Saccharomyces cerevisiae (baker’s yeast) can exhibit sustained oscillations during the operation in a continuous bioreactor that adversely affects its stability and productivity. Because of heterogeneous nature of cell populations, the cell population balance equation (PBE) can be used to capture the dynamic behavior of such cultures. In this work, an unstructured-segregated model is used f...

In this article, we discuss the numerical solution of the Stokes and Navier-Stokes equations completed by nonlinear slip boundary conditions of friction type in two and three dimensions. To solve the Stokes system, we first reduce the related variational inequality into a saddle point-point problem for a well chosen augmented Lagrangian. To solve this saddle point problem we suggest an alternat...

In this paper, the finite element analysis of two-dimensional linear viscoelastic problems is performed using quadrilateral complex Fourier elements and, the results are compared with those obtained by quadrilateral classic Lagrange elements. Complex Fourier shape functions contain a shape parameter which is a constant unknown parameter adopted to enhance approximation’s accuracy. Since the iso...

This paper presents a new model of equivalent modulus derived from the Repeated Load CBR (RL-CBR) test without strain gauge. This model is an updated version of Araya et al. model (2011), the update consists of using the vertical strain as weighting factor instead of vertical displacement in the mean vertical and horizontal stresses calculation. The accuracy of equivalent modulus was improved b...

marine industry requires continued development of new technologies in order to produce oil. an essential requirement in design is to be able to compare experimental data from prototype structures with predicted information from a corresponding analytical finite element model. in this study, structural model updating may be defined as the fit of an existing analytical model in the light of measu...

A two-dimensional single particle finite element model was used to examine the effects of particle fragmental pattern on the average molecular weights, polymerization rate and particle overheating in heterogeneous Ziegler-Natta olefin polymerization. A two-site catalyst kinetic mechanism was employed together with a dynamic two-dimensional molecular species in diffusion-reaction equation. The i...

The Lagrange-Galerkin spectral element method for the two-dimensional shallow water equations is presented. The equations are written in conservation form and the domains are discretized using quadrilateral elements. Lagrangian methods integrate the governing equations along the characteristic curves, thus being well suited for resolving the nonlinearities introduced by the advection operator o...

in this paper, we use molecular dynamics and finite element simulations to determine the mechanical properties of single-crystal metal of silver (ag) with nano-holes. the lattice transition method from 3-dimensions into 2-dimentions in molecular dynamics simulation as well as plane stress model in finite element method, is used to lessen the simulation time consuming. elasticity module reductio...

The finite element procedure is developed for the solution of three-dimensional geometrically nonlinear problems with small strains and large rotational and translational displacements. Updated Lagrangian formulation is used with controlling strains and stresses at local coordinate frames at element integration points. Equilibrium iterations at each step are performed according to the Newton-Ra...

The aim of this thesis paper, to create a numerical model to examine the residual stresses induced by orthogonal machining in the finished work piece and the model is validated by comparing with experimental result. The finite element method is used to simulate and analyze the residual stresses induced by a orthogonal metal cutting process. A Dynamics explicit time integration technique with Ar...