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The turbulent plunging jet of a nearly incompressible fluid into a stagnant fluid is of great importance in many practical applications, especially for the engineering of hydropower. As an example, the dynamic load exerted by the impact of turbulent high-velocity jets into a pool must be estimated to evaluate the potential destabilization of a rock bed or dam’s structure. Modelling plunging jets in the laboratory presents a challenge due to the complex two-phase environment, which requires models to be built at near-prototype scales. This paper deals with the application of a three-dimensional weakly compressible smoothed particle hydrodynamics (SPH) model to study a circular jet impinging into a water flat pool, at a near-prototype scale. To identify the level of reliability of the computed parameters, validation of the pool bottom pressures is carried out by comparison with existing experimental data. The self-similarity of the jet’s centreline velocity is correctly reproduced and the computed maximum dynamic pressures near the stagnation point are reasonably accurate. The differences observed are mainly attributed to the non-consideration of the air phase.
Andreia B. Moreira; Pedro A. Manso; Damien Violeau; Francisco Taveira-Pinto. Single-phase SPH modelling of plunge pool dynamic pressures at a near-prototype scale. Journal of Hydraulic Research 2021, 1 -15.
AMA StyleAndreia B. Moreira, Pedro A. Manso, Damien Violeau, Francisco Taveira-Pinto. Single-phase SPH modelling of plunge pool dynamic pressures at a near-prototype scale. Journal of Hydraulic Research. 2021; ():1-15.
Chicago/Turabian StyleAndreia B. Moreira; Pedro A. Manso; Damien Violeau; Francisco Taveira-Pinto. 2021. "Single-phase SPH modelling of plunge pool dynamic pressures at a near-prototype scale." Journal of Hydraulic Research , no. : 1-15.
Située à la confluence de deux cours d'eau – la Limmat et la Sihl – la ville de Zurich a toujours dû faire face aux crues. Suite aux crues de 2005, un projet de dérivation de la Sihl vers le lac de Zurich en amont de la ville a été lancé. En alternative à un premier projet de galerie de décharge de la Sihl, qui ne contribue qu'à la protection contre les crues, la dérivation de débits par l'aménagement hydroélectrique de pompage-turbinage existant sur le bassin versant présente l'avantage d'une synergie novatrice entre deux objectifs : la protection contre les crues, d'une part, et le réaménagement d'une infrastructure de production d'énergie renouvelable avec augmentation de la puissance installée, d'autre part. Le concept consiste à gérer le niveau du lac d'accumulation de l'aménagement situé sur la Sihl à l'amont de Zurich en tenant compte des prévisions météorologiques afin de laminer les crues tout en produisant de l'énergie hydraulique. La réalisation d'abaissements anticipés du plan d'eau à l'annonce de crues doit néanmoins respecter le règlement de contrôle des niveaux du lac de la Sihl, situé sur un bassin versant très peuplé. La performance de cette solution est fortement liée à la fiabilité des prévisions météorologiques et hydrométriques. Pour augmenter l'effet protecteur de l'aménagement, une augmentation de la puissance équipée de l'aménagement doit être envisagée. Cet article présente une étude hydrologique du bassin versant avec l'accent sur l'analyse des crues, dans l'objectif de déterminer la contribution de différents débits d'équipement de la centrale d'Etzelwerk à la protection de la ville de Zurich lors de crues de périodes de retour de 300 à 500 ans. Le modèle de simulation Routing System du bassin versant est établi et calé sur 32 années complètes, comportant des événements de crue importants. Ensuite, des cas de charge de précipitations de périodes de retour 100, 300 et 1000 ans sont générés comme entrées pour la simulation d'événements de crue. En fin de compte, un débit d'équipement de 147 m3/s, soit quatre fois la capacité actuelle, est finalement retenu comme le débit minimal qui remplirait les exigences de protection contre les crues à Zurich, ce qui correspond à une puissance installée de 600 MW. Located at the confluence of two rivers, the Limmat and the Sihl, the city of Zurich has always faced the risks posed by flood events. Following the 2005 flood event, a tunnel project was launched to partly divert flood water from the Sihl to Lake Zurich upstream of the city centre. As an alternative to such a diversion tunnel, the diversion of excess flood water through the 80-year-old existing Etzelwerk pumped-storage scheme would present the advantage of a synergy between two objectives: enhanced flood protection on the one hand and the rehabilitation of renewable energy production infrastructure with an increase in installed capacity on the other. The concept consists in managing the water levels of the upstream reservoir on the Sihl upstream of Zurich, as function of meteorological and river flow forecasts. Flood routing and flood peak attenuation are obtained through the preventive drawdown of the upper reservoir, whilst producing hydropower. Reservoir drawdown must however respect stringent rules of water level variation, given its location in a densely populated catchment. The performance of the concept is highly dependent on the reliability of the weather and river flow forecasts. The main consequence is an increase in the rated discharge and installed capacity at the Etzelwerk powerplant, justified by its contribution to flood protection. The paper presents the hydrological and hydraulic flood routing studies carried out to assess the performance of different powerhouse discharges in protecting Zurich from floods with return periods between 300 and 500 years. A Routing System model of the watershed was prepared and calibrated over a period of 32 years including major flood events of recent years. Using rainfall load cases of 100, 300 and 1000 years return period, different flood events were produced and routed through the system considering different powerhouse equipment discharge. As a result, a discharge of 147 m3/s (four times more than the present discharge), was identified as the minimum discharge fulfilling the required reduction of the flood risk level in Zurich, leading to an installed capacity for the Etzelwerk scheme of 600 MW.
Guillaume Kayser; Fränz Zeimetz; Pedro Manso; Anton Schleiss; Frédéric Jordan. Synergies entre la production hydroélectrique et la protection contre les crues : cas d'étude de la Sihl en Suisse. La Houille Blanche 2019, 105, 102 -115.
AMA StyleGuillaume Kayser, Fränz Zeimetz, Pedro Manso, Anton Schleiss, Frédéric Jordan. Synergies entre la production hydroélectrique et la protection contre les crues : cas d'étude de la Sihl en Suisse. La Houille Blanche. 2019; 105 (3-4):102-115.
Chicago/Turabian StyleGuillaume Kayser; Fränz Zeimetz; Pedro Manso; Anton Schleiss; Frédéric Jordan. 2019. "Synergies entre la production hydroélectrique et la protection contre les crues : cas d'étude de la Sihl en Suisse." La Houille Blanche 105, no. 3-4: 102-115.
This paper presents a comprehensive methodology to model and determine the annual sediment balance of a complex system of interconnected reservoirs, based on the detailed interpretation of a multi-decadal data series of reservoir management and modelling of sediment fluxes. This methodology is applied to the reservoirs of Oberaar, Grimsel, Räterichsboden, and Trift, which are located in the Swiss Alps. Additionally, the effects of climate warming on the annual sediment yield are investigated. Modelling results show that at present, the hydropower cascade formed by Oberaar, Grimsel, and Räterichsboden retains about 92% of the annual sediment yield, of which only the finest fraction leaves the system and enters the river network. Very fine sediments (d < 10 μm) account for 28% of the total sedimentation rate and in the case of Oberaar, it can reach up to 46% of the total sedimentation rate. Under a climate warming scenario, both sediment yield and runoff are expected to increase in terms of the annual average throughout the XXIst century, which will likely lead to greater annual inputs of sediments to the reservoirs. This, in turn, will lead to a higher sedimentation rate and suspended sediment concentration in the reservoirs, unless active management of the sediment fluxes is implemented.
Sebastián Guillén-Ludeña; Pedro A. Manso; Anton J. Schleiss. Multidecadal Sediment Balance Modelling of a Cascade of Alpine Reservoirs and Perspectives Based on Climate Warming. Water 2018, 10, 1759 .
AMA StyleSebastián Guillén-Ludeña, Pedro A. Manso, Anton J. Schleiss. Multidecadal Sediment Balance Modelling of a Cascade of Alpine Reservoirs and Perspectives Based on Climate Warming. Water. 2018; 10 (12):1759.
Chicago/Turabian StyleSebastián Guillén-Ludeña; Pedro A. Manso; Anton J. Schleiss. 2018. "Multidecadal Sediment Balance Modelling of a Cascade of Alpine Reservoirs and Perspectives Based on Climate Warming." Water 10, no. 12: 1759.
The present review paper aims at collecting and discussing the research work, numerical and experimental, carried out in the field of Fluid–Structure Interaction (FSI) in one-dimensional (1D) pressurized transient flow in the time-domain approach. Background theory and basic definitions are provided for the proper understanding of the assessed literature. A novel frame of reference is proposed for the classification of FSI models based on pipe degrees-of-freedom. Numerical research is organized according to this classification, while an extensive review on experimental research is presented by institution. Engineering applications of FSI models are described and historical accidents and post-accident analyses are documented.
David Ferras; Pedro A. Manso; Anton J. Schleiss; Dídia I. C. Covas. One-Dimensional Fluid–Structure Interaction Models in Pressurized Fluid-Filled Pipes: A Review. Applied Sciences 2018, 8, 1844 .
AMA StyleDavid Ferras, Pedro A. Manso, Anton J. Schleiss, Dídia I. C. Covas. One-Dimensional Fluid–Structure Interaction Models in Pressurized Fluid-Filled Pipes: A Review. Applied Sciences. 2018; 8 (10):1844.
Chicago/Turabian StyleDavid Ferras; Pedro A. Manso; Anton J. Schleiss; Dídia I. C. Covas. 2018. "One-Dimensional Fluid–Structure Interaction Models in Pressurized Fluid-Filled Pipes: A Review." Applied Sciences 8, no. 10: 1844.
Reservoir sedimentation is a major concern in the operational management of dams and appurtenant structures. The increasing volume of sediments deposited in reservoirs leads to a loss of water storage, undermining the purpose itself of the dam for human use or protection. The deposition of sediments (mostly fine) in the vicinity of the dam’s operational structures, such as bottom outlets and power intakes, may result in partial or total blockage of these structures. To cope with these problems, it is essential to determine the sediment balance of the reservoirs, by assessing the origin and quantity of the in- and out-fluxes of sediments. This paper presents a methodology to determine the annual sediment balance of a system of interlinked reservoirs across several decades, as well as its application to the alpine hydropower cascade formed by the Oberaar, Grimsel and Räterichsboden reservoirs located in Switzerland. At that aim, the annual sediment fluxes and the sedimentation rates of each reservoir were characterized. Also, the percentage of fine sediments (dm < 10 μm) included in the total sedimentation rate was estimated. The results reveal that the annual sedimentation rate of the lowermost reservoir of the system (Räterichsboden) is highly altered by the flushing operations of the reservoir upstream (Grimsel). Also, for the uppermost reservoir of the system (Oberaar), the volume of fine sediments deposited annually can reach up to 46% of the total sedimentation rate.
Sebastián Guillén Ludeña; Pedro Manso; Anton J. Schleiss; Benno Schwegler; Jan Stamm; Andres Fankhauser. Sediment balance of a cascade of alpine reservoirs based on multi-decadal data records. E3S Web of Conferences 2018, 40, 03012 .
AMA StyleSebastián Guillén Ludeña, Pedro Manso, Anton J. Schleiss, Benno Schwegler, Jan Stamm, Andres Fankhauser. Sediment balance of a cascade of alpine reservoirs based on multi-decadal data records. E3S Web of Conferences. 2018; 40 ():03012.
Chicago/Turabian StyleSebastián Guillén Ludeña; Pedro Manso; Anton J. Schleiss; Benno Schwegler; Jan Stamm; Andres Fankhauser. 2018. "Sediment balance of a cascade of alpine reservoirs based on multi-decadal data records." E3S Web of Conferences 40, no. : 03012.
The present review paper aims at collecting and discussing the research work, numerical and experimental, carried out in the field of Fluid-Structure Interaction (FSI) in one-dimensional (1D) pressurized transient flow in the time-domain approach. Background theory and basic definitions are provided for the proper understanding of the assessed literature. A novel frame of reference is proposed for the classification of FSI models based on pipe degrees-of-freedom. Numerical research is organized according to this classification, while an extensive review on experimental research is presented by institution. Engineering applications of FSI models are described and historical accidents and post-accident analyses documented.
David Ferras; Pedro A. Manso; Anton J. Schleiss; Dídia I. C. Covas. Fluid-Structure Interaction Models in Pressurized Fluid-Filled Pipes: A Review. 2018, 1 .
AMA StyleDavid Ferras, Pedro A. Manso, Anton J. Schleiss, Dídia I. C. Covas. Fluid-Structure Interaction Models in Pressurized Fluid-Filled Pipes: A Review. . 2018; ():1.
Chicago/Turabian StyleDavid Ferras; Pedro A. Manso; Anton J. Schleiss; Dídia I. C. Covas. 2018. "Fluid-Structure Interaction Models in Pressurized Fluid-Filled Pipes: A Review." , no. : 1.
The prospect of a renewable transition seems plausible for many countries, but can be shrouded in risks, costs and challenges. This paper illuminates a path for such a transition with a numerical investigation, aimed at resolving the power dynamics of a country powered only by renewable generators. The focus was Switzerland, with its considerable hydropower infrastructure and plans to phase out nuclear energy. The model uses optimal power flow calculations to compute the transmission of electricity, and also accounts for the movement of water within the hydropower system. Results suggest that the renewable goal is attainable and will not require radical re-building of the country's transmission infrastructure. Under our assumptions, it was found that the transmission grid is placed under slightly lower stress on average, in renewable scenarios. Despite matching supply and demand on average, the fully renewable system required a ∼107% increase in electrical exchange with neighbouring countries to compensate for seasonal variability, and additional intermittency of electrical supply. Simulation results are described for three scenarios: Current, Intermediate, and Renewable. The bulk power statistics, temporal dynamics, distributions of line use, and spatial patterns are presented, and the implications of the results are discussed.
Stuart Bartlett; Jérôme Dujardin; Annelen Kahl; Bert Kruyt; Pedro Manso; Michael Lehning. Charting the course: A possible route to a fully renewable Swiss power system. Energy 2018, 163, 942 -955.
AMA StyleStuart Bartlett, Jérôme Dujardin, Annelen Kahl, Bert Kruyt, Pedro Manso, Michael Lehning. Charting the course: A possible route to a fully renewable Swiss power system. Energy. 2018; 163 ():942-955.
Chicago/Turabian StyleStuart Bartlett; Jérôme Dujardin; Annelen Kahl; Bert Kruyt; Pedro Manso; Michael Lehning. 2018. "Charting the course: A possible route to a fully renewable Swiss power system." Energy 163, no. : 942-955.
High elevation or high latitude hydropower production (HP) strongly relies on water resources that are influenced by glacier melt and are thus highly sensitive to climate warming. Despite of the wide-spread glacier retreat since the development of HP infrastructure in the 20th century, little quantitative information is available about the role of glacier mass loss for HP. In this paper, we provide the first regional quantification for the share of Alpine hydropower production that directly relies on the waters released by glacier mass loss, i.e. on the depletion of long-term ice storage that cannot be replenished by precipitation in the coming decades. Based on the case of Switzerland (which produces over 50% of its electricity from hydropower), we show that since 1980, 3.0%–4.0% (1.0–1.4 TWh yr−1) of the country-scale hydropower production was directly provided by the net glacier mass loss and that this share is likely to reduce substantially by 2040–2060. For the period 2070–2090, a production reduction of about 1.0 TWh yr−1 is anticipated. The highlighted strong regional differences, both in terms of HP share from glacier mass loss and in terms of timing of production decline, emphasize the need for similar analyses in other Alpine or high latitude regions.
Bettina Schaefli; Pedro Manso; Mauro Fischer; Matthias Huss; Daniel Farinotti. The role of glacier retreat for Swiss hydropower production. Renewable Energy 2018, 132, 615 -627.
AMA StyleBettina Schaefli, Pedro Manso, Mauro Fischer, Matthias Huss, Daniel Farinotti. The role of glacier retreat for Swiss hydropower production. Renewable Energy. 2018; 132 ():615-627.
Chicago/Turabian StyleBettina Schaefli; Pedro Manso; Mauro Fischer; Matthias Huss; Daniel Farinotti. 2018. "The role of glacier retreat for Swiss hydropower production." Renewable Energy 132, no. : 615-627.
The study of a macro-roughness lining system for protection of earth embankment dams during overflow is presented. The system consists of pre-cast concrete elements placed on a drainage/separation layer. Their stability concept is based on the self-weight of the blocks. Several types of elements were developed and tested for stability in a physical model for a typical dam slope of 1/3 (V/H). Based on the experimental results, a stability model was developed to compute the design safety factor for the surface protection lining. Synoptic design charts were derived for 1/3 dam slopes, allowing the rapid estimate of the lining characteristics, as dimensions and weight, for a given design unit discharge and various margins of safety. This macro-roughness lining system is envisaged for spillway rehabilitation of existing dams, for the design and construction of dams less than 30 m high, as well as for the protection of cofferdams.
Pedro A. Manso; Anton J. Schleiss. Improvement of embankment dam safety against overflow by downstream face concrete macro-roughness linings. Dam Maintenance and Rehabilitation 2017, 459 -468.
AMA StylePedro A. Manso, Anton J. Schleiss. Improvement of embankment dam safety against overflow by downstream face concrete macro-roughness linings. Dam Maintenance and Rehabilitation. 2017; ():459-468.
Chicago/Turabian StylePedro A. Manso; Anton J. Schleiss. 2017. "Improvement of embankment dam safety against overflow by downstream face concrete macro-roughness linings." Dam Maintenance and Rehabilitation , no. : 459-468.
Cécile Bousquet; Irene Samora; Pedro Manso; Luca Rossi; Philippe Heller; Anton J. Schleiss. Assessment of hydropower potential in wastewater systems and application to Switzerland. Renewable Energy 2017, 113, 64 -73.
AMA StyleCécile Bousquet, Irene Samora, Pedro Manso, Luca Rossi, Philippe Heller, Anton J. Schleiss. Assessment of hydropower potential in wastewater systems and application to Switzerland. Renewable Energy. 2017; 113 ():64-73.
Chicago/Turabian StyleCécile Bousquet; Irene Samora; Pedro Manso; Luca Rossi; Philippe Heller; Anton J. Schleiss. 2017. "Assessment of hydropower potential in wastewater systems and application to Switzerland." Renewable Energy 113, no. : 64-73.
A.J. Pachoud; P.A. Manso; A.J. Schleiss. Stress intensity factors for axial semi-elliptical surface cracks and embedded elliptical cracks at longitudinal butt welded joints of steel-lined pressure tunnels and shafts considering weld shape. Engineering Fracture Mechanics 2017, 179, 93 -119.
AMA StyleA.J. Pachoud, P.A. Manso, A.J. Schleiss. Stress intensity factors for axial semi-elliptical surface cracks and embedded elliptical cracks at longitudinal butt welded joints of steel-lined pressure tunnels and shafts considering weld shape. Engineering Fracture Mechanics. 2017; 179 ():93-119.
Chicago/Turabian StyleA.J. Pachoud; P.A. Manso; A.J. Schleiss. 2017. "Stress intensity factors for axial semi-elliptical surface cracks and embedded elliptical cracks at longitudinal butt welded joints of steel-lined pressure tunnels and shafts considering weld shape." Engineering Fracture Mechanics 179, no. : 93-119.
The paper presents the analysis of fluid–structure interaction occurring during hydraulic transients in pipe coils by means of a four-equation model. The purpose is to understand and describe the effect of the coil movement on the transient wave. The four-equation model couples the transient pipe flow with the axial movement of the pipe-wall neglecting radial inertia, flexure and torsion of the piping system. Three models have been developed: the first simplifying the coil to a straight pipe with a moving valve, the second model assuming independent axial deformation in each coil ring, and the third model that includes dry friction dissipation. The first allows an easier generalization of the method; however, it does not allow the complete description of the phenomenon; the second and third models fit better the experimental observations in the pipe coil facility, suggesting that its behaviour is dominated by the independent movement of the rings.
D. Ferras; P. A. Manso; D. I. C. Covas; A. J. Schleiss. Fluid–structure interaction in pipe coils during hydraulic transients. Journal of Hydraulic Research 2017, 55, 491 -505.
AMA StyleD. Ferras, P. A. Manso, D. I. C. Covas, A. J. Schleiss. Fluid–structure interaction in pipe coils during hydraulic transients. Journal of Hydraulic Research. 2017; 55 (4):491-505.
Chicago/Turabian StyleD. Ferras; P. A. Manso; D. I. C. Covas; A. J. Schleiss. 2017. "Fluid–structure interaction in pipe coils during hydraulic transients." Journal of Hydraulic Research 55, no. 4: 491-505.
This investigation aims at assessing the fluid-structure interaction (FSI) occurring during hydraulic transients in straight pipeline systems fixed to anchor blocks. A two mode 4-equation model is implemented incorporating the main interacting mechanisms: Poisson, friction and junction coupling. The resistance to movement due to inertia and dry friction of the anchor blocks is treated as junction coupling. Unsteady skin friction is taken into account in friction coupling. Experimental waterhammer tests collected from a straight copper pipe-rig are used for model validation in terms of wave shape, timing and damping. Numerical results successfully reproduce laboratory measurements for realistic values of calibration parameters. The novelty of this paper is the presentation of a 1D FSI solver capable of describing the resistance to movement of anchor blocks and its effect on the transient pressure wave propagation in straight pipelines.
David Ferras; Pedro A. Manso; Anton J. Schleiss; Dídia Isabel Cameira Covas. Fluid-structure interaction in straight pipelines with different anchoring conditions. Journal of Sound and Vibration 2017, 394, 348 -365.
AMA StyleDavid Ferras, Pedro A. Manso, Anton J. Schleiss, Dídia Isabel Cameira Covas. Fluid-structure interaction in straight pipelines with different anchoring conditions. Journal of Sound and Vibration. 2017; 394 ():348-365.
Chicago/Turabian StyleDavid Ferras; Pedro A. Manso; Anton J. Schleiss; Dídia Isabel Cameira Covas. 2017. "Fluid-structure interaction in straight pipelines with different anchoring conditions." Journal of Sound and Vibration 394, no. : 348-365.
A.J. Pachoud; Pedro Manso; A.J. Schleiss. New parametric equations to estimate notch stress concentration factors at butt welded joints modeling the weld profile with splines. Engineering Failure Analysis 2017, 72, 11 -24.
AMA StyleA.J. Pachoud, Pedro Manso, A.J. Schleiss. New parametric equations to estimate notch stress concentration factors at butt welded joints modeling the weld profile with splines. Engineering Failure Analysis. 2017; 72 ():11-24.
Chicago/Turabian StyleA.J. Pachoud; Pedro Manso; A.J. Schleiss. 2017. "New parametric equations to estimate notch stress concentration factors at butt welded joints modeling the weld profile with splines." Engineering Failure Analysis 72, no. : 11-24.
Small-scale hydropower is emerging as a decentralized source to satisfy local demand for electricity. In water supply systems, microhydropower can be used for energy recovery associated with excessive pressure control. However, there is a lack of specific solutions for applications within networks where discharges are highly variable and there are limitations of pressure. An arrangement of microturbines specially conceived for water supply networks is proposed, based on a recently tested microturbine for inline installation in pipes. The installation of up to four turbine units is possible within a buried chamber created around an existing pipe. The location of the chambers is analyzed using an optimization algorithm that considers two objective functions: energy production and economic value. The feasibility of the proposed arrangement for a microhydropower plant was assessed through a case study of a subgrid of the water supply network of Lausanne, Switzerland. A detailed analysis of the cost breakdown revealed that further to the electromechanical equipment, the number of isolation valves required in each layout may have an important role on the investments.
Irene Samora; Pedro Manso; Mário J. Franca; Anton J. Schleiss; Helena M. Ramos. Opportunity and Economic Feasibility of Inline Microhydropower Units in Water Supply Networks. Journal of Water Resources Planning and Management 2016, 142, 04016052 .
AMA StyleIrene Samora, Pedro Manso, Mário J. Franca, Anton J. Schleiss, Helena M. Ramos. Opportunity and Economic Feasibility of Inline Microhydropower Units in Water Supply Networks. Journal of Water Resources Planning and Management. 2016; 142 (11):04016052.
Chicago/Turabian StyleIrene Samora; Pedro Manso; Mário J. Franca; Anton J. Schleiss; Helena M. Ramos. 2016. "Opportunity and Economic Feasibility of Inline Microhydropower Units in Water Supply Networks." Journal of Water Resources Planning and Management 142, no. 11: 04016052.
The aim of the present paper is to contribute to the identification of the principal mechanical–hydraulical relationships during hydraulic transients by means of the analysis of observed transient pressure and strain waves in different pipe rigs. Four different experimental set-ups are analysed: a straight copper pipe with either moving or anchored downstream pipe-end, a coil copper pipe and a coil polyethylene pipe. Discussion highlights differences in the response of each system in terms of wave shape, damping, and dispersion. The straight copper pipe behaviour, for an anchored pipe-end, has shown the closest dynamic response to the expected one from classical waterhammer theory, being unsteady friction the most relevant damping mechanism. Fluid structure interaction dominates when the valve is released in the straight copper pipe and also has an important role in the coil copper pipe. Viscoelasticity dominates in the polyethylene pipe.
David Ferràs; Pedro A. Manso; Anton J. Schleiss; Dídia Isabel Cameira Covas. Experimental distinction of damping mechanisms during hydraulic transients in pipe flow. Journal of Fluids and Structures 2016, 66, 424 -446.
AMA StyleDavid Ferràs, Pedro A. Manso, Anton J. Schleiss, Dídia Isabel Cameira Covas. Experimental distinction of damping mechanisms during hydraulic transients in pipe flow. Journal of Fluids and Structures. 2016; 66 ():424-446.
Chicago/Turabian StyleDavid Ferràs; Pedro A. Manso; Anton J. Schleiss; Dídia Isabel Cameira Covas. 2016. "Experimental distinction of damping mechanisms during hydraulic transients in pipe flow." Journal of Fluids and Structures 66, no. : 424-446.
Water supply systems (WWSs) are one of the main manmade water infrastructures presenting potential for micro-hydropower. Within urban networks, local decentralized micro-hydropower plants (MHPs) may be inserted in the regional electricity grid or used for self-consumption at the local grid level. Nevertheless, such networks are complex and the quantification of the potential for micro-hydropower other than that achieved by replacing pressure reducing valves (PRVs) is difficult. In this work, a methodology to quantify the potential for hydropower based on the excess energy in a network is proposed and applied to a real case. A constructive solution is presented based on the use of a novel micro-turbine for energy conversion, the five blade tubular propeller (5BTP). The location of the MHP within the network is defined with an optimization algorithm that maximizes the net present value after 20 years of operation. These concepts are tested for the WSS in the city of Fribourg, Switzerland. The proposed solution captures 10% of the city’s energy potential and represents an economic interest. The results confirm the location of PRVs as potential sites for energy recovery and stress the need for careful sensitivity analysis of the consumption. Finally, an expedited method is derived to estimate the costs and energy that one 5BTP can produce in a given network.
Irene Samora; Pedro Manso; Mário J. Franca; Anton J. Schleiss; Helena M. Ramos. Energy Recovery Using Micro-Hydropower Technology in Water Supply Systems: The Case Study of the City of Fribourg. Water 2016, 8, 344 .
AMA StyleIrene Samora, Pedro Manso, Mário J. Franca, Anton J. Schleiss, Helena M. Ramos. Energy Recovery Using Micro-Hydropower Technology in Water Supply Systems: The Case Study of the City of Fribourg. Water. 2016; 8 (8):344.
Chicago/Turabian StyleIrene Samora; Pedro Manso; Mário J. Franca; Anton J. Schleiss; Helena M. Ramos. 2016. "Energy Recovery Using Micro-Hydropower Technology in Water Supply Systems: The Case Study of the City of Fribourg." Water 8, no. 8: 344.
The present paper approaches fluid-structure interaction by means of a 4-equation model. Experimental data collected from a straight copper pipe-rig lying directly on the lab floor is used for the model validation in terms of wave shape, timing and damping. The main focus lies on the friction coupling modelling considering skin and dry friction. For skin friction three approaches are analysed: quasi-steady, Brunone’s and Trikha’s unsteady friction. For dry friction Coulomb’s model is added in the beam momentum conservation equation. Results present a good fitting between experimental and numerical data, showing the dissipative effect of dry friction phenomenon which complement that of skin friction, specially in the short term simulation.
David Ferràs; Pedro A. Manso; Anton J. Schleiss; Dídia Isabel Cameira Covas. Fluid-structure interaction in straight pipelines: Friction coupling mechanisms. Computers & Structures 2016, 175, 74 -90.
AMA StyleDavid Ferràs, Pedro A. Manso, Anton J. Schleiss, Dídia Isabel Cameira Covas. Fluid-structure interaction in straight pipelines: Friction coupling mechanisms. Computers & Structures. 2016; 175 ():74-90.
Chicago/Turabian StyleDavid Ferràs; Pedro A. Manso; Anton J. Schleiss; Dídia Isabel Cameira Covas. 2016. "Fluid-structure interaction in straight pipelines: Friction coupling mechanisms." Computers & Structures 175, no. : 74-90.
Using high-strength steels for pressure shafts and tunnel liners and taking into account significant rock mass participation allows the design of comparatively thin steel liners in hydropower projects. Nevertheless, during emptying of waterways, these steel linings may be endangered by buckling. Compared with traditional measures such as increased steel liner thickness and stiffeners, pressure relief valves are a very economical solution for protection of steel liners against critical external pressure and therefore buckling during emptying. A calculation procedure has been developed for the design of the required number and arrangement of pressure relief valves, and this has been used successfully in practice. Systematic model tests enabled the assumptions of the design method to be verified.
Anton J. Schleiss; Pedro Manso. Design of Pressure Relief Valves for Protection of Steel-Lined Pressure Shafts and Tunnels Against Buckling During Emptying. Rock Mechanics and Rock Engineering 2011, 45, 11 -20.
AMA StyleAnton J. Schleiss, Pedro Manso. Design of Pressure Relief Valves for Protection of Steel-Lined Pressure Shafts and Tunnels Against Buckling During Emptying. Rock Mechanics and Rock Engineering. 2011; 45 (1):11-20.
Chicago/Turabian StyleAnton J. Schleiss; Pedro Manso. 2011. "Design of Pressure Relief Valves for Protection of Steel-Lined Pressure Shafts and Tunnels Against Buckling During Emptying." Rock Mechanics and Rock Engineering 45, no. 1: 11-20.
The geometrical development of unlined plunge pools downstream large dams depends on both local geology and type of plunging jet and its diffusion pattern. Experimental investigations in plunge pools with different lateral confinements are presented. They show that the pool geometry influences plunging jet diffusion, air entrainment in the pool, and, as a consequence, impact pressures at the water-rock interface and inside the fissured rock mass. Results include impact pressures definition for variable pool depths, jet velocities, and pool geometries, depending explicitly on the lateral confinement of the jet. The main pool flow features are described focusing on their contribution to energy dissipation. Should the lateral confinement limit the development of macroturbulent rollers around the plunging jet (instead of the pool depth), the mean pressures at impact are considerably reduced, as well as RMS pressures in transitional and deep pools. For shallow pools, RMS pressures increase as a result of enhanced jet development.
Pedro Manso; Erik F. R. Bollaert; Anton J. Schleiss. Influence of Plunge Pool Geometry on High-Velocity Jet Impact Pressures and Pressure Propagation inside Fissured Rock Media. Journal of Hydraulic Engineering 2009, 135, 783 -792.
AMA StylePedro Manso, Erik F. R. Bollaert, Anton J. Schleiss. Influence of Plunge Pool Geometry on High-Velocity Jet Impact Pressures and Pressure Propagation inside Fissured Rock Media. Journal of Hydraulic Engineering. 2009; 135 (10):783-792.
Chicago/Turabian StylePedro Manso; Erik F. R. Bollaert; Anton J. Schleiss. 2009. "Influence of Plunge Pool Geometry on High-Velocity Jet Impact Pressures and Pressure Propagation inside Fissured Rock Media." Journal of Hydraulic Engineering 135, no. 10: 783-792.