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951.
2d-axisymmetric of natural and forced convection in the melt of a Czochralski equipment has been performed. The influence of the flow on the shape of the interface has been studied. 相似文献
952.
A novel approach to the development of a code for the solution of the time-dependent two-dimensional Navier–Stokes equations is described. The code involves coupling between the method of lines (MOL) for the solution of partial differential equations and a parabolic algorithm which removes the necessity of iterative solution on pressure and solution of a Poisson-type equation for the pressure. The code is applied to a test problem involving the solution of transient laminar flow in a short pipe for an incompressible Newtonian fluid. Comparisons show that the MOL solutions are in good agreement with the previously reported values. The proposed method described in this paper demonstrates the ease with which the Navier–Stokes equations can be solved in an accurate manner using sophisticated numerical algorithms for the solution of ordinary differential equations (ODEs). 相似文献
953.
954.
A submerged turbulent plane jet in shallow water impinging
vertically onto the free surface will produce a large-scale flapping
motion when the jet exit velocity is larger than a critical one. The
flapping phenomenon is verified in this paper through a large eddy
simulation where the free surface is modeled by volume of fluid
approach. The quantitative results for flapping jet are found to be
in good agreement with available experimental data in terms of mean
velocity, flapping-induced velocity and turbulence intensity.
Results show that the flapping motion is a new flow pattern with
characteristic flapping frequency for submerged turbulent plane
jets, the mean centerline velocity decay is considerably faster than
that of the stable impinging jet without flapping motion, and the
flapping-induced velocities are as important as the turbulent
fluctuations. 相似文献
955.
This work reports a numerical study undertaken to investigate the dynamic response of a rotor supported by two turbulent flow
model journal bearings with nonlinear suspension and lubricated with couple stress fluid under quadratic damping. This may
be the first time that analysis of rotor-bearing system considered the quadratic damping effect. The dynamic response of the
rotor center and bearing center are studied. The analysis methods employed in this study are inclusive of the dynamic trajectories
of the rotor center and bearing center, power spectra, Poincaré maps and bifurcation diagrams. The maximum Lyapunov exponent
analysis is also used to identify the onset of chaotic motion. The modeling results provide some useful insights into the
design and development of rotor-bearing system for rotating machinery that operates at highly rotational speed and highly
nonlinear regimes. 相似文献
956.
Boundary layer stagnation point flow of Casson fluid over a Riga plate of variable thickness is investigated in present article. Riga plate is an electromagnetic actuator consists of enduring magnets and gyrated aligned array of alternating electrodes mounted on a plane surface. Physical problem is modeled and simplified under appropriate transformations. Effects of thermal radiation and viscous dissipation are incorporated. These differential equations are solved by Keller Box Scheme using MATLAB. Comparison is given with shooting techniques along with RangeKutta Fehlberg method of order 5. Graphical and tabulated analysis is drawn. The results reveal that Eckert number,radiation and fluid parameters enhance temperature whereas they contribute in lowering rate of heat transfer. The numerical outcomes of present analysis depicts that Keller Box Method is capable and consistent to solve proposed nonlinear problem with high accuracy. 相似文献
957.
泊松类型方程边界元解法 总被引:2,自引:0,他引:2
本文采用高阶拉普拉斯算子基本解将泊松类型方程的区域积分全部变换成边界积分,使计算问题的维数减少一维.通过斯托克斯方程的算例,表明本文所用的方法是有效的方法。 相似文献
958.
Rafael Cortell 《International Journal of Non》2006,41(1):78-85
This paper presents a study of the flow and heat transfer of an incompressible homogeneous second grade fluid past a stretching sheet. The governing partial differential equations are converted into ordinary differential equations by a similarity transformation. The effects of viscous dissipation and work due to deformation are considered in the energy equation and the variations of dimensionless surface temperature and dimensionless surface temperature gradient with various parameters are graphed and tabulated. Two cases are studied, namely, (i) the sheet with constant surface temperature (CST case) and (ii) the sheet with prescribed surface temperature (PST case). 相似文献
959.
960.
本文对可压缩流体力学高精度拉格朗日格式及其保正性质近年来的发展给出回顾与综述.文中分别介绍了一维、二维可压缩流体力学方程中心型拉格朗日格式的设计步骤,回顾了高精度拉格朗日格式以及高精度保正拉格朗日格式的研究进展. 相似文献