Because the operation in water hydraulic valves is controlled by flow fluid and the pressure drop results from energy loss of flow fluid past valve channel , the flow state of fluid in valves becomes the most important factor for the operational property of valves 由于水压阀是通过控制流体流动来操作系统的，阀的压降也来自于流体流经阀道时的能量损失，因此阀内的流体流动状态就成为决定阀操作性能最为重要的因素。
A fluid - thermal - structure coupled analysis technique needs to be developed for advanced engine design . presently , fluid flow and heat transfer is mainly analyzed using finite volume method ( fvm ) and structural deformation is often solved by finite element method ( fem ) 由于历史原因,目前在流体流动和传热分析中广泛采用的是控制容积法,而在弹性变形的分析上采用的是有限元法,并分别发展了相应的工程应用软件。
The characteristic approximation is used to handle the convection part along the direc - tion of fluid namely characteristic direction to ensure the high stability of the method in approximating the sharp fronts and reduce the numerical diffusion ; the mixed finite element spatial approximation is employed to deal with diffusion part and approximate the scalar unknown and the adjoint vector function optimally and simultaneously ; in order to preserve the integral conservation of the method , we introduce the modified characteristic method 该方法对方程的对流部分沿流体流动的方向即特征方向离散以保证格式在流动的锋线前沿逼近的高稳定性，消除数值弥散现象；对方程的扩散部分采用最低次混合有限元方法离散、同时以高精度逼近未知函数及未知函数的梯度；为保证方法的整体守恒性，在格式中引入修正项
In this paper , oil reservoir fine description has been applied , and by study of reservoir , structure and fluid features , fluid units have been divided and new geology models have been rebuilt . then logging data have been reinterpreted and reprocessed and numerical modeling results have been used . on base of these work , the residual oil distribution feature and regulation in the fluvial facies sandstone in gudao oil field south region has been scientifically studied 本文主要运用油藏精细描述技术，通过储层、构造、流体研究，划分出流体流动单元，重建新的地质模型，在此基础上对测井资料进行了重新解释和处理，并运用数值模拟研究结果，对孤岛油田南区河流相砂岩油藏剩余油分布特征和分布规律进行了科学研究。
Under the assumption that the inner surface of stator sleeve and outer surface of rotor are smooth , taking the fact into account that the temperature of stator sleeve of evaporation cooling motor keeps almost the same , horizontal evaporation cooling motor is simplified as a physical model of two coaxial sleeves , with outer sleeve ( the stator ) holds still and keep at constant temperature and inner sleeve ( the rotor ) is rotating and heated 本文通过数值和实验手段研究了卧式蒸发冷却电机楔形气隙中的流体流动、传热现象。本文在定子套筒和转子表面光滑的假设下，针对蒸发冷却电机定子套筒壁面基本恒温的特点，将实际蒸发冷却电机简化为同轴套筒内筒加热旋转、外简静止定温的物理模型。
Main content in simulation is the spatio - temporal evolution of the set of descriptive variables characterizing tectonic mineralization state under coupling of various processes as following : ( 1 ) variables related to forming and property of ore - forming fluid , such as dissolution rate of minerals ( include metal minerals ) in rock , concentration and saturation of aqueous species in fluid , temperature , pressure , and ionic strength etc . ; ( 2 ) variables related to structural deformation and fluid flow , such as stress , deformation rate , fracture network , porosity , fracture permeability ; ( 3 ) variables related to precipitation and mineralization , such as nucleation rate of gangue and metal minerals , accumulation precipitation of various minerals , etc . ; ( 4 ) spatio - temporal coupling relation of various variables above , such as the coupling relationship between spatio - temporal evolution of fracture permeability and flow and focus of fluid and ore - forming 模拟的主要内容是在各种过程耦合作用下，以下描述构造成矿体系的主要变量的时空演化：与成矿流体的形成和性质有关的变量，如地层中矿物（包括成矿物质）的溶解速率、流体中各组分的浓度与饱和度、流体温度、压力、离子强度等；与构造变形和流体运移有关的各变量，如应力与变形速率、岩石孔隙度、构造（断裂）渗透率等；与沉淀成矿有关的变量，如矿物（金属矿物和脉石矿物）的成核速率、各矿物的沉淀量等；上述各有关变量间的时空耦合关系，如断裂渗透率时空演化与流体流动、汇聚和成矿的耦合关系等。
Based on prandtl ' s momentum transportation , this paper calculates in detail the physical quantities such as eddy viscosities , and ratio of eddy viscosity to motion viscosity , total stresses with respect to relative position in three regions of viscous sub - layer , buffer layer , and main turbulent stream for non - newtonian fluid flowing turbulently in ducts , which according to karman ' s three layer models and measurement of fluid parameters in evaluation apparatus , discusses the influence of polymer drag reduction on flowing properties of non - newton fluid , analyzes quantitatively principle of turbulent reduction phenomenon and condition of increasing reduction rate 摘要以普兰德动量传递理论为基础，按照卡门的三层模型，通过室内模拟环道用0号柴油及加入减阻剂在圆管内的流动参数的测定，计算了非牛顿型流体管内湍流边界层的层流内层、过渡层、湍流中心的涡流粘度，涡流粘度与运动粘度比、总应力随相对位置的变化等定量参数，探讨了高分子减阻剂对非牛顿流体流动特性的影响，对湍流减阻现象的机理与增大减阻率的条件进行了定量分析。
The finite element method ( fem ) has become an important means in modern engineering designs , which is used in many fields , such as structural stress analysis , deformational stiffness analysis , mechanic failure analysis , dynamic process analysis , heat analysis , electromagnetism filed analysis and so on 有限元素法已成为工程设计中不可或缺的重要技术手段，在大型结构作用力分析、变形分析、失效分析、动力学分析、传热分析、电磁场分析、流体流动分析等方面扮演着越来越重要的角色。
Simulation results for non - isothermal flow pass plate have been shown . the spatial correlations in a fluid subjected to an external temperature gradient have been computed by using cellular automata simulations of a simple lattice - gas model with temperature . but , this theory is found limitedly applied to mechanics 并给出了平板非等温流体绕流流动现象的模拟结果；通过采用一个含有温度的简化格子气模型，用细胞自动机方法，模拟计算了服从于外部温度梯度的二维流体中的平衡与非平衡空间相关函数，数值结果表明：该方法的计算结果和由涨落流体动力学理论的预言在是性上是完全符合的； bernsdorf等人用ca讨论在复杂障碍物情况时的流体流动问题。
