涡

Although the dispersion of particles with the Stokes numbers far less than or of the same order of 1 are insensitive to the changes of inlet velocity differences, the dispersion of particles with Stokes number much larger than the order of 1 are influenced by the coherent structures under U〓/U〓=α=0, where α=0 means the particles are released into the flow in stationary state.

在目前国内开展三维N-S方程大涡模拟还非常困难的情况下，本文以两相平面湍射流为对象，不采用流动对称性假设，成功地用大涡模拟方法预报了平面湍射流拟序结构的产生、发展及大涡的合并破碎全过程，和F.O。

This system can complete quickly,the realtime parametric design of turbojet,turbofan,turboprop and turboshaft engine and its parts.During designing the required information,data and structural graphics can be inquired interactively from Aeroengine Information Database and Structure Database.

该系统可以实现对涡喷、涡扇、涡轴和涡桨航空发动机部件图和总图的参数化实时设计，在参数化设计过程中提供发动机信息数据库、结构数据库的交互式查询，为设计提供所需的信息、数据和结构图形支持，可达到快速地生成供方案论证应用的各种航空发动机部件图、总图及各种信息，能快速实现多方案对比设计。

The formation of eddies in pipe flow and the characteristics of its velocity field and vorticity field are presened in this paper, based on experimental studies.

在试验研究的基础上，论述了有涡管流的产生条件及速度场和涡量场特性，给出了典型的流速分布并绘制了涡

The dimidiate frequency of early oil whirl was found clearly from HHT time-frequency spectrum, which magnified the parameter of oil whirl fault and provided information for early fault diagnosis.

该方法在早期油膜涡动中能够更加清晰地发现涡动二分频的存在，放大了涡动的故障特征，为早期故障诊断提供了方便。

Vortex lattice method is presented for calculating the loading distributions on all blades of propeller and hub which a number of small hyperboloidal quadrilateral panels are discreted.

螺旋桨采用离散涡环法，将桨叶表面和桨毂表面离散为一系列双曲四边形，在四边形网格中布置集中涡环和线源分布，根据物面条件建立方程得到涡和源汇分布的强度。

Based on the real observation data, forecast equitation or forecast model, the dynamics method such as divergence and vorticity calculation, real data correction, ascending and subsidence calculation was used to simulate the 4D field of divergence, vorticity and vertical velocity at different time, different range and different levels. The field was connected to 3D fields of insect trajectories, yielding the flying speed, direction, ascending area and subsidence. Thus the peak of immigratory insect could be timely monitored. A system of the peak of immigratory insect forecast was set up.

根据实际观测资料、数值预报方程或数值预报模式等输出的风场网格化处理结果，利用运动学方法、散度推算法、涡度推算法、实际资料订正法、升降法等对不同时间、不同范围、不同层次的四维散度、涡度和垂直运动速度场进行计算或模拟，将计算或模拟得到的散度场、涡度场、垂直运动速度场与昆虫迁飞的三维气流场联系起来，得到该类昆虫所具有的迁飞速度、方向、上升区和下降区，从而对昆虫的迁入峰进行实时预警。

We have got the following conclusions from the simulation in the thesis:(1) In even diameter hole, the tangental velocity has the characteristic of combination vortex; with the boundary of points for maximal speed, the insides is norm forced vortex, the outside is norm free vortex; the axis symmetry of tangental velocity is very well.

等直径工件孔内的螺旋流场，其切向速度分布具有组合涡的特点，以最大切向速度点形成的面为界，内部是强制涡，外部是自由涡，其轴对称性很好。

In this paper, The delta wing of Mach number 0.8 at an attack angle of 21. 8 degree is simulated by our program. Then, using the visualizing program, we map the figures of space streamlines, cross streamlines near the vortex axis, three dimensional vortex lines, cloud atlas for pressure and vortex and targer of particles.

在这一章里，我们先用所建立的计算软件数值模拟了来流马赫数为0.8、攻角为21.8°的三角翼的流场，之后以拓扑分析结果做指导，研制了一套数值显示流场、旋涡结构的软件，用该软件我们绘制了跨音速三角翼背风区涡轴附近截面流线、空间流线、三维涡量线、压力和涡量云图以及粒子屏痕图。

The results show that for a supersonic shear layer without reaction, a disturbance can make the shear layer become unstable, this results in one vortex or more than one vortex. The combination and seperation of vortex can intensify the mixing. But it is not easy for supersonic reacting shear layer with exotherm to become unstable with disturbance, and the effect duration is very long.

结果表明，对完全气体的超声速剪切层流动，一定的激励方式能使原先较为稳定的剪切层流动变得不稳定，产生单涡或多涡结构，发生多涡间的合并，使混合加剧；但对于存在放热现象的反应超声速剪切层流动，外加激励方式不易使流动从稳定变为不稳定，而且外加扰动的作用特征时间也较长，实际应用前景不乐观。

The reason was that the small scale eddies had other small scaleeddies that were carried by large scale eddies.

本文认为这是由于小涡中包含有大涡携带的小涡信号所致。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。