流体力学Fluent软件,采用标准κ-ε模型与RNGκ-ε模型,计算过程应用有限体积法和二阶迎风格式对数值模型进行离散,速度和压力的耦合采用SIMPLE算法,分别对系统弯管段、虹吸排水管道试验系统、多斗虹吸式排水系统进行数值模拟分析,通过改变管段弯头处半径、管段出口负压值、增加雨水斗数对不同工况下系统内部的速度和压力进行研究;本文首次采用结合原型试验与数值模拟相结合的方法,对虹吸式屋面雨水排水系统进行研究,试验与模拟相互验证,并进行拓展,很好地解决了虹吸式屋面雨水排水系统由于试验条件限制问题,结果正确合理,为排水管网系统设计和优化研究提供了有效的方法,对工程设计有较好的参考价值。
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To all project practicality, the introduction is given to the operational characteristics, the methods for calculation and the researching actuality of the tail tunnels with sloping ceiling underground hydropower stations the Three Gorges. This paper has discussed in detail the characteristic method being the same with the compressive flow and the Priessmann solution being the same with the free-surface-pressure flow. And how to deal with boundary conditions has been expatiated. Also hydraulic transient process of tremendous load fluctuation in the tail tunnels with sloping ceiling has been numerical simulated and the Fortran program for numerical simulation has been given. The paper gain the maximal press for tail end of the shell, the maximal rising rate of rotational speed of generating set, the maximal vacuum degree for inlet of the tail tunnels and so on under 11 kinds conditions of tremendous load fluctuation. These conditions include the design conditions, the check conditions and the superposition conditions. Finally, the computing results have been analyzed and summarized. The end chapter is the general comment of the whole-length content and the describing of the intending view of researching.
本文以三峡右岸地下电站尾水洞设计为背景,从工程实际出发,阐述了变顶高尾水洞的工作特性、使用范围及其研究现状;详细论述了适用有压流的特征线法、适用明满交替流的普里斯曼解法等数学模型;边界条件的给定和明满交替流的计算方法;用Fonran语言编制了数值计算程序,对三峡右岸地下电站变顶高尾水洞的大波动工况进行了数值模拟,分别得出了在设计工况、校核工况和叠加工况下蜗壳末端最大压力上升值、机组最大转速上升值和尾水管进口最大真空度等重要参数;对数值计算结果进行了详细分析并得出了有价值的结论;最后展望了今后水电站变顶高尾水洞的研究方向。
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A 550kV SF6 circuit breaker has been taken as an example, the gas blast flow in no-load breaking process has been simulated, the results show that the basic solution of Euler equation set derived is correct, which lays the foundation for developing the Boundary Element Method of numerical solution for the time-dependent compressible flow of fluid.
作为数值模拟实例,文中对550kV SF6断路器空载开断过程中吹弧气体流动规律进行了数值模拟,其结果证明文中导出的基本解是正确的,从而为进一步开发求解非定常可压缩气体流动的边界元数值计算法奠定了基础。
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Shule River project area is located in northwest China\'s Gansu province,Hexi Corridor,which is the largest agricultural crop production base of Gansu province and typically arid and semi-arid areas. There are characteristics such as scarce rainfall,the temporal and spatial distribution inequality,strong evaporation,fragile ecological environment,the limited quantity of surface water. Agriculture,the people\'s living and ecological environment are significantly dependent on the groundwater. Based on the collection and processing of regional hydrological and geological data and the groundwater monitoring data,using the numerical simulation,geostatistics theory and multi-objective evolutionary algorithm,this paper studied the monitoring and evaluation of groundwater resources from the three aspects: groundwater numerical simulation and prediction,groundwater spatial variability and distribution and optimization modeling and sloving of groundwater monitoring network. The main work and research lies:(1) Using Yumen-Tashi basin,Anxi-Dunhuang basin and Huahai basin as study area,this paper used modflow model to simulate groundwater flow of three areas.
本文在收集和整理项目区水文地质数据以及地下水监测数据的基础上,基于数值模拟、地统计学理论及多目标进化算法,从地下水数值模拟与预测、地下水空间变异与分布特征分析以及地下水监测网优化建模与求解三个方面展开了对项目区地下水资源监测与评价的研究,主要研究工作如下:(1)以项目区内的玉门-踏实盆地、安西-敦煌盆地和花海盆地为研究区域,在《河西走廊项目中期计划调整报告》规划条件下,基于modflow模型对地下水水流进行数值模拟,计算并生成了三个区域2007-2030年地下水埋深预测数据以及等值图。
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The symplectic schemes have the ability to preserve the global symplectic structure of the phase space for a Hamiltonian system. They have substantial benefits in numerical computation for Hamiltonian system, especially in long-term simulations.
辛算法正是保持Hamilton系统内在性质的一种新型数值方法,该算法在长时间的数值计算中,具有常见数值方法无可比拟的计算优势。
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Cm tensiometer is using relative number that represents a tension can be defined by its own weight tensiometer so that the depth of the screen and handlethe, tension values may be indicated on the disk, or from directly from contropanels on indirectly.
厘米压力仪就是用不绝对数值表现压力的一栽,是堵住压力仪自身轻量使丝网下沉的广度的数值来筹算,压力数值可从辅导盘上不直接获得,或者从把持盘上不直接获得。
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Using a one--dimensional differential thermocline model, we simulated the temperature and thermocline of Yellow and Bohai Sea.
本论文建立了黄渤海环流的三维斜压模式,进行了黄渤海三维环流的数值模拟研究,另外,用一个温跃层一维微分模式对黄渤海的温度及跃层现象进行了数值模拟,最后,建立了一个黄渤海温度及环流的数值模式。
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The restoring force, torsional effect and peak values(displacement, velocity, acceleration) at each floor during the shaking table test are also presented in the report. Finally, a numerical model of this steel structure is developed by Drain2D+ computer program. Model is proved by test result.
最后,以Drain2D+建立本试验结构之二维数值模型,根据试验过程中之不同结构形式所模拟之不同地震状况,进行动力分析,并与振动台试验结果做比较,可以验证此一数值模型的可靠性,并更进一步利用此数值模型求出其结构模态以及塑性铰产生的时机与顺序及其生成的位置。
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In which T k is the mean kinetic temperature; D H is the heat of activation, 83.144 kJ·mole 1 (unless more accurate information is available from experimental studies); R is the universal gas constant, 8.3144 × 10 3 kJ·mole 1 ·degree 1; T 1 is the value for the temperature recorded during the first time period, e.g., the first week; T 2 is the value for the temperature recorded during the second time period, e.g., second week; and T n is the value for the temperature recorded during the nth time period, e.g., nth week, n being the total number of storage temperatures recorded (minimum of 52 weekly entries) during the annual observation period.
公式中Tk代表平均动力温度;⊿H代表激活的热能,83.144KJ.mole-1(除非从试验研究中能得到更精确的信息);R代表气体常数,8.3144×10-3KJ.mole-1.degree-1;T1为第一时间段记录的温度数值,例如,第一周;T2为第二时间段记录的温度数值,例如,第二周;Tn为第n时间段记录的温度数值,例如,第n周,n为记录的贮存温度的总数(每周一次记录,在每年的监测周期内最小为52次)【注释:所有温度T,为绝对温度,单位为开尔文。
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Methods: We selected 71 patients with acute hemorrhagic stroke as the study group who were hospitalized within 24 hours after onset in the 1st 3rd 5th 7th 9th 11th 13th 15th day of hospitalization and prior to the usage of dehydrant. We selected 30 normal people as the control group. We collected the data of cerebrovascular hemodynamic index including cerebral blood flow and velocity, cerebrovascular resistance, cerebrovascular elasticity ,dynamic resistance and critical pressure for each patient . We compared the data between the study group and control group ,also we compared the data in the different time after disease onset and the data of affected side and non-affected side by using SPSS software.
选择急性出血性脑血管病患者71例为观察组,正常人30例作为对照组,观察组以发病时间为起点,分别在发病后第1、3、5、7、9、11、13、15天且在使用脱水药前行脑循环动力学检测仪检测获得脑循环动力学参数,包括血流速度、血流量、血管弹性指标,血管阻力、血管调节功能指标动态阻力及临界压力数值,对观察组和对照组的各项数值进行比较,及观察组在发病后的不同时间进行前后比较,且对患侧和健侧数值之间进行比较,所得数据使用SPSS软件处理。
- 推荐网络例句
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Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".
歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车,和一双合并为一移交&整个lotta爱&。
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This is Kate, and that's Erin.
这是凯特,那个是爱朗。
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Articulate the aims, objectives and key aspects of a strategic business plan.
明确的宗旨,目标和重点战略业务计划。