S. M. Hosseini and E. Sonei,
Volume 22, Issue 1 (7-2003)
Abstract
In this paper, Forchheimer equation is used as the constitutive equation for flow through rockfill, and the non-linear two-dimensional governing equation with free surface is solved by a new finite element method in a fixed grid. The model is verified by applying it to different flow conditions. The first scenario, which is assumed to be one-dimensional with analytical solution available for it, is used to verify the developed code. Other scenarios, which are two-dimensional free surface tests on a laboratory rockfill, are used to verify the model. The model shows satisfactory performance in this regard. For example, on average, a mean absolute relative error of about 2.3%, in terms of pressure head was found to exist between modelling results and observed values. Further capabilities of the model are discussed by simulating overflow through self– spillway rockfill dams.
Keywords: Finite element, Method, Fixed grid, Non-Darcy flow, Non-linear flow, Rock fill dam
F. Daneshmand, M. Farid, and M.j. Kazemzadeh-Parsi,
Volume 27, Issue 2 (1-2009)
Abstract
In this paper, a modification on the fixed grid finite element method is presented and used in the solution of 2D linear elastic problems. This method uses non-boundary-fitted meshes for the numerical solution of partial differential equations. Special techniques are required to apply boundary conditions on the intersection of domain boundaries and non-boundary-fitted elements. Hence, a new method is also presented for the computation of stiffness matrix of boundary intersecting elements and boundary conditions of higher accuracy are applied. In order to examine the applicability of the proposed method, some
numerical examples are solved and the results are compared with those obtaioned from both fixed grid finite element and standard finite element methods.
