Articles techniques et présentations

Using COMSOL Multiphysics, a finite element model is introduced in this paper to describe the couplings between the welding arc and the weld pool dynamic in pulsed gas tungsten arc welding. The cathode, arc-plasma and melting anode regions are taken into account. The unified time ... En savoir plus

A 1D phase change problem, known as Stefan’s problem, for which analytical solutions are available, is solved as a 2D problem using COMSOL Multiphysics. The PCM medium is semi-infinite, initially solid at its melting temperature Tm, and at t = 0, the wall temperature is raised to Tw > ... En savoir plus

Variable capacitors between the fF and pF range are very interesting for high frequency applications like variable filters, resonators, etc. For radio astronomy applications variable capacitors, realized by electrostatically actuated, micromechanical Meanders-suspended bridges (MEMS) ... En savoir plus

Part of a 120mm gun has been represented as a perforated conic iron solid, surrounded by an annular screen. Inside the gun are limit conditions of isolation or thermal flux. The screen is described as a shell, receiving solar heat and exchanging with the outside atmosphere. It bears a ... En savoir plus

Drug therapy of the posterior part of an eye is very challenging. Yet, in USA alone, there are almost 2 million people affected by age related macular degeneration. When designing a strategy for controlled-release drug delivery, it is important to take into account of physiology, ... En savoir plus

Second-generation high-temperature superconducting (HTS) tapes are very promising superconductors for ac applications and numerical models are very important for predicting their performance, e.g. for computing the ac losses. These tapes are characterized by a very large aspect ratio: ... En savoir plus

In recent years, a number of numerical and finite-element-methods in particular - some implemented in COMSOL - have been developed to investigate various properties of superconducting materials. Following converse conclusions by different models regarding similar physical phenomena, the ... En savoir plus

Given any equation L(u)=0, e.g. a partial differential equation, it can be considered to be the stationary solution of a time dependent equation (in fact, time need only to be fictitious time not real time). Our approach is to choose the time dependence in analogy with an oscillating ... En savoir plus

Fluids used in biomedical microelectromechanical systems (BioMEMS) devices often exhibit very different flow behavior from those in bulk solutions, which in turn affects the behavior of cells and biomolecules in the device. In this work, we investigate an integrated microfluidic system ... En savoir plus

A packed bed reactor consisting of spherical catalyst particles in a tube was simulated numerically. The steady-state pseudo-heterogeneous model consisted of a pseudo-continuum representation for the heat and mass transfer in the reactor tube. The reaction source terms were evaluated by ... En savoir plus