Browsing by Author "Pacheco Tobar, Esteban Alonso"

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Análisis comparativo de transitorios en una chimenea de equilibrio con orificio y una chimenea de equilibrio de sección compuesta
(Universidad de Cuenca, 2025-09-24) Villavicencio Fernández, Manuel Alejandro; Reyes Zuña, Doménica Giselle; Pacheco Tobar, Esteban Alonso
This study presents a comparative analysis of the hydraulic behavior of two surge tank configurations—a surge tank with an orifice and a composite-section surge tank—under transient flow conditions caused by sudden valve closures and openings. A numerical-iterative procedure based on the rigid water column model is employed to simulate flow dynamics and piezometric level oscillations within the surge tanks. Both configurations are evaluated through critical scenarios adapted to specific hydraulic conditions, derived from a case study located in Ecuador. The methodology includes the definition of hydraulic and geometric parameters for each surge tank type, accounting for variations in the orifice diameter and the upper widening of the composite section. Key variables associated with transient phenomena, such as water level oscillations, stabilization times, and amplitude of fluctuations during the events, are analyzed. This work aims to provide clear technical criteria for selecting the appropriate surge tank configuration based on the operational characteristics of the hydraulic system and flow conditions, thereby contributing to the efficient and safe design of pressurized conduits in regions with high topographical complexity.
ANÁLISIS DE LA CALIDAD DEL AGUA EN EL SECTOR RURAL DE CUENCA, CASO DE LOS SISTEMAS COMUNITARIOS “CARMEN DEL CONCHÁN” Y “ CONCHAN DEL CISNE” DE LA PARROQUIA DE EL VALLE
(Universidad de Cuenca, 2025-09-25) Carchi Fernández, Wendy Cristina; Peñaloza Ganán, David Herman; Pacheco Tobar, Esteban Alonso
This paper analyzes the water quality and technical condition of the community water supply systems “Carmen del Conchan” and “Cisne del Conchan”, located in the parish of El Valle, canton Cuenca, province of Azuay. Currently, the evaluation of community systems is based on the level of coverage and quantity of water supplied, which generates systems with technical deficiencies, leaving fundamental aspects such as quality in the background. In addition, the urban-rural gap generates neglect in terms of updating and validating information, which delays development processes in rural areas. This paper analyzes the current status of community systems in terms of water quality, i.e., the analysis and evaluation of treatment and disinfection systems, but also of distribution and catchment systems. With this, technical solutions adapted to the conditions of each community are proposed, and with them, the efficiency of filtration systems as a treatment process is evidenced, as well as the importance of making known the need for a disinfection system to improve the conditions of drinking water. Finally, it is identified that the values of endowment established by the current standard in the country tend to be high compared to the results obtained in this study, which leads to the oversizing of the technical solutions in civil works. This situation implies an increase in investment costs for the beneficiary communities. Therefore, it is considered essential to update the information at the rural level for the development of more efficient and sustainable designs in future research and projects.
Análisis de la variación vertical de temperatura en el sistema agua superficial-agua subterranea en el río Cumbe
(2013) Torres Alves, Gina Alexandra; Urgilez Vinueza, Alexandra Rocío; Pacheco Tobar, Esteban Alonso; Guzmán Cárdenas, Pablo
Análisis de transitorios para el diseño o evaluación de una columna piezométrica
(Universidad de Cuenca, 2025-09-24) Torres Delgado, Emily Maritza; Pacheco Tobar, Esteban Alonso
In mountainous areas, hydraulic structures such as galleries, low-head tunnels, and pressure pipelines face significant risks associated with hydraulic transients caused by sudden changes in flow regimes at control points (valves, pumping equipment, and turbines). These changes result in abrupt pressure variations, leading to phenomena such as water hammer and undesirable oscillations. The effects include damage to joints, reverse leaks, structural collapses in tunnels, and fluctuations in reservoir levels. To mitigate these impacts, the design and use of piezometric columns and surge tanks are required. The theoretical framework offers various methodologies and models, both empirical and theoretical, to analyze these phenomena. However, an integration of methodologies and procedures that enable a standardized approach to design and evaluation for projects has not yet been developed. This creates uncertainty in review, evaluation, and alternative selection procedures, impacting the implementation and cost of the works. In this context, based on a review of theoretical aspects and fundamental technical criteria, an evaluation of design procedures and best practices for sizing piezometric columns and surge tanks has been proposed. Through the application of a case study, the aim is to contribute to the development of a methodology that standardizes aspects related to review and evaluation.
Análisis numérico del vertedero de excesos para control de crecida en una captación convencional
(Universidad de Cuenca, 2022-02-15) Astudillo García, Mateo José; Vanegas Moncayo, Stefanny Paola; Pacheco Tobar, Esteban Alonso
In hydraulic projects, the projection of structures such as spillways and gates is essential. These structures allow capturing and directing the flow, regulating flows and levels, as well as facilitating operation and maintenance. One of the most used structures, essential for flow control in flood scenarios, is the excess side weir, which, like other adjoining and control works, is normally designed by traditional methods that include important simplifications in relation to a bidirectional behaviour of the flow. In this context, in the present graduation project, the analysis and validation of the traditional design criteria and procedures for a structure used to discharge excess flows through a side weir is proposed for a case study with a flow considered representative for small and medium magnitude structures. The analysis was performed by contrasting the results obtained with OpenFoam a Computational Fluid Dynamics (CFD) software that solves numerically the fluid flow governing equations. The numerical model allowed to obtain a guided simulation of the behaviour of the flow in the vicinity of the excess side weir. As the main result of the present work, and after the comparative analysis between the conventional dimensioning and the numerical flow model results, it is concluded that the empirical-order simplifications used in the conventional design procedures that consider unidirectional flow don’t compromise the accuracy of the representation of the real flow profile. The flow patterns obtained with the numerical model correspond adequately with the flow profile estimated with the conventional procedure. Therefore, important modifications are not required since variations in water levels have values in the order of 1.74%.
Application of the grid convergence index to a laminar axisymmetric sudden expansion flow
(Universidad de Cuenca, 2014) Carrillo Serrano, Verónica Margarita; Petrie, John; Pacheco Tobar, Esteban Alonso
The use of numerical models to represent natural processes is increasingly common. The development of advanced numerical tools allows a more physically-based representation of complex flow phenomena. While more advanced systems can be solved, the uncertainty of the accuracy of the solutions obtained remains. The mere comparison between experiments and simulations is not enough proof of strength of the results. The Grid Convergence Index (GCI) methodology has been proposed with the aim to provide a mechanism to calculate and report discretization errors estimates in computational fluid dynamics (CFD) simulations. It permits the quantification of the uncertainty present in grid convergence. This method uses a grid convergence error estimator that is obtained by applying the generalized Richardson Extrapolation theory. The process is applied to an axisymmetric sudden expansion laminar flow case. Experimental results are used to verify the numerical simulation and GCI outcome. As a result of the application of this method the order of accuracy of the numerical scheme was verified. Additionally, comparing the numerical results with the experimental values, a maximum error of 6% was obtained. Finally, considering the two finest meshes, it can be concluded that the asymptotic range has been reached and that a finer Mesh won’t improve the accuracy of the solution when considering the increased numerical cost.
Caracterización de la carga de lecho en el río Calabí mediante de estudio experimental en canal de laboratorio
(2014) Chacha Cabrera, Byron Rodrigo; Molina Ortiz, Tania Maribel; Pacheco Tobar, Esteban Alonso
Potential bed-load transport rates are determined by an experimental study in a moving-bed physical model. The study was conducted for the Calabí River located on the coast of Ecuador to the "Plan of Development and Control of Water in the province of Los Rios" than is executed through the agreement between the University of Cuenca and the SecretaríaNacionaldel Agua (SENAGUA). This study evaluates the response of the physical model to the processes for incipient movement for specific conditions related to flow and a comparative study of the theoretical rates projected for several equations available in the technical literature is done. The study establishes that the river Calabí presents an armor layers in the gravel bed in reference to diameter d50 than represents the surface material. For material that representing smaller diameters and for the formative flux, the study stablishes a transport rate of 6.61 kg/s/m for the prototype scale.
Caracterización de la carga de sedimentos en suspensión en la microcuenca del Río Tabacay
(2010) Cajas Parra, Daniela Cecilia; Cisneros Espinoza, Felipe Eduardo; Pacheco Tobar, Esteban Alonso
Characterization of bedload sediment transport in high slope rivers using hydraulic geometry theory
(Asce library, 2019) Cisneros Espinoza, Felipe Eduardo ; Petrie, John; Pacheco Tobar, Esteban Alonso; Timbe Castro, Luis Manuel; Carrillo Serrano, Verónica Margarita
In Ecuador, steep rough-bedded channels constitute the main component of mountainous drainage system. They provide sediment to milder-slope downstream channels. Thus, sediment transport represents a driving process in natural drainage system. Namely, it defines river morphology evolution. To quantify and to understand the magnitude and effect of this process in the surrounding environment, the understanding and knowledge of bedload transport must be improved. The study of sediment transport in steeper channels with coarser material is a complex process. The continuously changing environment results in a high uncertainty in the quantification of sediment transport rates. Some equations have been proposed to quantify the rates. However the lack of actual measured data does not allow proper quantification and verification. On the other hand, hydraulic geometry (HG) theory has been applied to generate elements for a consistent monitoring of rivers behavior. Dimensionless HG relations that replicate what is observed in rivers have been obtained. Parameters such as top width, mean flow depth, mean velocity, and suspended sediment load of several gravel-bed rivers have been related with liquid discharge. The present study proposes the characterization of bedload sediment transport of steep gravel-bed rivers in terms of dimensionless HG relations. Measurements in various reaches along a river of bedload transport rate are performed to determine the parameters (exponents and coefficients) of the HG relations. The results represent a contribution that allows the reduction of the lack of field-measured data as well as the application of a theory generally used to characterize hydraulic-geometric parameters to characterize bedload sediment transport.
Determinación experimental de las variables asociadas al control de flujo a través de un modelo físico, en un cuenco de disipación de energía tipo SAF de la derivadora Cañar
(2011) Calle Barahona, Edison Fernando; Domínguez Quinteros, Juan Patricio; Pacheco Tobar, Esteban Alonso
Determinación experimental de las variables asociadas al control de flujo en modelo físico para los caudales de diseño en la estructura de compuerta de la derivadora Cañar
(2011) Tinoco Ochoa, José Vicente; Cisneros Espinoza, Felipe Eduardo; Pacheco Tobar, Esteban Alonso
Diseño de un módulo experimental para riego tecnificado para el gobierno provincial
(Universidad de Cuenca, 2025-04-09) Rivadeneira Hermida, Jocelyne Marilú; Torres Villa, Marco Antonio; Pacheco Tobar, Esteban Alonso
In Azuay, agricultural organizations are highly vulnerable due to low productivity in mountainous areas. Surface irrigation exhibits efficiencies below 40%, while pressurized irrigation barely reaches 60%, significantly falling short of recommended standards. This underscores the necessity of implementing advanced irrigation systems to optimize water management and address agricultural challenges in rural areas. The study develops an experimental-demonstrative module for advanced irrigation, structured into three zones with a net irrigable area of 100 hectares and modules of 2000 m², subdivided into plots for crops such as maize, wheat, legumes, tubers, sugarcane, and citrus fruits. The evaluated methods include surface irrigation via furrows, sprinkler irrigation, and drip irrigation, selected based on soil type, topography, and water requirements. The design incorporates: i) Biophysical characterization relevant to the design of irrigation systems in mountain ecosystems; ii) Analysis of methods, procedures, and technologies for gravity and pressurized irrigation systems and their design; iii) Design of a prototype experimental module for the implementation of a technology transfer and scientific monitoring observatory. Subsequently, the module was dimensioned for the hydraulic system, and technical selection of components and equipment was conducted to ensure operational efficiency in each design.
Diseño de un sistema integral de riego tecnificado para la granja del Romeral de la Universidad de Cuenca
(Universidad de Cuenca, 2021-08-18) Lema Legarda, María Alejandra; Valla Poma, Shirley Johanna; Pacheco Tobar, Esteban Alonso
Universidad de Cuenca has experimental farms for training processes in the scientific fields of production and engineering. In order to promote agro-production and optimize water resources, it is necessary to improve the institutional infrastructure for irrigation, as well as the complementary infrastructure. In this context, for the “El Romeral” farm, it is proposed to carry out a reengineering study, which allows the Universidad de Cuenca, to have in the future, a technical and economic proposal for the implementation of new irrigation technologies, optimization of the water resource, and maximization of the production. For the study, it has been proposed: i) to characterize the project area and the biophysical aspects, through the analysis of available information, and the determination of the water needs for the project; ii) to analyze irrigation technology alternatives, identifying different operation and management scenarios for the conduction, distribution, and application of water for various methods; and, iii) to design a comprehensive technical proposal for the irrigation system, which includes main and complementary engineering works, and the economic needs of the project.. Through this study, an important contribution is made to the institutional processes for the sustainable development of infrastructure and experimentation centers, through which the training processes of the Faculty of Agricultural Sciences will be strengthened, as well as the interrelationships and academic collaboration with the Faculty of Engineering in the fields of irrigation engineering, irrigated agriculture, land management and agricultural drainage
Diseño del sistema de irrigación tecnificado para el Eco-campus Balzay de la Universidad de Cuenca
(Universidad de Cuenca, 2021-11-05) Arce Prieto, Alex Adrian; Pacheco Tobar, Esteban Alonso
The development of systems and technical solutions for green infrastructure that integrate: vegetation, soil management, and modernization of the water supply, is essential to reduce the negative effects of urbanization. In this sense, the present work focused on the design of a irrigation system for the green area of the Eco-campus Balzay (Universidad de Cuenca), contemplating management and operation components that respond to the planning of a modern ecological campus. For the development of the project, the area was characterized by identifying infrastructure requirements, physical conditions, water requirements for the development and maintenance of green areas, and alternatives for water provision. After having selected the irrigation methods and application technologies, the hydraulic and technical organization scheme for irrigation has been proposed, and the distribution system has been dimensioned by applying the model for flow hydraulics, EPANET. With this work, a comprehensive design for the irrigation system of the Eco-campus Balzay is proposed. The study considers the technical aspects of distribution-impulsion, as well as the management aspects, based on a technical organization scheme, by sectors and irrigation frequencies.
Diseño integral del sistema de drenaje longitudinal y trasversal para la carretera Nuñurco. Santa Rosa: tramo puente Collay Sta. Rosa de 3.7 km.
(2012) Castillo Moncayo, Gabriela Estefanía; Morales Palacios, Diana Alexandra; Pacheco Tobar, Esteban Alonso
Diseño, construcción e implementación de un sistema para la medición del resalto hidráulico producido en el canal hidrodinámico
(2017) Chumbi Guerrero, Diego Vinicio; Astudillo Salinas, Darwin Fabián; Pacheco Tobar, Esteban Alonso
In this work, an equipment was designed and implemented to measure the hydraulic jump generated in a hydrodynamic rectangular channel. The channel is used for the practices that are developed in the subject of hydraulics of the Civil Engineering career. This equipment measures the different heights in different sections of the channel, where the phenomenon of the hydraulic jump is generated. The measurement of the different heights is carried out by means of an ultrasonic distance sensor (the HC-SR04). To measure the horizontal displacement an incremental encoder is used, which is placed in the axis of the wheel of the equipment. Later, this information is sent wirelessly, via Bluetooth communication (with the help of the HC-06 module), to a computer that through a software (developed with MATLAB) will perform its respective processing to generate the graph that display the profile of the hydraulic jump generated. This project intends to change the way of developing hydraulic jump practice and give a technological alternative that encourages the interest in research and development of equipment, not only for this practice but also for many others that are carried out in conventional manner.
Estado del arte en manejo de sedimentos en cuencas andinas en el Ecuador, caso de estudio: cuenca del río Paute
(2017) Orbes Guartatanga, Jorge Eduardo; Peralta Quizhpi, Tania Gabriela; Pacheco Tobar, Esteban Alonso
The sustainable management of sediments is an untreated problem in Ecuador, however, it is of great importance to be directly related to water resources, to the use and use of them, and to environmental and ecological aspects. In the last decade, a large number of hydroelectric projects have been built in the country, which are beginning to feel the lack of a sediment management plan. These works represent an interruption in the transit of sediments from the upper parts to the lower parts of the river basins, as well as a problem and costs in the operation and maintenance of the existing projects. Punctual hydraulic solutions in the projects can contribute to optimize the management and the processes of sediment washing, however, in some cases around the world the loads received from sediments exceed the capacity of the hydraulic works, being a theme that evolves over time According to changes in land use within the river basin. This study contributes to the understanding and diffusion of the state of the art in studies and research on sediment management in Andean basins carried out in Ecuador. Taking the Paute basin as a case study, the study needs are identified in this issue and recommendations are set forth to contribute to initiatives to propose and implement sustainable management plans for sediments in Ecuador.
Estudio comparativo de los métodos de Martson y ATV para cálculo mecánico de tubos flexibles enterrados
(Universidad de Cuenca, 2025-09-23) Chimbo Vélez, Edgar Fernando; Guamán Coronel, Marcos Omar; Pacheco Tobar, Esteban Alonso
Diametral deformation in pipelines largely depends on whether the material is rigid or flexible. The Marston model, originally developed to simplify the mechanical load analysis for rigid pipes based on the Marston Spangler theory, allows its extension to flexible pipes through a modified equation. Alternatively, the ATV-DVWK-A 127 theory compiled in the UNE 53331 standard has been specifically developed for the mechanical analysis of flexible pipelines, accounting for both soil and live loads, as well as short- and long-term deformations occurring during installation. This study presents a comparative analysis of both theoretical approaches, along with the main regulatory considerations, through a case study involving the mechanical analysis of buried flexible pipelines under typical installation conditions. The comparison includes simulations carried out using the AseTUB software package, which follows the guidelines of the UNE 53331 standard. Results indicate that the Marston model is significantly more conservative than the normative approach, potentially leading to an overestimation of the loads acting on the pipe. In contrast, the ATV-DVWK-A 127 theory, as incorporated in the UNE 53331 standard, provides more realistic estimates for flexible pipes, as long as the input values are thoroughly applied in the equations defined by the standard. The present analysis aims to contribute to the improvement of calculation procedures and the practical applicability of the Marston-Spangler and ATV-DVWK-A 127 approaches.
Estudio comparativo de variantes de diseño de la estructura de evacuación de caudales de exceso de la presa Mocache mediante modelación física
(2017) Cárdenas Vásquez, Diana Cristina; Pacheco Tobar, Esteban Alonso
In the present titling work, physical hydraulic modeling has been used as a design technique to ensure optimal operation of the structure and to facilitate decision making. The structure for the evacuation of excess flows of the Mocache dam has been identified as a case study. The dam is part of the Megaproject "Plan de Aprovechamiento y Control del Agua, en la Provincia Los Ríos, PACALORI". Being a discharge structure constituted by two rapid ones, one of them in curved, fast form of flow that involves many disadvantages of erosion, undermining and sudden variations of drafts between the external and internal edges of the curve; for which it has been optimized its design, constructing a reduced scale physical model and implementing variants of design such as diagonal obstacles, concentric spans, cant transition and counterpendent (0.2% - 2%), and evaluating the results that these alternatives present for the maximum design flow rate. In addition, efficient variants are identified and combinations are made between them, resulting in even better results, such as adequate flow distribution and optimum velocities that do not exhibit undercutting phenomena. The study was concluded presenting the optimum alternative evaluated for four flow rates of design.
Estudio cualitativo en modelo geomorfológicos para una obra de derivación de caudales
(2011) Gárate Encalada, Johana Beatriz; Solís Bueno, Katty Maribel; Pacheco Tobar, Esteban Alonso