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See detailNumerical prediction of resulting rollover shapes and sheared edges after blanking process
Canales Cardenas, Cristian ULg; Boman, Romain ULg; Bussetta, Philippe et al

Conference (2015, April)

Over the years, the simulation of manufacturing processes has introduced several numerical challenges for researchers in computational mechanics. In particular, the numerical modeling of sheet metal ... [more ▼]

Over the years, the simulation of manufacturing processes has introduced several numerical challenges for researchers in computational mechanics. In particular, the numerical modeling of sheet metal blanking process involves different numerical issues that must be carefully treated: a large and highly localized deformation in the shearing zone prior to fracture, complex contact interactions between the tools and the metallic sheet and finally, the ductile failure phenomenon. Despite that this process is one of the most widely used cutting techniques for mass production, the process parameters are normally set by empirical evidence due to the physical complexity resulting from the extreme amount of shearing involved. In addition, the strain-rate dependent behavior of the material must be taken into account due to high punch velocities encountered in practice. Thus, an accurate numerical tool is extremely desirable to optimize the setting parameters of this technique and will lead to a better understanding of the process. [less ▲]

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See detailNumerical predictions of the performance in flight of an air-breathing hypersonic vehicle: HyShot II
Iaccarino, Gianluca; Pecnik, Rene; Terrapon, Vincent ULg et al

in Proceedings of the ASME 2010 International Mechanical Engineering Congress & Exposition; No IMECE2010-40186 (2010, November)

The uncertainties inherent to the operating conditions of the Hyshot II scramjet flight test are assessed. In particular, the variability of the pressure prediction in the combustor due to uncertain free ... [more ▼]

The uncertainties inherent to the operating conditions of the Hyshot II scramjet flight test are assessed. In particular, the variability of the pressure prediction in the combustor due to uncertain free stream conditions is investigated using a probabilistic methodology based on stochastic collocation. The uncertainties in Mach number, angle of attack and flight altitude are inferred from pressure measurements in the unfueled combustor using a Bayesian inversion approach. The forward computation relies on a reduced order model that represents the combustion processes in the scramjet combustor. A ground based experimental data set obtained from 1-to-1 model of the HyShot II vehicle with well defined operating conditions is used to validate the non-reacting solver and to calibrate the heat release model for the reacting combustor. The model prediction agrees well with the experimentally acquired flight data. On the other hand, our estimated flight free stream conditions differ from previously published results. [less ▲]

Detailed reference viewed: 28 (1 ULg)
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See detailNumerical Procedure for Calculation of Temperature Evolution in Composite Elements with Internal Cavities
Luycks, Pierre; Stienon, P.; Franssen, Jean-Marc ULg et al

in Communications in Numerical Methods in Engineering (1994), 10(6), 437-451

In the paper a computation code based on the finite-element method for temperature evolutions in composite elements with internal cavities is presented. It is suitable for the analysis of various thermal ... [more ▼]

In the paper a computation code based on the finite-element method for temperature evolutions in composite elements with internal cavities is presented. It is suitable for the analysis of various thermal problems encountered in mechanical and civil engineering such as fire risk assessment. It is based on a plane isoparametric triangular element with six nodes allowing the modelling of curved boundaries. In order to analyze composite steel-concrete elements and to take into account the non-linearities coming from the temperature-dependent material properties and from the boundary conditions, an implicit integration scheme is used. Another advantage of the program is the possibility of describing internal cavities with convection and radiation exchanges. In order to show the capacity of the program two examples are presented. Comparisons have been made with experimental and other numerical results, exhibiting very good agreement. [less ▲]

Detailed reference viewed: 25 (3 ULg)
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See detailNumerical processing of calculated echograms to derive stable room acoustics parameters
Embrechts, Jean-Jacques ULg

in Proceedings of the 104th Convention of the Audio Engineering Society, Convention paper nb. 4656 (1998)

Detailed reference viewed: 14 (4 ULg)
See detailNumerical Recipes - The Art of Scientific Computing -- W. H. Press et al.
Manfroid, Jean ULg

in Ciel et Terre (1987), 103

Not Available

Detailed reference viewed: 18 (3 ULg)
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See detailNumerical schemes for tracer studies in shallow shelf seas
Mercier, Christophe ULg

Doctoral thesis (2012)

Nowadays, tracers have revealed to be an invaluable integrated tool to investigate the different thematics related to coastal areas, shallow shelf seas or estuaries. In this work, they are used in ... [more ▼]

Nowadays, tracers have revealed to be an invaluable integrated tool to investigate the different thematics related to coastal areas, shallow shelf seas or estuaries. In this work, they are used in combination with a parallel scalable Fortran90 implementation of a 3D hydrodynamic model to study the transport of mud within the Belgian Coastal Zone. The results obtained illustrate the need for tools to understand the interactions between such highly energetic coastal areas and the sediment dynamics. The Constituent Age and Residence time Theory (CART), originally applied to passive tracers, is therefore extended to describe the sediments and used to quantify their rates of resuspension and horizontal transport. This application reveals some numerical issues that may degrade the reliability of the results. The different numerical parameterizations are thus revisited starting with the use of advection schemes, and especially, the Total Variation Diminishing (TVD) schemes built along the line defined by Harten. It is shown that the blind application of the usual TVD schemes and associated flux limiters can lead to non-TVD solutions when applied to complex geometries. Spatial and/or temporal variations of the bathymetry can indeed break the TVD property. Hopefully, really TVD schemes can be recovered by taking these variations into account in the formulation of the flux limiters. Even if its Eulerian formulation eases the implementation of CART into existing models, it is shown that CART's computation procedure lacks a numerical framework for a robust application. To address this, we enforce the consistency, defined as the requirement that the integration scheme does not introduce errors in the age field when aging is the only active process. Unfortunately, this does not guarantee the absence of overshootings. While it does not seem feasible to ensure a TVD behavior of the age field, appropriate modifications of the flux/slope limiters are derived here to prevent the occurrence of age values outside the physically acceptable range. On the bases of the solutions obtained after the advection of any numbers of tracers using high-order non-linear schemes, several control or global variables can be built. Even if the independent advection schemes used are specifically built to produce profiles free from the numerical artifacts that can spoil the physical meaning of the results, such global/control variables can exhibit these unwanted behaviors. This problematic is firstly treated with regard to the TVD schemes built from Harten's theorem. But guaranteeing the TVD property is not always feasible. Alternatively, appropriate modifications of the flux/slope limiters are implemented here to enforce a maximum principle for any global/control variable built as first-order homographic function of its components. [less ▲]

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See detailNumerical shear tests for different elasto-plastic laws
de Montleau, P.; Duchene, Laurent ULg; Flores, Paulo et al

in Onate, E.; Owen, D. R. J. (Eds.) Proceedings of the VII International Conference on Computational Plasticity (COMPLAS 2003) (2003)

This paper presents the numerical simulation of a cyclic simple shear test. The blank tested is a high strength steel sheet for which we use three different constitutive plastic laws derived from Teodosiu ... [more ▼]

This paper presents the numerical simulation of a cyclic simple shear test. The blank tested is a high strength steel sheet for which we use three different constitutive plastic laws derived from Teodosiu's model. These laws take into account respectively isotropic, kinematic and mixed isotropic-kinematic hardening. The goal of the paper is to provide a first numerical idea of the stress-strain path in the center of an experimental test sample. [less ▲]

Detailed reference viewed: 36 (7 ULg)
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See detailNumerical simulation and experimental validation of murine fracture healing
Geris, Liesbet ULg; Gerisch, A.; Maes, C. et al

in Proceedings of the fifth national day on biomedical engineering (2005)

Detailed reference viewed: 5 (0 ULg)
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See detailNumerical simulation and experimental validation of murine fracture healing
Geris, Liesbet ULg; Gerisch, A.; Maes, C. et al

in Proceedings of the European Conference on Mathematical and Theoretical Biology (2005)

Detailed reference viewed: 4 (0 ULg)
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See detailNumerical simulation and performance assessment of an absorption solar air-conditioning system coupled with an office building
Thomas, Sébastien ULg; Andre, Philippe ULg

in Building Simulation: An International Journal (2012), 5(3), 243-255

To minimize environmental impact and CO2 production associated with air-conditioning, it is reasonable to evaluate the prospects of a clean energy source. Solar energy, via thermal collectors can provide ... [more ▼]

To minimize environmental impact and CO2 production associated with air-conditioning, it is reasonable to evaluate the prospects of a clean energy source. Solar energy, via thermal collectors can provide a part of the heating needs. Moreover, it can drive absorption chiller in order to satisfy the cooling needs of buildings. The objective of the work is to evaluate accurately the energy consumption of an air-conditioning system including a solar driven absorption chiller. The complete simulation environment includes the absorption chiller itself, the cooling tower, the solar collectors field, heater, storage devices, pumps, heating-cooling distribution, emission system and building. A decrease of primary energy consumption of 22% for heating and cooling is reached when using a solar air-conditioning system instead of classical heating and cooling devices. The modelling of each subsystem is detailed. TRNSYS software modular approach provides the possibility to model and simulate this complete system. [less ▲]

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See detailNumerical simulation and performance assessment of an absorption solar air-conditioning system coupled with an office building
Thomas, Sébastien ULg; Andre, Philippe ULg

Conference (2010, December)

To minimize environmental impact and CO2 production associated with air-conditioning, it is reasonable to evaluate the prospects of a clean energy source. Solar energy, via thermal collectors can provide ... [more ▼]

To minimize environmental impact and CO2 production associated with air-conditioning, it is reasonable to evaluate the prospects of a clean energy source. Solar energy, via thermal collectors can provide a part of the heating needs. Moreover, it can drive absorption chiller in order to satisfy the cooling needs of buildings. The objective of the work is to evaluate accurately the energy consumption of an air conditioning system including a solar driven absorption chiller. The complete simulation environment includes the absorption chiller itself, the cooling tower, the solar collectors field, heater, storage devices, pumps, heating-cooling distribution, emission system and building. The modelling of each subsystem is detailed. TRNSYS software modular approach provides the possibility to model and simulate this complete system. [less ▲]

Detailed reference viewed: 72 (10 ULg)
Peer Reviewed
See detailThe numerical simulation and physical model test of pipeline under water action
Marchal, Jean ULg; Yucheng, Li; Guozhang, Lai et al

in Proceedings of the Fourth Pacific/Asia Offshore Mechanics Symposium, Pusan, Korea (1996)

Detailed reference viewed: 33 (0 ULg)
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See detailNumerical simulation and Visualization of Material Flow in Friction Stir Welding via Particle Tracing
Dialami, Narges; Chiumenti, Michele; Cervera, Miguel et al

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

This work deals with the numerical simulation and material flow visualization of Friction Stir Welding (FSW) processes. The fourth order Runge- Kutta (RK4) integration method is used for the computation ... [more ▼]

This work deals with the numerical simulation and material flow visualization of Friction Stir Welding (FSW) processes. The fourth order Runge- Kutta (RK4) integration method is used for the computation of particle trajectories. The particle tracing method is used to study the effect of input process parameters and pin shapes on the weld quality. The results show that the proposed method is suitable for the optimization of the FSW process. [less ▲]

Detailed reference viewed: 32 (6 ULg)
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See detailNumerical simulation in cold rolling using adiabatic strip model : application to large roll deformation
STEPHANY, A.; Ponthot, Jean-Philippe ULg; LEGRAND, N.

in AUSTRIB 06 (2006)

Detailed reference viewed: 24 (3 ULg)
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See detailNumerical Simulation of 1D Mixed Flow with Air/Water Interaction
Kerger, François ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in Transaction: Engineering Sciences, volume 1, Computational Methods in Multiphase Flow V (2009, June)

Detailed reference viewed: 59 (19 ULg)
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See detailNumerical Simulation of a Conical Shape Made By Single Point Incremental
Velosa De Sena, José ULg; Guzmán Inostroza, Carlos Felipe ULg; Duchene, Laurent ULg et al

in Incremental sheet forming (2014, January 06)

Detailed reference viewed: 50 (22 ULg)
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See detailNumerical Simulation of a Conical Shape Made by Single Point Incremental Forming
Velosa De Sena, José ULg; Duchene, Laurent ULg; Habraken, Anne ULg et al

in Incremental sheet forming (2014, May 08)

Detailed reference viewed: 38 (18 ULg)
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See detailNumerical simulation of a dam-break flood wave propagation in Belgium
Pirotton, Michel ULg; Lejeune, André ULg

in Berga, L. (Ed.) New trends and Guidelines on Dam Safety (1998)

Detailed reference viewed: 17 (3 ULg)