Nonlinear Truss-Based Quasi-Static Structural Model for Force Distribution Predictions on Debris Containment Grids

2018 ◽  
Author(s):  
Jose Rodolfo Chreim ◽  
Joao Lucas Dozzi Dantas ◽  
Alessandro Alberto de Lima
Keyword(s):  
Power Plant ◽  
Structural Model ◽  
Free Stream ◽  
Hydroelectric Power Plant ◽  
Nonlinear Finite Element ◽  
Normal Operation ◽  
Natural Phenomenon ◽  
Hydroelectric Power ◽  
Nonlinear Finite Element Method ◽  
Madeira River

At the Madeira River, north of Brazil, a natural phenomenon threatens the integrity and normal operation of an on-site hydroelectric power plant; thus, assemblies of containment structures, called logbooms, are installed across the river in order to protect the power plant installations. A truss-based nonlinear finite element method numerical tool is developed with the objective of designing and analyzing these assemblies. Initially, only the influence of the upstream velocity field is considered, and future modifications to account for the debris are expected. Code and solution verifications show that the tool converges reasonably well; the numerical error is about 0.2% of the theoretical value, and the uncertainty is about the same order: the results agree with analytical solutions from the simple catenary model. Finally, the method is validated by comparing numerical and experimental data; a satisfactory agreement is obtained, ascertaining the accuracy of the method: differences between experimental and numerical results are no higher than 6% and the trend of the tension force as a function of the free stream is followed by the numerical method.

scholarly journals Dataset of long-term monitoring of ground-dwelling ants (Hymenoptera: Formicidae) in the influence areas of a hydroelectric power plant on the Madeira River in the Amazon Basin

2018 ◽  
Vol 6 ◽  
pp. e24375 ◽  
Author(s):  
Itanna Fernandes ◽  
Jorge de Souza
Keyword(s):  
Power Plant ◽  
Amazon Basin ◽  
Hydroelectric Power Plant ◽  
Biodiversity Loss ◽  
Hydroelectric Power ◽  
Natural Ecosystems ◽  
Influence Area ◽  
Before And After ◽  
Madeira River ◽  
The Impact

Biodiversity loss is accelerating rapidly in response to increasing human influence on the Earth’s natural ecosystems. One way to overcome this problem is by focusing on places of human interest and monitoring the changes and impacts on the biodiversity. This study was conducted at six sites within the influence area of the Santo Antônio Hydroelectric Power Plant in the margins of the Madeira River in Rondônia State. The sites cover a latitudinal gradient of approximately 100 km in the Brazilian Amazon Basin. The sampling design included six sampling modules with six plots (transects) each, totaling 30 sampling plots. The transects were distributed with 0 km, 0.5 km, 1 km, 2 km, 3 km and 4 km, measured perpendicularly from the river margin towards the interior of the forest. For sampling the ground-dwelling ants, the study used the ALL (ants of the leaf litter) protocol, which is standardized globally in the inventories of ant fauna. For the purpose of impact indicators, the first two campaigns (September 2011 to November 2011) were carried out in the pre-filling period, while campaigns 3 to 10 (February 2012 to November 2014) were carried out during and after the filling of the hydroelectric reservoir. A total of 253 events with a total of 9,165 occurrences were accounted during the monitoring. The ants were distributed in 10 subfamilies, 68 genera and 324 species/morphospecies. The impact on ant biodiversity during the periods before and after filling was measured by ecological indicators and by the presence and absence of some species/morphospecies. This is the first study, as far as we know, including taxonomic and ecological treatment to monitor the impact of a hydroelectric power plant on ant fauna. Until recently, most studies conducted on hydroelectric plants, located in the Amazon Basin, were carried out after the implementation of dams in order to assess their impacts on the environment and biodiversity (Benchimol and Peres 2015, Latrubesse et al. 2017, Sá-Oliveira et al. 2015). Recent studies on dam impacts have begun to be conducted prior to dam implementation (e.g. Bobrowiec and Tavares 2017, Fraga et al. 2014, Moser et al. 2014), thus providing a better overview of the impact and a better assessment of its magnitude.

CFD Simulation of the Submerged Cofferdams Effect on the Operation of the Future Tocoma Hydroelectric Power Plant

2009 ◽  
Author(s):  
Milan Stanko ◽  
Andrea Shmueli ◽  
Miguel Asuaje ◽  
Frank Kenyery ◽  
Gonzalo Montilla ◽  
...  
Keyword(s):  
Power Plant ◽  
Velocity Profile ◽  
Cfd Simulation ◽  
Numerical Study ◽  
Computational Cost ◽  
Hydroelectric Power Plant ◽  
Normal Operation ◽  
Hydroelectric Power ◽  
Uniform Velocity ◽  
Operation Conditions

The Tocoma hydroelectric power plant, currently under construction, is located on the lower basin of the Caroni River in Bolivar State in Venezuela. This power plant will have 10 Kaplan turbines in its powerhouse that will generate approximately 2160 MW of hydroelectric power. During its construction, two cofferdams designated “A” and “B” will be built and afterwards will remain submerged. The main purpose of this experimental-numerical study is to analyze the possible future hydrodynamic effects of these structures on the operation of the Kaplan turbines. The presence of the submerged cofferdams could originate tridimensional hydrodynamic behaviors that could produce energy looses and operational and functional problems to the turbines. Two mathematical steady state single phase models using Computational Fluid Dynamics (CFD) Techniques and applying the commercial software ANSYS-CFX were developed. The first model represented the hydroelectric power plant reservoir that was quantitatively and qualitatively calibrated with a Froude Similarity 1:80 Scale Physical Model. Hydrodynamic flow patterns near to the intakes were found in the first model. Those patterns showed a non-uniform velocity profile in the unit’s intakes nearest to cofferdam “B”. The second mathematical model represented the study of the intake, the semi-spiral case and the Kaplan turbine. This model considers the non-uniform velocity profile that was found in the first model as an inlet boundary condition. Two methodologies were used to develop this model: one using two simulations with two overlapping physical domains, and the other one using the whole geometry. It was found that using overlapping domains in order to reduce the computational cost of the total simulation is a good way to obtain physical results with fair accuracy. The general results reported that the velocity profile at the intake of the powerhouse does not produce any stationary non uniform behavior on the velocity and pressure profiles in the unit compared to the uniform velocity profile case. This result could be an indicator that the non uniform condition at the intake of the Kaplan Turbines at Tocoma will not affect the normal operation conditions of the unit.

Mercury Exposure Assessment In A Traditional Riparian Community At Madeira River Before A Hydroelectric Power Plant Operation

2015 ◽  
Vol 2015 (1) ◽  
pp. 3185
Author(s):  
Claudia Maribel Vega Ruiz ◽  
Sandra Hacon ◽  
Dennys Morao ◽  
Rodrigo Gonçalves ◽  
Paulo Guimarães Barrocas ◽  
...  
Keyword(s):  
Power Plant ◽  
Exposure Assessment ◽  
Hydroelectric Power Plant ◽  
Mercury Exposure ◽  
Hydroelectric Power ◽  
Plant Operation ◽  
Madeira River ◽  
Power Plant Operation

More Ancient than the Ages

2021 ◽  
Vol 55 ◽  
pp. 223-232
Author(s):  
William McNeill ◽  
Keyword(s):  
Power Plant ◽  
Hydroelectric Power Plant ◽  
Fundamental Question ◽  
Natural Phenomenon ◽  
River Rhine ◽  
Rhine River ◽  
Hydroelectric Power ◽  
Human Beings ◽  
Specific Interpretation ◽  
The Face

The question of the relation, not of technology, but of the “essence” of technology, that is, of technicity (die Technik)—understood in Heidegger’s sense as a destining of revealing—the question of the relation of technicity to nature is becoming ever more urgent. Human beings and their fate are implicated in that relation, yet never as merely passive participants, and they need to be awakened both to that urgency and to the fundamental question it poses: poses to them as those who are implicated in this manner. The question of the relation of technicity to nature arrives on our doorstep today by virtue of a long, philosophical inheritance, one articulated in terms of the relation of phusis and techne. It is a very specific interpretation and appropriation of techne—and also, inseparably, of phusis—that, in the course of the centuries, sets the stage for the emergence of technicity and its relation to nature. Yet the Greek word techne once meant not only the production of items of utility using nature as a resource, but also the bringing forth of the beautiful, or rather, of the experience of the gods—a bringing forth that came to be called art. In his 1953 essay “The Question Concerning Technicity,” Heidegger invites us to reflect on the question of the relation of technicity to nature by considering “the monstrousness” (das Ungeheure) that becomes manifest in the contrast between the Rhine river as dammed up and placed into the service of a hydroelectric power plant, and the Rhine “as uttered by the artwork, in Hölderlin’s hymn by that name.” The contrast, we note, is not between a pure, pristine, unadulterated nature, the river Rhine as a natural phenomenon untouched by techne, and the river placed (gestellt) in the service of technicity. The contrast, rather, is between two ways in which the Rhine can be revealed to us, two ways of letting something be revealed, two modes of techne—techne itself being a mode of revealing, as the essay elucidates. Yet what, then, of phusis, that other mode of revealing? Is it perhaps the case that phusis needs techne, not as a technical supplement in the sense of technicity, but as art, whose essence is poetizing (Dichtung)—needs it in order to show itself in a more primordial, more ancient sense? Must the response that the urgency of the question concerning the relation of technicity to nature elicits from us entail our becoming poets, or at least artists—and this despite the fact that any appeal to art as “the saving power” must seem hopeless in the face of the destinal force that is technicity? My remarks here elaborate on these themes by turning to Heidegger’s reading of Hölderlin’s hymn “Wie wenn am Feiertage…,” where nature is said to be “more ancient than the ages.”

Water Level Control of Small-scale Hydroelectric Power Plant

2002 ◽  
Vol 122 (6) ◽  
pp. 989-994
Author(s):  
Shinichiro Endo ◽  
Masami Konishi ◽  
Hirosuke Imabayashi ◽  
Hayami Sugiyama
Keyword(s):  
Power Plant ◽  
Water Level ◽  
Hydroelectric Power Plant ◽  
Small Scale ◽  
Hydroelectric Power ◽  
Level Control

Hydroelectric Power-Plant Simulator Implemented in Python

2021 ◽  
Author(s):  
Michal Kuchar ◽  
Adam Peichl ◽  
Milan Kucera ◽  
Jaromir Fiser ◽  
Pavel Kulik ◽  
...  
Keyword(s):  
Power Plant ◽  
Hydroelectric Power Plant ◽  
Hydroelectric Power

scholarly journals Dynamics of Lady’s slipper orchid (Cypripedium calceolus L.) population at Lake Kwiecko (West Pomerania)

2014 ◽  
Vol 36 (1) ◽  
pp. 53-60 ◽  
Author(s):  
Maciej Korczyński ◽  
Ewa Krasicka-Korczyńska
Keyword(s):  
Power Plant ◽  
Endangered Species ◽  
Rare Species ◽  
Negative Impact ◽  
Good Condition ◽  
Hydroelectric Power Plant ◽  
Field Observations ◽  
Hydroelectric Power ◽  
Cypripedium Calceolus ◽  
Slipper Orchid

Abstract Cypripedium calceolus is considered an endangered species in the territory of Poland. Population of this rare species, situated at Lake Kwiecko (Western Pomerania), was regularly monitored in the years 1986-2013. The studied population has been under the permanent influence of the nearby hydroelectric power plant for almost 45 years. The field observations showed that the power plant had no negative impact on the condition of Cypripedium calceolus population. An indication of its good condition was, among others, an increase in the size - from 150 to 350 specimens within the study period.

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