数值计算

The effects of cylindrical lens shape and the laser-fiber distance on relative coupling efficiency are also studied.

给出了一个计算980 nm泵浦激光二极管与柱形透镜光纤耦合角向容忍度的理论模型，并选择圆形的柱透镜光纤进行数值计算，得出了在水平和垂直方向上偏转加平移时的相对耦合效率及绕光纤轴向转动的相对耦合效率的数值计算结果并加以分析，同时也研究了光纤透镜的形状和激光二极管与光纤的间距对相对耦合效率的影响。

The numerical study is carried out for a KVLCC2 tanker. Firstly, for the ship in oblique motion in deep water, determination of the computational domain, check of the grid dependence and selection of the turbulence model in numerical simulation are investigated. The effectivity of the numerical method is validated by comparing the numerical results with experimental data published in literature and the experimental results obtained by oblique towing test in the towing tank of Shanghai Jiao Tong University.

以KVLCC2大型油轮为研究对象，首先对船舶深水斜航运动粘性流计算中计算区域的确定、网格依赖性的检验以及湍流模型的选取等问题进行研究，通过将本文数值计算结果与他人的试验结果和在上海交通大学拖曳水池进行的船模斜拖试验结果相比较，验证了本文数值方法的有效性。

The main works in this paper are as follows:(1). In this thesis, a new method, continuous linearization model, is constructed for the non-linear dynamic systems. The precision Duhamel integration solution for the linearization equation is also given from the theory of linear differential equation. The calculating results show that the new method can improve the calculation precision greatly. In fact, the truncation error is not limited by this method, it can arrive the precision according to the requirement.

本文的主要工作有以下几个方面：(1)由于非线性项的存在，使得多数情况下难以得到非线性动力方程的解析解表达式，目前常使用数值积分方法来求解非线性动力学方程的解，但常规计算方法的计算精度不很理想，本文提出了含Taylor展开项中高阶余项的非线性动力方程的线性化数值计算方法，构造了瞬态线性化方程，给出了Duhamel积分的表达式。

The outflow fields of a simplified fastback car were studied with numerical methods of different turbulence models and diflerent discretization scheme s with the CFD code STARCD.

以简化的直背式轿车模型为研究对象，以商用计算流体力学软件STAR-CD为工具，应用不同的湍流模型和离散格式对轿车外流场进行了数值模拟，通过与试验结果的对比，研究了湍流模型和离散格式对直背式轿车外流场数值计算精度的影响，同时对SIMPLE算法及其两种修正方法PISO和SIMPISO算法的计算精度进行了比较。

The method of calculation of fiber model numerical value that established steel tube to restrain a ferroconcrete to control curved component part, use in computation follow the addition of load and increase steel tube to be opposite ceaselessly the restrains effect method of core concrete, numeric computation result and test result be identical are good.

建立了钢管约束钢筋混凝土压弯构件的纤维模型数值计算方法，计算中采用随荷载的增加而不断增大钢管对核心混凝土的约束效应的方法，数值计算结果和试验结果吻合良好。

It is proved that numerical simulation is a efficiency method for researching the microbus s temperature field by compare the numerical simulation result with the experiment result.

通过计算和试验结果的对比分析，说明数值计算方法是研究微型面包车温度场的一种有效方法，采用数值计算方法可以比较精确的模拟微型面包车温度场的分布情况。

On the same time, numerical computed method is utilized to solve the normal distribution function for the precision of computer.

同时利用数值计算方法，对求解过程中正态分布函数的计算进行了适当的数值处理以满足计算方法的要求。

At the same time calculation of numerical value is a necessary link solving the linear system of equations, which is a very important question in calculation of numerical value.

数值计算是科学计算中的一个必不可少的环节，而在数值计算中，一类很重要的问题就是线性方程组的求解。

Chapter 3 introduces the research contents and the results of the model test about the Xiangjiaba tailrace tunnel with sloping ceiling.

本章根据物理模型的试验条件和试验工况进行相应的数值计算，即在数值计算中，输入的管道、机组特性等参数均为模型试验实测数据，程序根据模型比尺输出原型的计算结果信息，并与原型化后的模型试验数据分析比较。

The research result shows that the relative error between the calculation result and the measurement result is less than 9.034%.This numerical calculation method can be used to calculate and analyze the temperature field of the power train compartment body and can meet the needs of engineering applications basically.

研究结果表明，动力舱体温度场的计算结果与测试结果的相对误差小于9.034%，所使用的数值计算方法可用于动力舱体温度场的数值计算及分析，基本满足工程设计的需要。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。