查询词典 numerical system

The interaction between the foundation and soil is taken into account in the numerical method, which can simulate the actual working mechanism of the dynamic equipment foundation and circumambience soil. Thus, the numerical method has the advantage of more accuracy and reliability over the specification method based on the single mass model.

数值方法考虑了基础和地基的相互作用，更能模拟动力设备基础及周围土体的实际工作机制，较基于单质点模型基础之上的规范方法有更高的精确性和更大的可信度。

In this dissertation, EISCAT radar observations and computer numerical simulation methods are involved to study the climatologic characteristics of polar ionosphere and their mechanisms, as well as the polar ionospheric responses to magnetospheric particle precipitation and convection electric field. Then, with the help of the numerical computation, the EISCAT data are employed to invert the energy spectra of auroral precipitating particles and their responses to magnetic storms and substorms.

本文联合利用EISCAT雷达数据和计算机数值模拟手段，以雷达探测数据为基础，数据分析和数值模拟、理论研究相结合，研究了极区电离层气候学特征与机制，磁层粒子沉降和对流电场对极区电离层的影响，并利用雷达数据反演极光沉降粒子能谱特征及其对磁暴和亚暴的响应。

Marc this paper carried out a finite element numerical simulation on the forming process of cold extruding for the starlike sleeve of constant speed cardan joint of car. The interrelated technological problems of numerical simulation were discussed in detail, the variation curve of extruding force during the course of loading, the cloud chart, which varies along with time, of temperature field distribution of workpiece, the equivalent plastic strain cloud chart of workpiece and the stress distribution cloud chart of diem inner ring were obtained thus explained fairly nice the reason of fatigue damage of dies.

Marc对轿车等速万向节星形套冷挤压成型过程进行了有限元数值模拟，详细讨论了有关数值模拟技术问题，得出了挤压力在加载过程中的变化曲线、工件随时间变化的温度场分布云图、工件等效塑性应变云图及模具内圈的应力分布云图，较好地解释了模具疲劳破坏的原因。

In this paper, according to the basic principle of light– ray propagation, the elliptic cylinder lenses have been designed and used to collimate the semiconductor laser beam. With the computer simulation by use of Matlab, the numerical results are given. The numerical results indicate that the divergence angle of the collimating beam could be as high as 0.1mrad.

在本文中，针对现在对半导体激光器准直的要求作者基于利用柱透镜对半导体激光器光束准直的理论分析，设计了利用椭圆面柱透镜对半导体激光器进行光束准直的方案，对半导体激光器发出的光束经过椭圆面柱透镜的光路进行计算，并且利用Matlab对方程进行求解及计算机模拟得到最终结果。

Order Hilbert ill-conditioned linear equations were solved, and the relative error was less than 0.45%. Numerical experiments verified that the method was efficient compared with the efficient methods used commonly nowadays. Numerical experiments results showed that the conjugate vector base method was suited for solving large-scale ill-conditioned linear equations with fast convergence and high precision.

通过对5000阶的Hilbert方程组进行求解，结果的相对误差小于0.45%，并与当前普遍使用有效的方法进行了比较，数值实验结果表明，该算法适合求解大型病态线性方程组，且具有快速收敛，精度较高的特性。

At first, the velocity which is the outlet velocity of 2-D numerical model by using the VOF and κ~εmodel is used as the inlet velocity of the 3-D numerical model. The control equations of 3-D water and sediment movement are described in the orthogonal curvilinear coordinates, and the equations is segregated by using the Finite Volume Method.

以二维的水气两相流的VOF 模型结合雷诺时均法的κ~ε双方程模型进行水气两相流计算，得到稳定流场作为三维水沙计算的初始进口条件。

Keywords: Delay differential equation;Numerical method;Numerical stability

中文关键词：延时微分方程；数值方法；数值稳定性

This paper studies the main geometrical parameter such as angle, height, width, stagger and the upper width in dentation and trapezoid flow path, firstly, uses the single-phase numerical simulation of the computational fluid dynamics technique to analyse the influence of different geometrical parameter on discharge coefficient and flow state exponent of drip emitter. Secondly, uses the two-phases numerical simulation of CFD (1% sand content ) to analyse the influence of the above mentioned geometrical parameter on the contribution regulation of sand and anti-clogging performance. Thirdly, uses the PIV （ particle Tracking Velocimetry ） technique which can see the small-scale flow path to observe and test the trajectories and velocities of solid particles in labyrinth flow path, and analyses the basic factors which can influence the movement characteristic of solid particles and the flow state in flow path.

本文以齿形流道、梯形流道为主要研究对象，以流道转角、流道高，流道宽、偏差量及梯形流道上底宽为主要结构参数，首先应用 CFD 单相流数值模拟技术对不同结构参数灌水器流道水力性能进行模拟，分析了不同结构参数对流态指数和流量系数的影响，其次，应用 CFD 两相流（含沙量为1%）数值模拟技术分析了结构参数对含沙量分布规律和抗堵塞性能的影响，然后，应用 PIV 可视化测试方法测试了固体颗粒在流道内运行轨迹及速度，分析了影响固体颗粒运动特性及流道内流体流态的基本因素，最后，对上述流道结构形式通过模具加工及滴灌带试制，进行了标准化测试（ GB/T 17187-1997 农业灌溉设备滴头技术规范和试验方法与 ISO 标准 ISO /TC23 /SC18 /WG5N4短周期堵塞测试程序），测试结果验证了 CFD 模拟结果，并提出了迷宫结构流道灌水器的抗堵塞设计方法。

In order to analyze the influence of the center air pipe diameter change on the combustion effect, numerical modeling was applied to numerical calculation on the temperature field of such type of boiler,through which temperature field in five different schemes were obtained. In addition, the influence law of change of the diameter of the center air pipe on the temperature field was analyzed. The temperature of the nearly-back wall region takes on a firstly decreasing and then increasing change with the diametrical decrease of the central wind pipe.

为研究改变中心风管直径后的4层燃烧器对炉膛燃烧的影响，采用数值模拟的方法对该型锅炉炉内的温度场进行数值计算，得到5种不同方案下该型锅炉炉内的温度场分布，并分析了中心风管直径的改变对炉内温度场的影响规律，即后墙近壁区温度随着中心风管直径的减小呈现先降低后升高的趋势。

Application of FLAC and numerical differential to surface deformation observation;2. The formulas solving numerical differential and integral of discrete function arc deduced in this paper.

推导了三次样条插值在求解列表函数的数值微分与积分的公式，给出了余项估计，编写了用于求解数值微分与积分的通用程序，通过数值算例表明，三次样条在插值逼近中具有非常好的性质。

In the days of sailing vessels the crew were afraid they would be becalmed on the ocean.

在使用帆船的时代，船员们担心他们会因为无风而无法在海洋上航行。

As long as foreign donors pay the PA's salary bill, few expect a new intifada.

只要外国继续为巴权力机构的薪水买单，希望发动新暴动的人便寥寥无几。