Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailNumerical Simulation of Cold Roll Forming Process
Bui, Quoc Viet; Papeleux, Luc ULg; Boman, Romain ULg et al

in Banabic, Dorel (Ed.) Proceedings of the 8th ESAFORM Conference on Material Forming (2005, April)

Cold roll-forming process of a U profile is modelled and simulated. The simulation is based on a 3D finite element analysis with the help of the home made Metafor code. The prediction on dimensions and ... [more ▼]

Cold roll-forming process of a U profile is modelled and simulated. The simulation is based on a 3D finite element analysis with the help of the home made Metafor code. The prediction on dimensions and deformed shape of the cold roll-formed sheet is in good agreement with the experimental results. Parametric study on roll forming parameters, such as the yield limit and the hardening property of materials, and the distance between stations is performed. [less ▲]

Detailed reference viewed: 59 (15 ULg)
Full Text
Peer Reviewed
See detailNumerical simulation of cold roll-forming processes
Bui, Quoc viet; Ponthot, Jean-Philippe ULg

in Journal of Materials Processing Technology (2008), 202(1-3), 275-282

3D finite element analysis is employed to simulate a cold roll-forming process. Numerical results of longitudinal strains and displacement trajectories are compared with experimental results available in ... [more ▼]

3D finite element analysis is employed to simulate a cold roll-forming process. Numerical results of longitudinal strains and displacement trajectories are compared with experimental results available in the literature. Through a parametri study, significant impacts of the yield limit and the work-hardening exponent on the product quality are observed, whereas forming speed and friction at roll-sheet interface appear to play a minor role. (C) 2007 Elsevier B.V. All rights reserved. [less ▲]

Detailed reference viewed: 77 (5 ULg)
Full Text
Peer Reviewed
See detailNumerical simulation of compacting process of a multi-stepped part – Comparison with experiments
Mosbah, P.; Shima, S.; Habraken, Anne ULg et al

in Journal of the Japan Society of Powder and Powder Metallurgy (1999), 46

Detailed reference viewed: 16 (3 ULg)
Peer Reviewed
See detailNumerical simulation of crashworthiness with an implicit finite element code
Graillet, Denis; Ponthot, Jean-Philippe ULg

in Aircraft Engineering & Aerospace Technology (1999), 71(1), 12-20

Implicit and explicit time integration schemes in conjunction with the finite element method are presented for the transient response of highly non-linear problems such as impact situations exhibiting ... [more ▼]

Implicit and explicit time integration schemes in conjunction with the finite element method are presented for the transient response of highly non-linear problems such as impact situations exhibiting important material dissipation. Surprisingly the implicit schemes lead to excellent convergence properties that make them a cost-efficient alternative to explicit scheme generally advocated as the best choice for these problems. As numerical illustrations, we present here the academic impact between two flexible bodies, a long tube and a long plate, as well as a more industrial-oriented application: the impact between a fan blade and a double casing. [less ▲]

Detailed reference viewed: 49 (4 ULg)
Full Text
Peer Reviewed
See detailNumerical Simulation of Double Cup Extrusion Test Using the Arbitrary Lagrangian Eulerian Formalism
Boman, Romain ULg; Koeune, Roxane; Ponthot, Jean-Philippe ULg

in Idelsohn, Sergio R. (Ed.) Numerical Simulations of Coupled Problems in Engineering (2014)

In this chapter Double Cup Extrusion Test (DCET) is modelled using the finite element method with the help of the Arbitrary Lagrangian Eulerian (ALE) formalism. DCET is a tribological test involving very ... [more ▼]

In this chapter Double Cup Extrusion Test (DCET) is modelled using the finite element method with the help of the Arbitrary Lagrangian Eulerian (ALE) formalism. DCET is a tribological test involving very large deformations which are traditionally dealt with complicated and costly remeshing algorithms. Since the topology of ALE meshes should remain constant throughout the simulation, twovery thin layers of auxiliary elements are added to the initial mesh of the billet where the material is expected to flow. This numerical trick is combined with an original and efficient node relocation procedure which allows the model to take into account complex geometries of punches. The presented model is firstly validated for limited punch strokes thanks to a purely Lagrangian simulation. It is then compared with results from the literature. Eventually the general nature and the effectiveness of this numerical strategy is demonstrated by a fully-coupled thermomechanical simulation of thixoforming where the final shape of the billet is compared to experimental measurements. [less ▲]

Detailed reference viewed: 6 (1 ULg)
Full Text
Peer Reviewed
See detailNumerical Simulation of Double Cup Extrusion Test using the Arbitrary Lagrangian Eulerian Formalism
Boman, Romain ULg; Koeune, Roxane; Ponthot, Jean-Philippe ULg

in Proceedings of Coupled Problems 2013 (2013, June)

Detailed reference viewed: 46 (16 ULg)
Full Text
Peer Reviewed
See detailNumerical simulation of DP steel damage using a physically-based GTN model
Fansi, Joseph; Habraken, Anne ULg; Balan, Tudor et al

Poster (2012)

Poster describing the identification and use of Gurson model on DP Steel

Detailed reference viewed: 31 (17 ULg)
Full Text
Peer Reviewed
See detailNumerical simulation of drying under variable external conditions: application to solar drying of seedless grapes
Bennamoun, Lyes ULg; Belhamri, Azeddine

in Journal of Food Engineering (2006), 76(2), 179-187

Detailed reference viewed: 8 (2 ULg)
Full Text
Peer Reviewed
See detailNumerical simulation of elastoviscoplastic large strains of metals at high temperature.
Cescotto, Serge ULg; Charlier, Robert ULg

in Proc. 8th Conf. on SMIRT (1985, August)

Detailed reference viewed: 8 (0 ULg)
Full Text
Peer Reviewed
See detailNumerical simulation of finite strain viscoplastic problems
Garcia-Garino, Carlos; Andia fages, Susana; Mirasso, Anibal et al

in International Journal of Computational & Applied Mathematics (2013), 246

A large strain elastoplastic constitutive model based on hyperelasticity and multiplicative decomposition of deformation gradient tensor is extended to viscous case, in a framework similar to the one that ... [more ▼]

A large strain elastoplastic constitutive model based on hyperelasticity and multiplicative decomposition of deformation gradient tensor is extended to viscous case, in a framework similar to the one that has been proposed by Ponthot in an hypoelastic context. In this way a very useful framework can be obtained, able to deal with both rate dependent and rate independent problems. In this work a review of theoretical details and numerical implementation of the model are discussed. Similarly to what is done in rate independent plasticity, a Newton–Raphson scheme has been used to solve the non linear consistency condition in order to compute the viscoplastic multiplier. A plane strain plate with a central circular hole under tension is simulated in order to test the proposed model. Large deformation effects are considered in all the simulations carried out. Different parameters of the constitutive model are varied in order to study the sensitivity of the proposed algorithm. [less ▲]

Detailed reference viewed: 12 (1 ULg)
Full Text
Peer Reviewed
See detailNumerical simulation of heat transfer associated with low enthalpy geothermal pumping in an alluvial aquifer
Fossoul, Frédérique ULg; Orban, Philippe ULg; Dassargues, Alain ULg

in Geologica Belgica (2011), 14(1-2),

In a context favourable to renewable energies, various aquifers are studied to supply heating and/or cooling systems. The groundwater flow and heat transport are modelled in the alluvial aquifer of the ... [more ▼]

In a context favourable to renewable energies, various aquifers are studied to supply heating and/or cooling systems. The groundwater flow and heat transport are modelled in the alluvial aquifer of the river Meuse in providing an integrated tool for assessing the feasibility of a low energy air cooling/heating system for a large office building by pumping groundwater and discharging it in the river after being heated/cooled by using heat pumps. First, a comparative sensitivity analysis is performed using different codes for assessing the influence of coupling and non linearities on the main parameters due to the temperature evolution in function of time. Then, assuming that the aquifer temperature variation is weak enough to neglect its influence on hydrodynamics and thermal parameters, the MT3DMS and HydroGeoSphere codes are used for modelling the actual case-study. In practice, the worst case scenario considered by the project manager is the cooling of the office building during the hottest summer conditions. So, the influence of the warm water from the river Meuse is computed as it constitutes the major limiting factor. An optimisation of the pumping schema is computed to maximise the efficiency of the system. [less ▲]

Detailed reference viewed: 140 (26 ULg)
Full Text
See detailNumerical simulation of heat transport associated with groundwater pumping in an alluvial aquifer
Fossoul, Frédérique ULg; Orban, Philippe ULg; Dassargues, Alain ULg

Conference (2009, September)

In a context more favourable to renewable energies, various aquifers are studied to feed heating and/or cooling systems. The groundwater flow and heat transport are modelled in the alluvial aquifer of the ... [more ▼]

In a context more favourable to renewable energies, various aquifers are studied to feed heating and/or cooling systems. The groundwater flow and heat transport are modelled in the alluvial aquifer of the river Meuse in order to provide an integrated tool for assessing the feasibility of a low energy air cooling /heating system for a large office building by pumping groundwater and discharging in the river. First, a comparative sensitivity analysis is performed using three different codes (MT3D, SHEMAT and HYDROGEOSHERE) for assessing the influence of coupling and non linearities in the main parameters due to the temperature evolution in function of time. Then, assuming that the variations of the aquifer temperature are weak enough to neglect their influence on hydrodynamics and thermal parameters, the MT3D and HYDROGEOSPHERE codes are used for modelling the actual case-study. In practice, for cooling the office building with groundwater initially at 13°C, the main influence of the relative hot water from the river Meuse (in hot summer conditions 27°C) is computed and constitutes the major limiting factor. An optimisation of the pumping schema is computed to maximise the efficiency of the cooling/heating system. [less ▲]

Detailed reference viewed: 86 (26 ULg)
Full Text
Peer Reviewed
See detailNumerical Simulation of High Drag Reduction Regime in Polymer Solutions
Dubief, Yves; White, Christopher M.; Terrapon, Vincent ULg et al

in Proceedings of the 4th ASME/JSME Joint Fluids Engineering Conference; No FEDSM2003-45652 (2003, July)

The simulation of drag reduced channel flows has to rely on consitituve models such as FENE-P. Their implementation is not straightforward to achieve convergence and stability of the solution. This paper ... [more ▼]

The simulation of drag reduced channel flows has to rely on consitituve models such as FENE-P. Their implementation is not straightforward to achieve convergence and stability of the solution. This paper discusses the problem of advection embedded in the FENE-P equation and the issue of the domain size. Finally we present results of simulations for High Drag Reduction regime, and show the subsequent modification of the vortical structures. [less ▲]

Detailed reference viewed: 21 (2 ULg)
Full Text
Peer Reviewed
See detailNumerical Simulation of Hot Isostatic Pressing of Metal Powder: Influence of Constitutive Equations
Argento, C.; Bouvard, D.; Stutz, P. et al

in Acte du Powder Metallurgy World Congress (1994, June)

Detailed reference viewed: 30 (0 ULg)
Full Text
Peer Reviewed
See detailNumerical simulation of impedance and admittance of OLEDs
Nguyen, Ngoc Duy ULg; Schmeits, Marcel

in Physica Status Solidi : A. Applications and Materials Science (2006), 203

The electrical characteristics of organic light-emitting devices are calculated for the dc and ac regimes by numerically solving the basic semiconductor equations under steady-state and small-signal ... [more ▼]

The electrical characteristics of organic light-emitting devices are calculated for the dc and ac regimes by numerically solving the basic semiconductor equations under steady-state and small-signal conditions. For a given structure, the dc and ac electric potential and electric field, the electron and hole concentrations, as well as the different components of the current density are obtained as function of the one-dimensional spatial coordinate. This approach allows a detailed microscopic description of the dependencies of these quantities on the applied steady-state voltage V0 and the frequency of the modulating voltage. The final output consists in the frequency-dependent complex admittance and impedance of the device, the real and imaginary parts of which are the experimentally-available data. As a typical example, we show the results for a two-layer structure where α-NPD is the hole-transporting material and Alq3 the electron-transporting material. The anode is made of ITO and Al/LiF composes the cathode. The admittance and impedance curves, yielded by the numerical simulation as functions of the modulation frequency, are fitted by an equivalent electrical circuit, the elements of which are resistances and capacitances. The number of com- ponents depends on the structure composition and on the applied steady-state voltage. We show that each element can be associated with a particular region of the device. This allows to correlate the dependence of each feature of the admittance and impedance curves with one or several parameters describing the ma- terial system. Such an analysis can be useful for the inverse approach, where, starting from measurements of the electrical ac characteristics, the aim is to get information on the microscopic mechanisms which contribute to the electrical conduction of the device. [less ▲]

Detailed reference viewed: 75 (6 ULg)
See detailNumerical simulation of large strain rate dependent J2 problems
GARCIA GARINO, A.; Ponthot, Jean-Philippe ULg; MIRASSO, A. et al

in Proceedings of ENIEF 2006, Mecanica Computational (2006, November)

Detailed reference viewed: 21 (3 ULg)
Full Text
Peer Reviewed
See detailNumerical Simulation of Lubricated Contact between Solids in Metal Forming Processes using the Arbitrary Lagrangian Eulerian Formulation
Boman, Romain ULg; Ponthot, Jean-Philippe ULg

in Simulation of Material Processing: Theory, Methods and Application: Proceedings of the 7th International Conference NUMIFORM 2001 (2001, June)

Detailed reference viewed: 19 (10 ULg)
Full Text
Peer Reviewed
See detailNumerical Simulation of Lubricated Contact in Rolling Processes
Boman, Romain ULg; Ponthot, Jean-Philippe ULg

in Journal of Materials Processing Technology (2002), 125-126

In this paper, the lubrication problem in numerical simulation of rolling process is presented. In this case, the recent and complex model of Marsault for the solution of the mixed lubrication regime has ... [more ▼]

In this paper, the lubrication problem in numerical simulation of rolling process is presented. In this case, the recent and complex model of Marsault for the solution of the mixed lubrication regime has been implemented and tested. This model requires the use of the finite difference method to work properly. We will discuss the advantages and the difficulties encountered when trying to solve the same problem with the finite element method in a general frame. Finally, a finite element formulation for the solution of the time-dependent Reynolds' equation coupled with the deformation of the workpiece is proposed. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

Detailed reference viewed: 107 (10 ULg)
See detailNumerical simulation of materials submitted to high strain rates. A thermomechanical coupled approach
Jeunechamps, Pierre-Paul ULg; Ponthot, Jean-Philippe ULg

in Int. Conf. on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2007 (2007)

Detailed reference viewed: 11 (1 ULg)