Home  About us  Contact
 

Curvilinear Co-ordinate System (curvilinear + co-ordinate_system)

Distribution by Scientific Domains
Engineering100%

Selected Abstracts

A moving-mesh finite-volume method to solve free-surface seepage problem in arbitrary geometries

INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 14 2007
M. Darbandi
Abstract The main objective of this work is to develop a novel moving-mesh finite-volume method capable of solving the seepage problem in domains with arbitrary geometries. One major difficulty in analysing the seepage problem is the position of phreatic boundary which is unknown at the beginning of solution. In the current algorithm, we first choose an arbitrary solution domain with a hypothetical phreatic boundary and distribute the finite volumes therein. Then, we derive the conservative statement on a curvilinear co-ordinate system for each cell and implement the known boundary conditions all over the solution domain. Defining a consistency factor, the inconsistency between the hypothesis boundary and the known boundary conditions is measured at the phreatic boundary. Subsequently, the preceding mesh is suitably deformed so that its upper boundary matches the new location of the phreatic surface. This tactic results in a moving-mesh procedure which is continued until the nonlinear boundary conditions are fully satisfied at the phreatic boundary. To validate the developed algorithm, a number of seepage models, which have been previously targeted by the other investigators, are solved. Comparisons between the current results and those of other numerical methods as well as the experimental data show that the current moving-grid finite-volume method is highly robust and it provides sufficient accuracy and reliability. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Numerical simulation of vortical ideal fluid flow through curved channel

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 11 2003
N. P. Moshkin
Abstract A numerical algorithm to study the boundary-value problem in which the governing equations are the steady Euler equations and the vorticity is given on the inflow parts of the domain boundary is developed. The Euler equations are implemented in terms of the stream function and vorticity. An irregular physical domain is transformed into a rectangle in the computational domain and the Euler equations are rewritten with respect to a curvilinear co-ordinate system. The convergence of the finite-difference equations to the exact solution is shown experimentally for the test problems by comparing the computational results with the exact solutions on the sequence of grids. To find the pressure from the known vorticity and stream function, the Euler equations are utilized in the Gromeka,Lamb form. The numerical algorithm is illustrated with several examples of steady flow through a two-dimensional channel with curved walls. The analysis of calculations shows strong dependence of the pressure field on the vorticity given at the inflow parts of the boundary. Plots of the flow structure and isobars, for different geometries of channel and for different values of vorticity on entrance, are also presented. Copyright © 2003 John Wiley & Sons, Ltd. [source]

A finite volume,multigrid method for flow simulation on stratified porous media on curvilinear co-ordinate systems

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 4 2001
Pablo Calvo
Abstract This paper presents a numerical study of infiltration processes on stratified porous media. The study is carried out to examine the performance of a finite volume method on problems with discontinuous solutions due to the transmission conditions in the interfaces. To discretize the problem, a curvilinear co-ordinate system is used. This permits matching the interface with the boundary of the control volumes that interchange fluxes between layers. The use of the multigrid algorithm for the resulting systems of equations allows problems involving a large number of nodes with low computational cost to be solved. Finally, some numerical experiments, which show the capillary barrier behaviour depending on the material used for the different layers and the geometric design of the interface, are presented. Copyright © 2001 John Wiley & Sons, Ltd. [source]