THE RESEARCH OF NATURAL THREE－DIMENSIONAL NUMERICAL MODEL FOR WATER－SEDIMENT TWO－PHASE FLOW AND SEDIMENT MOVING REGULARITY NEAR THE RIVER BOUNDARY

ＴＨＥ　ＲＥＳＥＡＲＣＨ　ＯＦ　ＮＡＴＵＲＡＬ　ＴＨＲＥＥ－ＤＩＭＥＮＳＩＯＮＡＬ　ＮＵＭＥＲＩＣＡＬ　ＭＯＤＥＬ　ＦＯＲ　ＷＡＴＥＲ－ＳＥＤＩＭＥＮＴ　ＴＷＯ－ＰＨＡＳＥ　ＦＬＯＷ　ＡＮＤ　ＳＥＤＩＭＥＮＴ　ＭＯＶＩＮＧ　ＲＥＧＵＬＡＲＩＴＹ　ＮＥ...     

AN IMPLICIT SCHEME FOR THE NUMERICAL SOLUTION OF THE TIMEDEPENDENT HEAD／DISK DYNAMICS IN HARD DISK DRIVER BY FINITE ELEMENT METHOD

ＡＮ　ＩＭＰＬＩＣＩＴ　ＳＣＨＥＭＥ　ＦＯＲ　ＴＨＥ　ＮＵＭＥＲＩＣＡＬ　ＳＯＬＵＴＩＯＮ　ＯＦ　ＴＨＥ　ＴＩＭＥＤＥＰＥＮＤＥＮＴ　ＨＥＡＤ／ＤＩＳＫ　ＤＹＮＡＭＩＣＳ　ＩＮ　ＨＡＲＤ　ＤＩＳＫ　ＤＲＩＶＥＲ　ＢＹ　ＦＩＮＩＴＥ　ＥＬＥＭＥＮＴ　Ｍ...     

NUMERICAL COMPUTATION OF THE DIFFUSION OF THE CONTAMINANTS AND THE FLOW FIELD OF SKEW DISCHARGES INTO A CHANNEL

ＮＵＭＥＲＩＣＡＬ　ＣＯＭＰＵＴＡＴＩＯＮ　ＯＦ　ＴＨＥ　ＤＩＦＦＵＳＩＯＮ　ＯＦ　ＴＨＥ　ＣＯＮＴＡＭＩＮＡＮＴＳ　ＡＮＤ　ＴＨＥ　ＦＬＯＷ　ＦＩＥＬＤ　ＯＦ　ＳＫＥＷ　ＤＩＳＣＨＡＲＧＥＳ　ＩＮＴＯ　Ａ　ＣＨＡＮＮＥＬＮＵＭＥＲＩＣＡＬＣＯＭＰＵ...     

A SEPARATED－LAYER FINITE ANALYTIC METHOD FOR NUMERICAL SIMULATION OF A THREE－DIMENSIONAL VISCOUS FLOW FIELD AROUND A SHIP STERN

ＡＳＥＰＡＲＡＴＥＤ－ＬＡＹＥＲＦＩＮＩＴＥＡＮＡＬＹＴＩＣＭＥＴＨＯＤＦＯＲＮＵＭＥＲＩＣＡＬＳＩＭＵＬＡＴＩＯＮＯＦＡＴＨＲＥＥ－ＤＩＭＥＮＳＩＯＮＡＬＶＩＳＣＯＵＳＦＬＯＷＦＩＥＬＤＡＲＯＵＮＤＡＳＨＩＰＳＴＥＲＮＬｉＴｉｎｇ－ｑｉｕ；Ｍｉａｏ...     

THE PREDICTION OF WATER AND SALT REGIME IN SALTAFFECTED AREAS BY NUMERICAL SIMULATION

ＴＨＥＰＲＥＤＩＣＴＩＯＮＯＦＷＡＴＥＲＡＮＤＳＡＬＴＲＥＧＩＭＥＩＮＳＡＬＴＡＦＦＥＣＴＥＤＡＲＥＡＳＢＹＮＵＭＥＲＩＣＡＬＳＩＭＵＬＡＴＩＯＮ￥ＺｈａｎｇＹｕ－ｆａｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＩｒｒｉｇａｔｉｏｎａｎｄＤｒａｉｎａｇｅ，Ｗｕｈａ...     

THE APPLICATION OF THE AVERAGING FINITE DIFFERENCE SCHEME IN THE SIMULATION OF SEPARATED FLOW

ＴＨＥ　ＡＰＰＬＩＣＡＴＩＯＮ　ＯＦ　ＴＨＥ　ＡＶＥＲＡＧＩＮＧ　ＦＩＮＩＴＥ　ＤＩＦＦＥＲＥＮＣＥ　ＳＣＨＥＭＥ　ＩＮ　ＴＨＥ　ＳＩＭＵＬＡＴＩＯＮ　ＯＦ　ＳＥＰＡＲＡＴＥＤ　ＦＬＯＷＴＨＥＡＰＰＬＩＣＡＴＩＯＮＯＦＴＨＥＡＶＥＲＡＧＩＮＧＦＩＮＩ...     

NUMERICAL SIMULATION OF THE TURBULENT FLUID FLOW AND PREDICTION OF INCIPIENT CAVITATION NUMBER ON ISOLATED SURFACE TRIANGULAR PROTRUSION

ＮＵＭＥＲＩＣＡＬＳＩＭＵＬＡＴＩＯＮＯＦＴＨＥＴＵＲＢＵＬＥＮＴＦＬＵＩＤＦＬＯＷＡＮＤＰＲＥＤＩＣＴＩＯＮＯＦＩＮＣＩＰＩＥＮＴＣＡＶＩＴＡＴＩＯＮＮＵＭＢＥＲＯＮＩＳＯＬＡＴＥＤＳＵＲＦＡＣＥＴＲＩＡＮＧＵＬＡＲＰＲＯＴＲＵＳＩＯＮ￥ＲｅｎＢｉ...     

A NEW METHOD FOR SOLVING TURBULENT VELOCITY CORRELATION FUNCTIONS AND ITS APPLICATION TO THE CHANNEL FLOW

ＡＮＥＷＭＥＴＨＯＤＦＯＲＳＯＬＶＩＮＧＴＵＲＢＵＬＥＮＴＶＥＬＯＣＩＴＹＣＯＲＲＥＬＡＴＩＯＮＦＵＮＣＴＩＯＮＳＡＮＤＩＴＳＡＰＰＬＩＣＡＴＩＯＮＴＯＴＨＥＣＨＡＮＮＥＬＦＬＯＷＬｉｎＪｉａｎ－ｚｈｏｎｇ；ＷａｎｇＹｕ－ｚｈｉ（Ｄｅｐａｒｔｍｅｎｔ...     

THE INFLUENCE OF THE SECONDARY NORMAL STRESS DIFFERENCE OF VISCOELASTIC FLUID ON ECCENTRIC CAPSULE FLOW

ＴＨＥＩＮＦＬＵＥＮＣＥＯＦＴＨＥＳＥＣＯＮＤＡＲＹＮＯＲＭＡＬＳＴＲＥＳＳＤＩＦＦＥＲＥＮＣＥＯＦＶＩＳＣＯＥＬＡＳＴＩＣＦＬＵＩＤＯＮＥＣＣＥＮＴＲＩＣＣＡＰＳＵＬＥＦＬＯＷ￥ＰａｎＤａ－ｌｉｎ（ＧｕａｎｇｄｏｎｇＩｎｓｔｉｔｕｔｅｏｆｏｆＴｅｃ...     

NUMERICAL SIMULATION OF THE EFFECT OF FILLET FORMS ON APPENDAGE－BODY JUNCTION FLOW

ＮＵＭＥＲＩＣＡＬＳＩＭＵＬＡＴＩＯＮＯＦＴＨＥＥＦＦＥＣＴＯＦＦＩＬＬＥＴＦＯＲＭＳＯＮＡＰＰＥＮＤＡＧＥ－ＢＯＤＹＪＵＮＣＴＩＯＮＦＬＯＷＬｉＤｉｎｇ；ＺｈｏｕＬｉａｎ－ｄｉ（ＣｈｉｎａＳｈｉｐＳｃｉｅｎｔｉｆｉｃＲｅｓｅａｒｃｈＣｅｎｔｅｒＰ．...     

NUMERICAL SOLUTION OF THE THREE-DIMENSIONAL ELASTOHYDRODYNAMIC LUBRICATION FOR HEAVILY-LOADED FINITE JOURNAL BEARINGS

A coupling of the finite element and the boundary element methods is applied to theanalysis of the three-dimensional elastohydrodynamic lubrication for heavily-loaded finite jour-nal bearings.An iterative scheme,which is used to overcome the difficulty of the convergence athigh eccentricity ratios,is provided in this paper.The scheme,which is called the weighted av-erage method here,is successfully carried out in the iterative procedures of a set of non-linear e-quations that is constituted by a two-dimensional Reynolds'equation,a viscosity-pressure equa-tion and three dimensional elasticity equations.The analysis yields the performance parametersand the minimum film thickness of finite journal bearings,which satisfy the elastohydrodynamicrequirements of realistic three-dimensional bearing geometries,under heavy loading.     

HYDRODYNAMIC AND ELASTOHYDRODYNAMIC STUDIES OF A CYLINDRICAL JOURNAL BEARING

In this article, the effect of the bearing elastic deformation on the performance characteristics of a cylindrical journal bearing is analyzed. The variety of simulation models covers hydrodynamic (HD) and elastohydrodynamic (EHD) lubrication theories. The Reynolds equations governing the flow in the clearance space of the journal bearing are obtained by considering the effect of mass transfer across the fluid film. The finite element method with an iteration scheme was employed to solve both the Reynolds equation and the three-dimensional elasticity equation representing the displacement field in the bearing shell. The converged solutions for the lubricant flow and elastic deformation vector are obtained. Dynamic characteristics of the journal bearing are computed for HD and EHD theories. Numerical simulation results show that the flexibility of bearing liner has a significant influence on the performance of a cylindrical journal bearing. Indeed, the elastic deformations of the bearing liner extend the pressure area in the bearing and increase the minimum film thickness. Although, dynamic coefficient, load capacity and attitude angle decrease.     

求解河网一维N—S非线性方程组的一种简化延拓法

随着计算能力的进步,河网中一维N—S方程应用越来越多,但数学上常用于求解N—S非线性方程组的拟牛顿法收敛域小,不能保证迭代收敛,对工程应用带来了一定的困扰。该文提出了一种仅进行边界控制的简化延拓法,可大幅拓展非线性方程组迭代求解的收敛域,同时能保持算法的简洁和较低的计算开销,经实例验证,方法可行。     

河网水力数值模拟中Newton—Raphson法收敛性的证明

Newton-Raphson迭代法以其收敛速度快的优点而常被用于求解非线性代数方程组，但对各种不同的问题其局部收敛性条件的证明往往是十分困难的。本文针对用Newton-Raphson迭代法求解河网数值模拟中所出现的非线性代数方程组的问题，证明了只要当时间步长取得足够小时， 迭代法的局部收敛性条件就一定可以满足，从而给出了Newton-Raphson迭代法在河网非恒定流计算中应用的一个理论基础。     

偶应力流体有限长径向轴承润滑特性分析

本文从具有偶应力的不可压缩流体基本方程出发,采用润滑层的通常假设,求得了流体速度的解析表达式,并推导了偶应力流体润滑的雷诺方程,把它应用于有限长径向滑动轴承的求解。通过数值计算得到了偶应力参数对有限长径向轴承的承载力、流量系数和摩擦系数的影响。     

Modelling of 2-D extended Boussinesq equations using a hybrid numerical scheme

In this paper, a hybrid finite-difference and finite-volume numerical scheme is developed to solve the 2-D Boussinesq equations. The governing equations are the extended version of Madsen and Sorensen＇s formulations. The governing equations are firstly rearranged into a conservative form. The finite volume method with the HLLC Riemann solver is used to discretize the flux term while the remaining terms are discretized by using the finite difference method. The fourth order MUSCL-TVD scheme is employed to reconstruct the variables at the left and right states of the cell interface. The time marching is performed by using the explicit second-order MUSCL-Hancock scheme with the adaptive time step. The developed model is validated against various experimental measurements for wave propagation, breaking and runup on three dimensional bathymetries.     

ACOUSTIC ANALYSIS OF HYDRODYNAMIC AND ELASTO-HYDRODYNAMIC OIL LUBRICATED JOURNAL BEARINGS

The purpose of the present paper is to investigate the effect of elastic deformation of bearing liner on the acoustic behavior of oil lubricated journal bearings.Analysis is performed for hydrodynamic(HD) and elasto-hydrodynamic (EHD) lubrications.Dynamic behavior and acoustical properties are investigated through an analysis of pressure fluctuation calculated from the Reynolds equation governing the flow in the clearance space of the journal bearing.This is solved numerically using the finite difference method with the successive over relaxation technique.In elasto-hydrodynamic lubrication,the finite element method with in iteration scheme is adopted to solve both Reynolds equation and the three-dimensional elasticity equation representing the displacement field in the bearing shell.The results show that the sound pressure level of the bearing is markedly influenced by the flexibility of the bearing liner,the viscosity of lubricant and the load applied to journal.HD analysis shows that the journal centre’s orbit,from a disturbed position,converges to the static equilibrium position faster than EHD lubrication.The results of the present paper could aid in the design of low-noise rotor-bearing systems supported by oil lubricated journal bearings.     

水电站水能迭代算法探讨

通过深入分析水电站水能计算迭代过程,总结了水能计算迭代轨迹的单向性规律,并充分运用一维搜索原理,提出了水位单向逼近-区间衰减迭代算法,不但能确保水能迭代计算的绝对收敛性,同时兼顾了收敛速度,实例应用表明,效果良好.     

Series solution of a natural convection flow for a Carreau fluid in a vertical channel with peristalsis

An analysis has been achieved to study the natural convection of a non-Newtonian fluid(namely a Carreau fluid) in a vertical channel with rhythmically contracting walls. The Navier-Stokes and the energy equations are reduced to a system of nonlinear PDE by using the long wavelength approximation. The optimal homotopy analysis method(OHAM) is introduced to obtain the exact solutions for velocity and temperature fields. The convergence of the obtained OHAM solution is discussed explicitly. Numerical calculations are carried out for the pressure rise and the features of the flow and temperature characteristics are analyzed by plotting graphs and discussed in detail.     

台阶形陆架上孤立波传播的数值模拟

为了研究孤立波在带有陡升台地的陆架上的传播,用MAC方法求解了二维纳维尔-斯托克斯方程。本文在以下几点,改进了东京大学提出的修正的网格标记法:1.给出交错网格的新的标号系统;2.推导出自由表面上非规则星的新的压力迭代公式;3.对流函数、压力和速度使用了三值悬旗;4.把一维Burgers方程的部分守恒形式扩展用于二维N-S方程。这些使得程序更简单和精确。计算结果证卖,物理上很好地解释了孤立波的传播,入射波分成了反射波和透射波,然后开始分裂、破碎。 本文计算结果与线性波理论的结果很一致,但后者不能给出波运动的过程。