A vortex ring model of large scale vortex structures of turbulent jets in crossflow

湍流横向射流大尺度涡结构的 涡 环模型

The nozzle structure and twisting principle of vortex spinning nozzle are both different from traditional air jet spinning and the appearance of the vortex yarn is similar to the ring spinning yarn .

喷气涡流纺的喷嘴结构和加捻原理均不同于传统喷气纺，喷气 涡流纱的外观类似 环锭纱。

For the vortex ring and wall oblique collision we mainly analyze the effect of initial angle on the evolution of vortical structures .

对于 涡 环与平板斜碰，着重探讨了涡环与平板初始夹角对涡结构演化的影响。

The vortex charge distribution in a thin mesoscopic superconducting ring is investigated by the phenomenological Ginzburg-Landau theory .

本文用Ginzburg-Landau理论研究在薄介观超导 环 中 的 涡旋电荷分布。

Physically at a special critical wave speed the flow may have a naturally periodical separated-reattached pattern with each wave trough capturing a stable vortex ring .

物理上看，在一个特定的临界行波速下会形成自发的周期性分离再附流，每个波谷的分离区捕获一个稳定的 涡 环。

Former deputy leaves on the cover can reduce the imports of the vortex impeller and particle loss of the wear and tear on the seal ring .

前盖板上的副叶片可以减少叶轮进口的 旋涡损失和颗粒对密封 环的磨损。

The range of yawing rate when turning left in hover is calculated where the tail rotor might get into vortex ring .

根据右侧飞试验结果，估算出样机悬停回转时尾桨处于 涡 环状态的偏航角速度范围；

Vortex ring is one of the most of fundamental and fascinating fluid mechanical phenomena .

涡 环是最基础也是最迷人的流体力学现象之一。

In a stratified fluid the free surface restrains the development of inter-nal waves resulting in little influence on the interaction between a vortex ring and the free surface .

在密度分层流中，自由表面的存在抑制了内波的发展，因而亦抑制了内波对自由表面的影响，使得密度分层对 涡 环与自由表面的相互作用影响不大。

According to the flight test it is clear that the most distinct cue of starting to get into vortex ring state is the appearance of heading oscillation and some kinetic regularity after sinking into vortex ring state are detected as well .

通过试飞，明确了直升机进入 涡 环状态的首要特征现象是机头开始出现航向摆动，摸清了直升机进入涡环状态后的一些运动规律。

The combination of the boundary integral method and a vortex ring model is used to simulate the process of jet impact penetration and the toroidal bubble rebound .

本文通过边界积分算法和 涡 环模型相结合的方式，成功地模拟了三维模型中射流撞击、穿透以及气泡的反弹过程。

The Gao-Xin criterion of vortex ring is compared with some overseas criteria .

将试验结果与国内外的 涡 环状态判据进行了对比。

The main contents of this Dissertation are organized as : ( 1 ) The changes of the degree of polarization of partially coherent vortex beams transmitted through a circular ring are investigated .

论文的主要内容为：（1）研究了 圆环衍射效应下部分相干 涡旋光束的偏振度变化。

A numerical study on the interaction between a planer shock wave and a vortex ring is performed by solving the unsteady Euler equations time accurately .

本文从非定常的Euler方程出发，进行了可 压缩 涡 环和平面激波相互作用的数值研究。首先，用数值方法建立了一种无粘可 压缩 涡 环模型；

The concept of transition region of vortex ring state is introduced and it can be sure that once helicopter gets into vortex ring state transition region rapidly pushing stick forward would make the helicopter recover from it timely .

本文首次提出了 涡 环状态过渡区的概念，指出当直升机进入过渡区时应立即顶杆增速，便可有效改出涡环状态。

The effect of the viscosity is mainly shown in the diffusion of vorticity and the generation of secondary vortex ring .

粘性的作用主要体现在涡量的耗散和新的二次 涡 环的产生；

Air jet vortex spinning is a new spinning technology which uses high-speed rotating airflow . In addition to the yarn strength slightly lower than ring spinning yarn other yarn properties are better than that of ring spun yarn .

喷气 涡流纺纱是利用高速旋转气流进行纺纱的新型纺纱技术，除纱线强力比 环锭纱稍低外，其他纱线特性均优于环锭纱。

To predict helicopter vortex ring state boundary is necessary for flight safety .

直升机 涡 环状态边界的确定对直升机飞行安全具有重要意义。

Also we investigated the influence of the vortex precession by variation of the width of the ring .

同时我们研究了 环宽度对 涡旋核的进动的影响， 涡旋核进动半径随着 环宽度的增大而减小。

The results show that : according to the axial direction the spray structure of flash boiling spray can be classified into follows : spray initial core region ; main body region of flash boiling spray ; vortex ring formation region .

结果发现：按照喷雾轴线方向，闪急沸腾喷雾的结构可以分为喷雾初始核区，闪急沸腾喷雾的主体区和 涡 环形成区。

In this paper the subsonic unsteady aerodynamic performance of a noncoplanar wing-tail combination can be computed on condition that the velocity potential function of unsteady vortex ring is taken as an elementary solution and the method of time history ( MTH ) is used .

本文以非定常 涡 环速度势函数为基本解，应用时间历程方法，计算非共面机一尾翼组合体的非定常气动力性能。

In this paper the helicopter tail rotor vortex ring has been calculated and analyzed according to the result of the rightward level side flight test of the sample helicopter .

根据样机右侧飞的飞行试验，对尾桨 涡 环现象进行了计算分析；

Shedding Comparison and Analysis of Fabric Woven by Air Vortex Yarn and Ring Yarn

涡流纱织物和 环锭纱织物的落毛对比分析

For the thin vortex ring the secondary ring moves around the primary ring after it separates from the wall .

对于薄 涡 环，二次涡在壁面生成后环绕主 涡环运动。

Air-jet vortex spinning yarn has the structure similar to that of ring yarn but MVS yarn has less hairiness good resistance to pilling and better moisture absorption and release .

喷气 涡流纱具有类似 环锭纱的结构，但毛羽比环锭纱大大减少，具有非常好的抗起球性能，纱体蓬松，吸湿及去湿快速。