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Peer Reviewed
See detailExperimental study of the drying kinetic of mortar
Kahlerras, Loubna ULg; Michel, Frédéric ULg; Courard, Luc ULg et al

Poster (2014, August 24)

This work reports the results of an experimental study concerning on one hand the influence of water-to cement ratios (W/C), and the role of aggregates on the other hand on the drying kinetics of cement ... [more ▼]

This work reports the results of an experimental study concerning on one hand the influence of water-to cement ratios (W/C), and the role of aggregates on the other hand on the drying kinetics of cement pastes during thermal drying. Three types of cement pastes were realized and studied; cement pastes with ratios W/C 0.4, W/C 0.5 and mortar with ratio W/C 0.5. These tries present the advantage to reproduce the natural conditions met in the problems of interaction atmosphere and material. Cylindrical samples of cement of size (17 X 13) mm are dried in a convective dryer. The sample is continuously weighed during the drying test and its mass is recorded every 60 s, in the purpose to obtain the drying curves. The results show that the increase of the W/C ratio leads to an increase of the drying rate due to the increase of the initial porosity. The effect of the introduction of aggregates is observable by the comparison of the drying curve obtained for the mortar and the cement pastes. The results show a decrease of the drying kinetics with mortars. The results also show that the air drying temperature has a large impact on the drying process, increasing the temperature leading to significant drying time reduction. The Effective diffusion coefficient is calculated by comparison between the experimental results and the analytical solution of Fick’s equation written for a finite medium. [less ▲]

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See detailExperimental Study of the Human Ability to Deliberately Excite a Flexible Floor
Schwartz, Cédric ULg; Berger, Alexis; Bruls, Olivier ULg et al

in Zingoni, Alphose (Ed.) Proceedings of the 5th International Conference on Structural Engineering, Mechanics and Computation (2014)

Human-structure interactions are not completely understood yet. This paper presents an experimental study focusing on the interaction between a human and a flexible support, with a major aim to better ... [more ▼]

Human-structure interactions are not completely understood yet. This paper presents an experimental study focusing on the interaction between a human and a flexible support, with a major aim to better understand how the behavior of a human subject, bouncing on a flexible structure, adapts to the support motion. Exploratory experiments are undertaken with a 7m-span timber footbridge tested in the Human Motion Analysis Laboratory of the University of Liege. The movements of the coupled system composed of the subject and the footbridge are recorded by Motion Capture technology; the subject\textquoteright{}s 3-D body motion is defined by three important angles: ankle, knee and hip. The interaction between the subject and the footbridge is also quantified by means of force platform measurements. The experiments indicate an influence of the support amplitude and natural frequency on the phase shift between the oscillatory floor motion and the three angles characterizing the motion. [less ▲]

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See detailExperimental study of the hydraulic behavior of piano key weirs
Machiels, Olivier ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in Proc. 17th Congress of the Asia and Pacific Division of the International Association of Hydro-Environment Engineering and Research (2010)

Detailed reference viewed: 147 (4 ULg)
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See detailExperimental study of the hydraulic behaviour of Piano Key Weirs
Machiels, Olivier ULg

Doctoral thesis (2012)

Detailed reference viewed: 177 (34 ULg)
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See detailExperimental Study of the Integration of a Scroll Expander into a Heat Recovery Rankine Cycle
Lemort, Vincent ULg; Teodorese, Ion

(2006, July)

This study investigates the possibility to associate a scroll expander to a heat recovery Rankine cycle, working with water. In view to develop such a scroll expander, three scroll compressors are adapted ... [more ▼]

This study investigates the possibility to associate a scroll expander to a heat recovery Rankine cycle, working with water. In view to develop such a scroll expander, three scroll compressors are adapted to be run in expander mode. The three tested expanders are fed with water steam and air. Two of them need to be lubricated. The third expander is also fed with a binary mixture of water and propylene glycol. A model of scroll expander is proposed and validated. [less ▲]

Detailed reference viewed: 122 (7 ULg)
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See detailExperimental study of the interaction between a turbulent flow and a river biofilm growing on macrorugosities
Moulin, F. Y.; Peltier, Yann ULg; Bercovitz, Y. et al

in International Conference in Hydroscience and Engineering 2008 (2008)

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See detailExperimental study of the magnetic shielding performances of a Bi2223 tube closed by a Bi2223 cap.
Wera, Laurent ULg; Fagnard, Jean-François ULg; Hogan, Kevin ULg et al

Poster (2014, August 12)

A superconducting tube can be used as an efficient magnetic shield. However, the shielding factor (defined as the ratio between the applied magnetic induction and the magnetic induction measured inside ... [more ▼]

A superconducting tube can be used as an efficient magnetic shield. However, the shielding factor (defined as the ratio between the applied magnetic induction and the magnetic induction measured inside the tube) decreases towards tube extremities because of the field penetration through the open ends of the tube. To improve the performances at tube extremities, the tube should be closed. This can be achieved by using a superconducting vessel or by closing both extremities with a cap. The purpose of the present work is to study experimentally the shielding performances of a Bi2223 tube closed by a superconducting Bi2223 cap. The cap is a circular plate with a diameter equal to the outer diameter of the tube and there is no superconducting joint between the cap and the tube. Our interest is to characterize the effect of the cap on the shielding factor distribution along the tube axis when only one extremity of the tube is closed. We also study the effect of the gap size between the cap and the tube in axial configuration. Finally, a tube closed at its both ends is also characterized. All experiments are carried out at 77K. The tube is subjected to a quasi-static (“DC”) uniform magnetic field. A Hall probe measures the three components of the local magnetic induction along the axis of the tube as a function of the applied magnetic induction. Results show that the shielding performances in the axial configuration are highly improved at the closed extremity as the cap reduces the penetration through the open end. The shielding factor distribution along the tube axis is affected by the presence of the cap. For an open tube, the shielding factor is maximum near the center and decreases towards both extremities. For the tube closed at one extremity, the shielding factor is maximum at the closed extremity and decreases towards the center. Moreover, the shielding factor distribution between the tube center and the open extremity is not affected by the presence of the cap. The experimental results show that, a small gap between the tube and the cap, which can be necessary for applications, does not strongly affect the magnetic shielding performances of the assembly. [less ▲]

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See detailExperimental study of the non-linear behaviour of beam-to-column bolted joints.
Janss, J.; Jaspart, Jean-Pierre ULg; Maquoi, René ULg

in Proceedings of a State-of-the art workshop on connections and the behaviour, strength and design of steel structures. (1988, February)

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See detailExperimental study of the non-linear behaviour of beam-to-column composite joints
Altmann, R.; Maquoi, René ULg; Jaspart, Jean-Pierre ULg

in Journal of Constructional Steel Research (1991), 18

Detailed reference viewed: 28 (1 ULg)
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See detailExperimental study of the non-linear behaviour of beam-to-column composite joints.
Altmann, R.; Maquoi, René ULg; Jaspart, Jean-Pierre ULg

in proceeding du Workshop COST C1 (1992)

Detailed reference viewed: 19 (2 ULg)
Peer Reviewed
See detailExperimental study of the non-linear behaviour of beam-to-column composite joints.
Altmann, R.; Maquoi, René ULg; Jaspart, Jean-Pierre ULg

in Proceedings of the International colloquium on stability of steel structures (1990)

Detailed reference viewed: 16 (1 ULg)
See detailExperimental study of the thermo-hydraulic performances of air-cooled radiators
Ngendakumana, Philippe ULg; Trebilcock, Felipe

Report (2004)

Detailed reference viewed: 6 (0 ULg)
See detailExperimental study of the thermo-hydraulic performances of humid air condensers
Cuevas, Cristian; Trebilcock, Felipe; Ngendakumana, Philippe ULg

Report (2003)

Detailed reference viewed: 10 (0 ULg)
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See detailAn experimental study of the use of acoustic diffusers to reduce noise in urban areas
Picaut, Judicaël; Hossam Eldien, Hany; Billon, Alexis ULg

Conference (2010, June)

The use of acoustic diffusers to reduce noise in urban areas has been recently numerically investigated [Acta Acustica united with Acustica, Vol. 95 (2009), p. 653–668]. It was shown that a significant ... [more ▼]

The use of acoustic diffusers to reduce noise in urban areas has been recently numerically investigated [Acta Acustica united with Acustica, Vol. 95 (2009), p. 653–668]. It was shown that a significant noise reduction can be observed by considering diffusers on the building façades. In the present study, an experimental investigation is proposed to validate last results. Measurements are carried out using a 1:10 urban street scale model, with and without acoustics diffusers, in order to evaluate the “real” effect of such devices, for several configurations. Results, in terms of sound attenuation and reverberation, show that a positive effect can be observed, provided that diffusers are well designed for the reduction of road traffic noise. [less ▲]

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See detailExperimental study of velocity fields in rectangular shallow reservoirs
Dewals, Benjamin ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in Journal of Hydraulic Research (2012), 50(4), 435-436

The Authors of the discussed paper present the results of an experimental study to improve the flow classification in rectangular shallow reservoirs. Although previous papers have paved the way for this ... [more ▼]

The Authors of the discussed paper present the results of an experimental study to improve the flow classification in rectangular shallow reservoirs. Although previous papers have paved the way for this classification (Dewals et al. 2008, Dufresne et al. 2010), the Authors are complemented for the detailed flow field measurements conducted for a high number of reservoir geometries. For the tested hydraulic conditions, the Authors report a transition zone corresponding to an ‘unstable’ flow pattern. Repeated tests under similar conditions lead alternately to a symmetric or an asymmetric flow field. In this discussion, it is intended below to shed light on this transition zone using 2D numerical simulations. The Authors state that the flow in the transition zone is sensitive to so-called ‘external perturbations’, whereas we argue that the flow is particularly influenced by the initial test conditions. Using a particular post-processing of the computed flow fields, a hysteresis effect is detected. [less ▲]

Detailed reference viewed: 91 (23 ULg)
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See detailExperimental study of wings undergoing active root flapping and pitching
Abdul Razak, Norizham; Dimitriadis, Grigorios ULg

in Journal of Fluids & Structures (2014), 49

This paper presents the results of experiments carried out on mechanical wings undergoing active root flapping and pitching in the wind tunnel. The objective of the work is to investigate the effect of ... [more ▼]

This paper presents the results of experiments carried out on mechanical wings undergoing active root flapping and pitching in the wind tunnel. The objective of the work is to investigate the effect of the pitch angle oscillations and wing profile on the aerodynamic forces generated by the wings. The experiments were repeated for different reduced frequency, airspeed, flapping and pitching kinematics, geometric angle of attack and wing sections (one symmetric and two cambered airfoils). A specially designed mechanical flapper was used, modelled on large migrating birds. It is shown that, under pitch leading conditions, good thrust generation can be obtained at a wide range of Strouhal numbers if the pitch angle oscillation is adjusted accordingly. Consequently, high thrust was measured at both the lowest and the highest tested Strouhal numbers. Furthermore, the work demonstrates that the aerodynamic forces can be sensitive to the Reynolds number, depending on the camber of the wings. Under pitch lagging conditions, where the effective angle of attack amplitude is highest, the symmetric wing was affected by the Reynolds number, generating less thrust at the lowest tested Reynolds value. In contrast, under pure flapping conditions, where the effective angle of attack amplitude was lower but still significant, it was the cambered wings that demonstrated Reynolds sensitivity. [less ▲]

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See detailExperimental study on an open-drive scroll expander integrated into an ORC (Organic Rankine Cycle) system with R245fa as working fluid
Declaye, Sébastien ULg; Quoilin, Sylvain ULg; Guillaume, Ludovic ULg et al

in Energy (2013), 15

The present paper focuses on the experimental characterization of an open-drive scroll expander integrated into an Organic Rankine cycle using R245fa as working fluid. The expander is a commercially ... [more ▼]

The present paper focuses on the experimental characterization of an open-drive scroll expander integrated into an Organic Rankine cycle using R245fa as working fluid. The expander is a commercially available air compressor that was modified to operate in expander mode. The ORC (Organic Rankine Cycle) system is designed for a nominal heat input of 20 kW and a nominal net power output of 1.8 kW. A total of 74 steady-state operating points are measured to evaluate the expander performance over a wide range of conditions. The operating parameters that are varied include the inlet pressure (from 9 to 12 bar), outlet pressure (from 1.5 to 4 bar) and rotational speed (from 2000 to 3500 rpm). The maximum isentropic efficiency and shaft power are, respectively, 75.7% and 2.1 kW. A maximum cycle efficiency of 8.5% is reached for evaporating and condensing temperatures of 97.5 °C and 26.6 °C respectively. For most of the tests, hot water is produced in the condenser and the system therefore behaves as a CHP (combined heat and power). Depending on the water temperature requirement, a power to heat ratio varying between 1.9% and 11.8% is obtained. Water over 50 °C can be produced with a power to heat ratio higher than 8%. The experimental data points are then used to generate a performance map of the expander. This performance map allows for simulation of the use of such an expander in other ORC system [less ▲]

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See detailExperimental study on dehumidification/regeneration of liquid desiccant: LiBr solution
Bouzenada, Saliha; Kaabi, Abdennacer N; Fraikin, Laurent ULg et al

in Procedia Computer Science (2014), 32

The growing demand for air conditioning has caused a significant increase in demand for energy resources. The traditional commercial, non natural working fluids, like CFC, HCFC and HFC result in both ... [more ▼]

The growing demand for air conditioning has caused a significant increase in demand for energy resources. The traditional commercial, non natural working fluids, like CFC, HCFC and HFC result in both ozone depletion and global warming emission of CO2. The use of hygroscopic salts in direct contact with moist air provides an attractive alternative to conventional cooling systems. The liquid desiccant can substitute the dangerous fluids. The main operations in Liquid Desiccant Cooling System (LDCS) are dehumidification and regeneration. This paper presents an experimental study of dehumidification/regeneration processes using LiBr as liquid desiccant in direct contact with the air at different operating conditions. An analysis of the mass transfer is made in order to prove is this material is the best liquid desiccant for LDCS. Experimental results showed the effect of air conditions on mass transfer. It can be seen that LiBr is able to absorb moisture and can be regenerated at low temperature. © 2014 Published by Elsevier B.V. [less ▲]

Detailed reference viewed: 79 (7 ULg)