Cfx software is used to simulate flow fields of water cushion pool . contour stream line , vortex and kinetic energy in water cushion pool are found and offered as visualization form . the results of numerical simulation and piv are analyzed and compared in this paper 使用数值软件( cfx )对此水工实验模型的淹没射流流场进行了数值模拟，得到水垫塘内的速度场、等流函数线图，将这些计算结果以可视化结果的形式给出。
( 5 ) as torsion is increased , the anticlockwise secondary vortexes and the negative area of the stream function increase ; the axial velocity moves anticlockwise ( annular pipe ) or clockwise ( circular pipe ) ; the friction factor ratio finally reaches the value about 1 ( 5 )增大挠率，逆时针方向旋转的一二次涡和流函数的负值区域增大，轴向速度最大值的位置按逆时针（环形截面）或顺时针（圆截面）方向旋转，摩擦系数比最终趋向于1 。
The streamlines of the flow are obtained from an exact analytical treatment of the stokes equations by making use of finite element methods and complex function theory . based on the calculations , the formation and evolution of vortices in the flow are visualized 运用有限元方法,从斯托克斯方程,连续性方程和流函数方程出发,通过有限元离散、等参元映射、数值积分和牛顿迭代,得到有限元方程的精确数值解,利用后处理软件对得到的数值结果进行了可视化处理。
And then , the cavity flow is simulated , and the streamline and pressure contour at different reynolds number are plotted , the stream function and location of vortex centers are agree well with the previous results , which indicate the incompressible lattice bgk model is reliable 进而对方腔流的速度场和压力场进行了计算，绘制了不同雷诺数下的流线图及压力等高线图，得到的回流涡的位置和流函数的值和现有的数据十分吻合，表明本文不可压格子模型是可靠的。
In this paper , some characteristics of flow movement and sediment transport are analyzed by using the flume experiment data . the cross section of compound channel can be divided into four regions : the undisturbed region in main channel , the interactive region between channel and plain , the undisturbed region in flood plain and the boundary region . in the undisturbed regions , the distribution of longitudinal velocity along the depth has the feature of lograithmic . whereas , in the interactive region , the longitudinal velocity does not obey the logarithmic distribution law , but it can expressed as a revised logarithmic function by using a wake function . on the basis of the kinematic equation the velocity distribution of transverse velocity is obtained . in the boundary region , the longitudinal velocity obeys the law of parabolic distribution . furthermore , according to the simplified diffusion equation , the transverse distribution of sediment concentration in the interactive region is deduced . the analysis is in good agreement with the measured data 本文根据漫滩水流的运动特点，将漫滩水流的复式断面分为主槽平衡区、滩槽交互区、滩地平衡区及边壁区等4个区，并给出了各区宽度的经验公式.根据滩槽交互区垂线流速分布的变化特点，提出了附加尾流函数的对数流速分布公式.在简化水流运动方程和泥沙扩散方程的基础上，对滩槽交互区内垂线平均流速及含沙量沿横向分布进行了理论分析，提出了反映滩槽水流动量交换强度的横向涡量粘性系数及横向扩散系数的表达式，得到了漫滩水流垂线平均流速及含沙量沿横向分布的解析解，并与实测资料吻合较好
The concept of convection transport is proposed to " see " the nature of the convective phenomena . the ability to see is very attractive , for the engineers and customers are much convinced by their seeing . unified convection transport functions ( streamfunction , heatfunction and massfunction ) are derived from the governing equations to describe the fluid , heat and mass transport respectively 作者在对流控制方程的基础上定义了描述流体、热、质传输统一的对流传输函数(流函数、热函数、质函数) ，并分析了传输函数及其传输路径(流线、热线、质线)的基本性质。
Second , we discuss the influence of environmental referance potential temperture and thermal wind on mesoscale symmetric instability . we find the expression of disturbance stream function and criterion of symmetric instability by analytical method and conclude that change caused by environmental referance potential temperture with height and thermal wind make critical richardson number and disturbance critical half - wave length of symmetric instability larger , that is to say , they benefit the occurance of symmetric instability . third , we study nonlinear perturbation analysis of mesoscale vertical circulation and evolution equation by means of f - plane . non - hydrostatic balance and filiter model 第二，讨论了环境位温与热成风因子对中尺度对称不稳定的影响。运用解析的方法求出了扰动流函数的表达式和对称不稳定的判据，发现环境参考位温随高度的变化与热成风因子使得对称不稳定临界理查逊数及扰动的临界半波长都变大，这有利于对称不稳定的发生。第三，采用f平面、非静力平衡、滤声波模式，讨论了中尺度垂直环流非线性摄动分析及演变方程。
The theoretical model of dc electroosmotic flow field is built based on the forming principle of the pumping rate and pressure of electroosmoticflow micropump . the numerical values of electric double layer and electroosmoticflow field are solved by using vorticity stream funcion formulation and finity difference algorithm . it shows many factors influence the pumping rate such as electric field indensity , section area , section shape , the dielectric constant and the viscosity constant of flow 本文详细的综述了直流电渗流微泵的国内外研究状况,阐述了双电层和直流电渗流微泵的原理,研究了电渗流微泵流量与压强的产生机制,建立了直流电渗流流场的理论模型,并利用涡度流函数法和有限差分法得到双电层电势和电渗流流场数值解。
The nonlinear exponent is a function of the radial distance from the pumping well . the two - regime well flow problems being in the steady state . in the fourth chapter , the problems of two - regime well flow have been discussed concentrating on a kind of special seepage law 第四章对一种特殊的非线性渗流规律即充分紊流的情况，进行了全面、详细地讨论，推导出了该情况下井流问题的渗流速度、水头降深和井流函数的解析表达式，作出了些具有代表性的标准曲线。
