查询词典 vortex

The southwest vortex restricted the development of the plateau vortex in some way at the early stage when it appeared in the lower atmosphere. When they were coupled longitudinally, the vertical difference caused by the different vorticity advections between the upper and lower levels excitated the updrafts under 500 hPa and strengthened cyclone vorticity, and then the positive vorticity at 500 hPa and 700 hPa increased by two times The change rate of positive vorticity facilitated the plateau vortex to move eastward.

分析表明：高原涡与西南涡涡心之间的纬向距离在5个纬度的时候，两者上升气流都在500 hPa以下，当两者继续东移，在经向上耦合的时候，二者同时得到发展，西南涡中心的上升气流达到300 hPa，而高原涡中心的上升气流突破200 hPa；西南涡在低层出现初期，在一定程度上制约了高原涡的发展，随着两者在经向方向发生耦合，上下涡度平流不同造成垂直差动，将激发500 hPa以下的上升运动与气旋性涡度加强，使得500 hPa与700 hPa涡心正涡度值的增大近 1倍。

The above problems are studied in this thesis. First, the implicit NND scheme with mix flux splitting method proposed by Zhang Hanxin that is first order accurate in time and second order in space is modified. The modified scheme keeps the characteristics of fast convergence and is second order accurate both in time and space. It can be capable of simulating the unsteacly flow. Second, the topological method founded by Zhang Hanxin is improved to study the characteristics of vortex near the singular point on its axis and the cross streamlines on the longitudinal section passing the vortex axis. On the basis of topological results, a program which visualises numerical results is made out. It can help us analyse the characteristics of vortex motion.

本文对上述问题做了研究：第一，在数值模拟方面，借助于张涵信提出的NND算法和混合通量法，我们将他建立的时间为一阶、空间为二阶精度的快速隐式算法推广为时间和空间均为二阶精度的算法，这样做保留了原格式收敛快的特点，而且能适用于真实的非定常流态的计算；第二，将张涵信的拓扑分析方法加以推广，研究了涡轴附近及破裂点邻域内流场的空间特征，并以这些拓扑分析结果为指导，研制了一套显示计算结果的软件，这一软件能很好地帮助我们分析流场的计算结果和旋涡演变的特征。

To calculate the pressure drop of cyclone must consider the tangential velocity. Researchers regarded inner vortex as quasi-forced vortex and outer vortex as quasi-free one before.

旋风分离器阻力损失的理论计算离不开切向速度分布，以往在切向速度的研究中，认为内涡旋是准强制涡、外涡旋是准自由涡。

The swirling flow inside the cyclone showed the Rankine vortex characteristics, i e, strong swirling vortex at the central region of the cross-section and weak swirling quasi-free vortex near the wall.

方形旋风分离器内的流动具有Rankine涡的特点，即中心部分为强制涡区，边壁附近是准自由涡区。

The main aim of this thesis is to study the performance of a vortex tube in room and low temperature ranges and to find out the mechanism of the energy separation of the vortex tube, as well as to obtain from the applications of a vortex tube in low temperature ranges.

本文的研究目的就是通过理论和实验两方面深入分析和研究涡流管的常温和低温特性，探求涡流管能量分离机理的内在规律，以便为涡流管在低温下的应用提供依据。

Some conclusions were drown: there were different sizes of vortex in the cyclone tube; in the inner vortex region the vortex microscal was small, and the energy dispersion rate was high.

这样，气流的脉动带动了颗粒的脉动，气相湍流的扩散同样引起固相颗粒的湍流扩散，而且不同尺度的气相湍流涡旋对不同粒径的颗粒所产生的影响也是不同的。

The development of vortex is studied with ZHANG Han-xin′s vortex analysis theory. In addition,the second vortex breakdown performance and the grid influence are discussed in this article.

结合张涵信的旋涡定性分析理论对旋涡的发展过程进行研究，此外，还对二次涡破裂现象和网格分布影响等问题进行了探讨。

The development of vortex is studied with ZHANG Han-xin′s vortex analysis theory. In addition,the second vortex breakdown performance and the grid influence are discussed in this article.

连合张涵信的旋涡定性剖析表面对旋涡的成长历程举行研讨，另外，还对二次涡碎裂表象和网格漫衍影响等题目举行了探究。

The research result cannot satisfy the need of engineering design.In this paper, according to practical liquid differential equation ,allowing for moving rule and characteristic of moving field of vertical vortex , simplifying N-S equation, I have studied the discipline of condition, velocity and pressure of vertical vortex and analyzed some theory solutions such as plain vortex solution and solution in axial direction.

本文从实际流体运动微分方程出发，结合立轴旋涡运动规律和流场特征，采用对称恒定性假设，简化N—S方程，研究了立轴旋涡的水流流态、速度与压力的分布规律，分析了若干理论解，如平面螺旋流解、轴向流解等。

The author established the axisymmetrical bubble with the vortex sheet and the vortex ring and established the three-dimension bubble with vortex ring respectively based on the achievements of the former researchers.

本文在总结前人研究成果的基础上，分别建立了轴对称涡面模型、涡环模型以及三维涡环模型。

More direct, directer ; most direct, directest

径直的，笔直的

Do you know how to use a chain saw?

你知道如何使用链锯吗？