Articles techniques et présentations

COMSOL\'s new CFD Module has been tested for laminar and turbulent flows in simple geometries, with couple or segregated solver. These tests allow mesh sensitivities and comparison with analytical solutions. They also give a first idea of cpu time and RAM use for standard cases. In a ... En savoir plus

Geothermal heat production from deep reservoirs (5000-7000 m) is currently examined, not only in Germany. Our reference set-up consists of two pipes within a single borehole: one for pumping. We examine a design, where a single borehole splits into two legs at a certain depth. The two ... En savoir plus

The CWRU Turbine is a research turbine located in a urban campus in Cleveland, Ohio. This location may create turbulence, resulting in a possible loss in energy generation. This research attempts to answers the question of whether the wind flow is affected by the buildings or not. The ... En savoir plus

A hybrid technique based on the use of the FEM and the transfer matrix method is used to identify the frequencies at which thermoacoustic instabilities are expected and the growth rate of the pressure oscillations at the onset of instability. The Helmholtz equation is used to model the ... En savoir plus

In this paper a mathematical model for predicting the heating-up of an acetylene cylinder involved in a fire is presented. In the simulations polynomial functions were used to describe the temperature dependency of the thermal properties of the cylinder interior, which is a complex ... En savoir plus

Fuel vapor restraint systems are used in vehicles to avoid discharge of volatile hydrocarbons from fuel tanks. The topic of this paper is the proper operation of fuel vapor restraint systems depending on the composition of bioethanol-fuel-blends. Experimental data serve as input to a ... En savoir plus

Surface discharge initiation and propagation on the surface of an insulating solid immersed in a dielectric liquid were examined numerically and experimentally. To establish a generalized numerical technique for evaluating surface discharge phenomena using the electrohydrodynamics (EHD) ... En savoir plus

A compression driver is a certain type of electrodynamic loudspeaker which has a phase plug with slits in front of the diaphragm. The slits are narrow enough that the so-called viscothermal effects are of significant importance. In this paper a 2D axisymmetric finite element model of a ... En savoir plus

For a better understanding of phenomena associated to the appearance of defects in laser welding, a heat and fluid flow model is developed. This study is focused on the modeling of a static laser shot on a sample of steel. This 2D axialsymmetric configuration is used to study phenomena ... En savoir plus

In a soil pore, water flows through the biofilm, where the density of the latter was assumed to represent a flow resistance. This mechanism was implemented as a local change of fluid viscosity proportional to local biofilm density. It was assumed that diffusive substrate transport is ... En savoir plus