the complete 3d nonlinear dynamic problem of extensible, flexible risers conveying fluid is considered. for describing the dynamics of the system, the newtonian derivation procedure is followed. the velocity field inside the pipe formulated using hydrostatic and bernoulli equations. the hydrodynamic effects of external fluids are taken into consideration through the nonlinear drag forces in var...

a non-linear finite element model could be a useful tool in the development of a method of predicting soil pressure-sinkage behaviour, and can be used to investigate and analyze soil compaction. this study was undertaken to emphasize that the finite element method (fem) is a proper technique to model soil pressure-sinkage behaviour. for this purpose, the finite element method was used to model ...

The cracked Brazilian disc (CBD) specimen is widely used in order to determine mode-I/II and mixed-mode fracture toughness of a rock medium. In this study, the stress intensity factor (SIF) on the crack-tip in this specimen is calculated for various geometrical crack conditions using the extended-finite element method (X-FEM). This method is based upon the finite element method (FEM). In this m...

nowadays, one of the main problems encountered in minimally invasive surgery and telesurgery is the detection of arteries in tissue. in this study, for the first time, tactile detection of an artery in tissue and distinguishing it from the tumor has been modeled by finite element method. in this modeling, three 2d models of tissue have been created: tissue, tissue including a tumor, and tissue ...

In this paper, we use an extended form of the finite element method to study failure in polycrystalline microstructures. Quasi-static crack propagation is conducted using the extended finite element method (X-FEM) and microstructures are simulated using a kinetic Monte Carlo Potts algorithm. In the X-FEM, the framework of partition of unity is used to enrich the classical finite element approxi...

In Part I [Int. J. Solids Struct., 2003], we described the implementation of the extended finite element method (XFEM) within Dynaflowe, a standard finite element package. In our implementation, we focused on two-dimensional crack modeling in linear elasticity. For crack modeling in the X-FEM, a discontinuous function and the near-tip asymptotic functions are added to the finite element approxi...

1. Abstract This paper introduces h-Adaptive eXtended Finite Element Method (X-FEM) which is used for level set based structural optimization. Compared to X-FEM with uniform meshes, meshes of h-adaptive X-FEM are adequately adjusted so that meshes of higher resolution at the vicinity of the structural boundaries while meshes of relatively lower resolution in the regions far away from boundaries...

In this paper, we introduce an implementation of the extended finite element method for fracture problems within the finite element software ABAQUSTM. User subroutine (UEL) in Abaqus is used to enable the incorporation of extended finite element capabilities. We provide details on the data input format together with the proposed user element subroutine, which constitutes the core of the finite ...

This study presents a fast and exact computational method for crack propagation which is based on the extended finite element method (X-FEM). It is well known that the X-FEM has been developed to be an important numerical method for crack propagation. However, there are still some limitations on the computational cost due to the requirements of very refined meshes and very small iteration step ...

A new nite element method for elliptic problems with locally periodic microstructure of length " > 0 is developed and analyzed. It is shown that the method converges, as " ! 0, to the solution of the homogenized problem with optimal order in " and exponentially in the number of degrees of freedom independent of " > 0. The computational work of the method is bounded independently of ". Numerical...