数值分析

This paper introduces the food refrigerated theory and the basis of the current industry refrigerated developments in the situation; And then in the long cylindrical-shaped food heat conduction process and the mathematical model using the method of differential thermal conduction equations for discrete, Programming come through long cylindrical-shaped food cooling process numerical solution; After further analysis of numerical solution of the test results; Finally, the impact of the cooling process food all relevant factors, such as moisture content, wind speed and temperature of the cooling medium for in-depth research, while comparing the different shapes of food to food cooling process.

本文首先介绍了有关食品冷冻冷藏的基础理论和目前冷冻冷藏行业的发展的发展概况；然后研究了长圆柱状食品热传导过程的数学模型并利用差分的方法对热传导方程进行离散，通过编程得出长圆柱状食品冷却过程的数值解；之后再分析解对数值解的结果进行验证；最后对影响食品冷却过程的各相关因素，如含水率、风速和冷却介质温度等进行了深入的研究，同时又对比了不同形状的食品对食品冷却过程的影响。

Fourth precision solution can be derived from two grid sets solution with a second precision central difference scheme by Richardson extrapolation. It reduces the amount of calculation. Uncertainty is determined from the discretization error analysis. A finer grid calculation is made to validate the extrapolation scheme.

对于2阶精度中心差分格式的2套网格数值解，用Richardson外推法可以得到4阶精度的解，其工作量比直接求解4阶离散方程的工作量减少许多；对于计算中的数值不确定度，用该方法分析了离散误差，并用逐次加密网格的方法探讨了外推法的合理性。

Using this method, the DSMC program is developed to simulate flows in transitional region around a sphere double cone and Apollo capsule, and the aerodynamic and thermal characteristics around the supersonic and hypersonic vehicles is investigated.

在此基础上建立了一套DSMC数值模拟程序，对球双锥和Apollo飞船在过渡区域流动进行了数值模拟，并分析了其过渡区域超音速、高超音速的气动力、气动热等问题。

Based on the theory of large eddy simulation and the method of VOF , the initial breakup process of fuel liquid jet, which eject from the nozzle exit at the time scale of micro-second level, is investigated. The mechanism of primary atomization is analyzed, and the initial breakup model of liquid jet is presented. By modeling and numerical simulation of atomization for a diesel nozzle under the given conditions, the initial umbrella-like spray shapes are obtained, which fits better with the experimental results. Meanwhile, the droplets secondary breakup process, such as leeward RT breakup, dumbbell-like breakup and droplets coalescence, etc. are exhibited visually.

基于大涡模拟LES理论和VOF方法，考察了燃油喷雾初始时刻即时间尺度为微秒级的液柱破碎过程，分析了初始破碎的机理，给出了该时间尺度下液柱初始破碎过程的模型；通过对一特定条件下的柴油机喷油器的建模和喷雾过程的大涡数值模拟，获得了液柱初始时刻"伞状头部"的喷雾形态，所得计算结果与相应的试验数据符合较好；数值模拟还直观地展现了液滴背风RT破碎、哑铃型破碎以及液滴的聚集融合等液滴的二次雾化过程。

Using this method proposed in this thesis, superplastic free bulging process of duralumin LY12CZ under an external electric field is analysed, both with the constant pressure and with the constant strain rate at the apex.

将此解析—数值混合分析法应用于LY12CZ铝合金在强电场中的超塑性自由胀形过程的数值模拟，其中包括恒定胀形压力和恒定应变速率两种情况。

In this paper,a numerical solution for radial journal bearings with liquid hydro-dynamic lubrication is analysed, numerical expressions for oil fiton pressure, bearing capacity , friction moment,and leakage at the bearing ends are derived,bearing capacity,flow rate, friction moment,and eccentric angle of the load under 14 different temperatures and 14 different load eccentricities are calculated.

采用数值法分析解算液体动压向心滑动轴承，推导了油膜压力、承载力、摩擦力矩和端泄流量等的数值表达形式，计算了14个不同温度点及14种不同偏心率下的承载力、流量、摩擦力矩、载荷偏位角，并通过AUTOCAD绘制了它们之间的影响曲线。认为偏心率及油温对承载力影响很大，设计时应加以限制。

Then, we use the empirical data to estimate the parameter. Next, we use the estimated parameter values to calculate the elasticity of substitution and flexibility and come to some preliminary conclusions.

然后，利用所得的经验数据估计出要求得的参数值，并用估计出的参数值计算替代弹性值和弹性值，分析这些数值并得出结论。

The thecretical analysis is done for the problems of the integral initial values, the accumulated error and the excursive error induced by numerical integrals. It is found that these errors possess characteristics of lower frequencies and they can be treated as the low frequency noise.

针对积分初值、数值积分积累误差和数值积分引入的偏移误差进行了理论分析，得出此类误差均具有低频特性的性质，可作为信号低频噪声进行处理。

The paper introduces some researches, such as a new method to calculate the added mass for the seismic analysis of the fuel assembly in fast breeder reactor, simulation on the vortex shedding of double heat exchange tubes in a steam generator, simulation on the vortex shedding caused by the cross -flow over plates in a fuel assembly of an advanced reactor, the research on the impacting phenomenon of the free-surface on the vessel head in a storage tank as the main vessel of the China Experimental Fast Reactor shaken by the earthquake, and the researches on the solution of the liquid sloshing by moving particle semi-implicit and the scattering phenomenon caused by sloshing, and so on.

本文介绍华北电力大学在该方面的一些研究进展，例如，快堆燃料组件抗震分析新的流体附加质量计算方法研究；蒸汽发生器换热管双管漩涡脱落的数值模拟；一个先进堆燃料组件平行板上流动引起的漩涡脱落数值模拟；由地震引起的自由表面对快堆主容器冲击现象的研究；移动粒子法求解液面晃动及晃动引起离散现象的研究等。

The computation results agree with the experiment results very well. The muzzle flow field of an artillery with a muzzle brake is also simulated. The main characteristics and the mutual relations of shock waves in the muzzle flow field are obtained by the simulation. On the basis of the simulation results, the influences of the brake holes on the muzzle brake capabilities are analyzed.

对某口径火炮带有制退器的膛口流场进行了数值模拟，其结果反映了制退器内外流场的主要特征和冲击波波系之间的相互作用，在数值模拟的基础上分析了3排侧孔对制退器性能的影响。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。