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The theoretical development of internal flow of turbomachinery is then summarized in terms of separation theory, vortex dynamics and flow pattern.

然后分别从分离流动理论、涡动力学和叶轮机械流型三个层次介绍叶轮机械内部流动理论的发展；从平面叶栅、环形叶栅、动态试验和试验技术等方面回顾叶轮机械试验研究进展；从控制方程、数值方法、网格生成等方面综述叶轮机械数值计算研究方法、研究内容及成果等，并概括改善叶轮机械气动性能的方法和现状。最后对叶轮机械内部流动研究进行展望。

A conclusion was drawn that Momentum theory, Vortex theory and Generalized dynamic wake were practicable to get the general design parameters and loads, loads cycles of the rotor were the main vibration excitation, and good dynamic compatibility between rotor and tower is propitious to the well function of the wind turbine unit.

指出动量理论、涡流理论及自由尾涡理论模型是确定风电机组总体设计参数和载荷的依据；叶轮的周期性载荷是机组振动的主要激励，叶轮和塔架良好的动力学相容性有利于机组可靠运行。

Synthesizing the degrees of freedom of both rotor and helicopter body, and involving time derivatives of flap motion coefficient and induced velocity model derived from vortex theory, the governing equations of helicopter maneuvering flight are derived properly, with combination of kinematic equations and dynamic equations.

集旋翼和机体之自由度并计及挥舞运动系数对时间的导数和涡流理论的诱速模型，把运动学方程和动力学方程组合起来，从而导出了机动飞行的控制方程。

The geometry of three dimension vortex sheet of the sides of foil and its trailing were determined by the kinematic boundary condition.

针对三维舵存在的端部梢涡及其尾涡卷起的现象，提出了一种新的考虑端部梢涡卷起的三维短翼理论计算模型。

By means of the present model certain phenomena related to the nonlinear acoustic properties of an orifice, such as the roll-up of the shed vortex sheet and the forming of the Vena-Contracta are simulated. For a sinusoidal sound pressure, the time- history of the average velocity through the orifice is computed, and the nonlinear distortion of the velocity is examined by means of the Fourier decomposition.

依据此模型，对圆孔声学非线性效应的若干特征现象进行了数值模拟，如脱落涡层的卷曲，Vena收缩段的动态形成；在孔板前声压按余弦规律变化的情况下，计算了孔中平均速度的时间历程，并借助于Fourier分解分析了孔中平均速度的畸变情况。

Moreover, to prevent the vorticity from entering into the body, the concept of "residual vorticity" is introduced in the sense that partial circulation of the vortex sheet is remained at the boundary without being diffused into the flow field. Blobs very close to the wall are thus unnecessary.

为避免部分新涡泡太过接近边界，我们引入了「残留涡度」的概念，将离边界甚近之环量转为涡片形式留在边界上，以减少环量进入物体内部之误差。

To simulate the diffusion of the vortex sheet into the flow field as time goes on, Koumoutsakos' analytical solution is employed, in which an effective vorticity flux is derived and used for solving the vorticity diffusion equation.

而涡片之环量随时间扩散进流场之现象则藉由Koumoutsakos之理论，以边界上之等效涡度通量求解扩散方程式，得解析解后，再将之离散为边界附近之新涡泡。

The no-penetration boundary condition is satisfied by placing a vortex sheet along the boundary, which strength must be adapted to cancel the slip velocity on the boundary induced by all the other flow components.

本论文以Leonard之面积扩散涡漩法及Huang之涡泡分裂融合修正法为基础，开发一满足无滑移、无穿透边界条件之数值模拟工具。

To simulate the diffusion of the vortex sheet into the flow field as time goes on, Koumoutsakos' analytical solution is employed, in which an effective vorticity flux is derived and used for solving the vorticity diffusion equation. The solution is then discretized into blobs (called "-blobs") in the vicinity of the boundary.

而涡片之环量随时间扩散进流场之现象则藉由Koumoutsakos之理论，以边界上之等效涡度通量求解扩散方程式，得解析解后，再将之离散为边界附近之新涡泡。

Moreover, blobs may move too close to the boundary because of advection errors or other numerical errors. It may cause serious fluctuations in evaluating the strength of the vortex sheet. In order to reduce the fluctuations, these near-wall blobs are also manipulated in use of the concept of "residual vorticity". Finally, we apply the so-developed solver to a simulation of the flow past an impulsively started circular cylinder at different Reynolds numbers.

此外既有涡泡也可能因对流或其他数值误差造成过於靠近边界，因此我们也设计一专门处理过於靠近边界涡泡之方法，以其他计算元素取代这些涡泡，降低进入物体内部之环量，进而降低涡片强度计算上的扰动。

Salt is good, but if the salt becomes flat and tasteless, with what do you season it?

14：33 盐本是好的，盐若失了味，可用什么叫它再咸呢？

He reiterated that the PLA is an army of the people under the leadership of the Communist Party of China.

他重申，人民解放军是在中国共产党领导下的人民军队。