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11 resultados encontrados para: AUTOR: Alcérreca Huerta, Juan Carlos
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1.
Artículo
A 2D image-based approach for CFD validation of liquid mixing in a free-surface condition
Rodríguez Ocampo, P. E. (autor) ; Ring, M. (autor) ; Hernández Fontes, J. V. (autor) ; Alcérreca Huerta, Juan Carlos (autor) ; Mendoza Ramírez, Eduardo (autor) ; Gallegos Diez Barroso, Gabriel (autor) ; Silva, R. (autor) ;
Disponible en línea
Contenido en: Journal of Applied Fluid Mechanics Volume 13, número 5 (2020), p. 1487-1500 ISSN: 1735-3645
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Resumen en: Inglés |
Resumen en inglés

This study proposes an image-based approach to evaluate the validity of numerical results for cases where the setup can be assumed to be two-dimensional (2D) and mixing between liquids of different densities occurs under a free-surface condition. The proposed methodology is based on the estimation of the relative errors of the model through density matrices generated from images of the experimental and numerical results (i.e., post-processing snapshots of the density field). To demonstrate the use of the methodology, experimental tests and numerical simulations were performed for a double-dam-break problem with two miscible liquids. For the experiments, a high-speed camera was employed to capture details of the fluid interactions after the dam breaking. For the numerical simulations, an OpenFOAM® multiphase solver was employed to reproduce the benchmarking tests. Three turbulence approaches were tested: a zero-equation RANS model, a two-equation (k-epsilon) RANS model, and a Large-Eddy Simulation (LES) model. The experimental results compared favorably against the numerical results, with average drelative errors of ~17 and ~19% for the zero-equation and the two-equation turbulence models, respectively, and ~14% for the LES model. From the results obtained, it can be inferred that the two-equation (k-epsilon) model had limitations in reproducing the mixing between the liquid phases in terms of relative errors. The LES model reproduces the mixing between phases more accurately than zero and two-equation RANS models, which were seen to be more suitable for capturing the formation of large eddies in the initial phase of the experiment. The present methodology canbe improved and extended for different multiphase flow configurations.


2.
Artículo
CFD Simulations of Multiphase Flows: interaction of miscible liquids with different temperatures
Rodríguez Ocampo, Paola Elizabeth (autora) ; Ring, Michael (autor) ; Hernández Fontes, Jassiel Vladimir (autor) ; Alcérreca Huerta, Juan Carlos (autor) ; Mendoza, Edgar (autor) ; Silva, Rodolfo (autor) ;
Disponible en línea
Contenido en: Water Volumen 12, número 9, 2581 (2020), páginas 1-18 ISSN: 2073-4441
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Resumen en: Inglés |
Resumen en inglés

The incorporation of new equations to extend the applicability of open-source computational fluid dynamics (CFD) software according to the user’s needs must be complemented with code verification and validation with a representative case. This paper presents the development and validation of an OpenFOAM®-based solver suitable for simulating multiphase fluid flow considering three fluid phases with different densities and temperatures, i.e., two miscible liquids and air. A benchmark “dam-break” experiment was performed to validate the solver. Ten thermistors measured temperature variations in different locations of the experimental model and the temperature time series were compared against those of numerical probes in analogous locations. The accuracy of the temperature field assessment considered three different turbulence models: (a) zero-equation, (b) k-omega (Reynolds averaged simulation; RAS), and (c) large eddy simulation (LES). The simulations exhibit a maximum time-average relative and absolute errors of 9.3% and 3.1 K, respectively; thus, the validation tests proved to achieve an adequate performance of the numerical model. The solver developed can be applied in the modeling of thermal discharges into water bodies.


3.
- Artículo con arbitraje
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Dam implications on salt-water intrusion and land use within a tropical estuarine environment of the Gulf of Mexico
Alcérreca Huerta, Juan Carlos (autor) ; Callejas Jiménez, M. E. (autor) ; Carrillo Bibriezca, Laura Elena (autor) ; Castillo, M. M. (autor) ;
Contenido en: Science of the Total Environment Vol. 652 (February 2019), p. 1102-1112 ISSN: 1879-1026
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Resumen en: Inglés |
Resumen en inglés

Estuaries are highly productive ecosystems, defined by salt-freshwater exchanges that are significantly altered by changes upstream and in adjacent coastal areas. Tropical estuaries are characterized by the periodic advance and retreat of saline intrusion, depending on seasonality, episodic river flows and flooding events. Salt-water intrusion due to the estuarine dynamics might be affected by dam systems, which could modify the hydrological regime of the estuary in relation to other stressors, such as land use changes. For this purpose, field measurements of salinity, temperature, river-discharge and flow velocities were conducted over a year to analyze the current hydrological regime in the upper estuary of the Grijalva River in the southern Gulf of Mexico, part of the Biosphere Reserve “Pantanos de Centla” one of the most biodiverse areas in the world. Analysis of land use and vegetation cover was performed. Historical implications of the hydrological performance of the four-dam system (1957 to 2014) are presented, together with the upstream-induced changes (i.e. discharge and seasonal water volumes variations): before, between and after the full operation of the dam system.

A general loss of seasonality in the river discharge was identified (1974–1987), when critical mean annual water discharges were registered (Qmean from 263.56 to 126.49 m³/s). Chronological changes in the estuary and in the surrounding area due to the introduction of large extensions of cultivated grassland (~1020 km²), reduction in mangrove cover (~223 km²) and tular (~1340 km²) were noticed. These modifications mostly occurred before conservation strategies were implemented, such as the designation of the Biosphere Reserve (1992). This study contributes to a better understanding of the response of estuarine systems to anthropic perturbations and the development of long-term management plans that could take into account climate change and the increase of hydropower development.


4.
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Drag and inertia forces on a branched coral colony of Acropora palmata
Osorio Cano, Juan D. ; Osorio, Andrés F. (coaut.) ; Alcérreca Huerta, Juan Carlos (coaut.) ; Oumeraci, Hocine (coaut.) ;
Contenido en: Journal of Fluids and Structures Vol. 88 (July 2019), p. 31-47 ISSN: 0889-9746
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Resumen en: Inglés |
Resumen en inglés

Some branched corals are capable of surviving in wave/current exposed areas with moderate to high energy environments, where their branches, their geometry and the global and rigid structure of their colonies play an important role for wave damping due to bottom friction and wave energy dissipation due to turbulence. Constant frictional coefficients are commonly used within wave propagation models to consider reef roughness but without accounting for the type of coral species, its topological characteristics, form and distribution over the reef surface. In this sense, this study aims to improve the understanding of near-bed hydrodynamics in coral reefs by examining the drag and inertia coefficients of branched coral colonies of Acropora palmata. Laboratory tests were carried out considering steady and oscillatory flow conditions. In-line forces, flow velocities and water surface elevations over 3-D models of Acropora palmata were recorded for both a single coral colony and a group of corals. Additionally, the validated open source CFD (Computational Fluid Dynamics) toolbox OpenFOAM⃝R was used to simulate the hydrodynamic performance over the coral structures for a wide range of wave heights and periods. The results show that under steady flow conditions, the drag coefficient (CD) can be well represented as a function of the Reynolds number (Re) by means of a power law equation as CD = aReb+c. Also, under oscillatory flow conditions, it was found that the inertia force (FM) dominates over the drag component (FD), explaining more than 84% of the total force exerted on the coral structure.

Prediction formulas were developed and validated with the laboratory test to predict the resistance coefficients (drag and inertia) as function of Keulegan and Carpenter number (KC) for the CD (R² = 0.89) and CM (R² = 0.92). The CFD modeling showed to be an alternative for the modeling of the hydrodynamic forces exerted over complex coral shapes and to analyze the fluid–structure interaction around natural structures.


5.
Artículo
Resumen en: Inglés |
Resumen en inglés

Reefs are known to provide coastal protection and important ecosystem services for many coastlines around the world. Physicalprocesses such as wave damping, sediment transport and nearshore hydrodynamics are closely related to the coastal protectionservices provided by reefs. The steep-fronted bathymetries of reefs cause abrupt wave transformations and wave dampingalongshore, while reef roughness has an important contribution to coastal protection. Five Latin-American case studies arepresented to illustrate the coastal protection offered by reefs and their contribution to wave damping. The methodologies applied(e.g. numerical modelling, field measurements) and reef conditions (e.g. reef degradation scenarios and contribution of reefroughness) are listed. Considerable efforts have been made towards diagnosing, understanding and modelling the hydrodynamictransformations induced by reefs. Based on physical and field surveys, roughness and friction parameters were derived in order toimplement calibrated and validated numerical models. Discussion on the advantages and disadvantages of the different modelsapplied in the study cases is provided as well as on the needs of highlighting physical processes and the analysis of reefhydrodynamics for supporting appropriate ecosystem-based management.


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Resumen en: Inglés |
Resumen en inglés

Marine renewables represent a promising and innovative alternative source for satisfying the energy demands of growing populations while reducing the consumption of fossil fuels. Most technological advancements and energy yield assessments have focused on promoting the use of kinetic energy from tidal streams with flow velocities higher than 2.0 m s−1 . However, slower-moving flows from ocean currents are recently explored due to their nearly continuous and unidirectional seasonal flows. In this study, the potential of the Yucatan Current was analysed at nearshore sites over the insular shelf of Cozumel Island in the Mexican Caribbean. Field measurements were undertaken using a vessel-mounted Acoustic Doppler Current Profiler (ADCP) to analyse the spatial distribution of flow velocities, along with Conductivity-temperature-depth (CTD) profiles as well as data gathering of bathymetry and water elevations. Northward directed flow velocities were identified, with increasing velocities just before the end of the strait of the Cozumel Channel, where average velocities in the region of 0.88–1.04 m s−1 were recorded. An estimation of power delivery using horizontal axis turbines was undertaken with Blade Element Momentum theory. It was estimated that nearly 3.2 MW could be supplied to Cozumel Island, amounting to about 10% of its electricity consumption.


7.
- Artículo con arbitraje
Numerical and experimental assessment of the reflection coefficient of rubble mound breakwaters with an S shaped profile
Del Valle Morales, Jair ; Mendoza Baldwin, Edgar (coaut.) ; Alcérreca Huerta, Juan Carlos (coaut.) ; Silva Casarin, Rodolfo (coaut.) ;
Contenido en: Tecnología y Ciencias del Agua Vol. 10, no. 2 (April 2019), p. 128-152 ISSN: 0187-8336
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Resumen en: Español | Inglés |
Resumen en español

La reflexión debida a obras de abrigo es un fenómeno importante de cuantificar dado que, si no se controla, puede provocar problemas a la navegación, a la operación portuaria y, en casos extremos, a la estabilidad de la misma estructura. Dada la forma en que interactúan los taludes de los rompeolas y el oleaje, el coeficiente de reflexión es prácticamente único para cada tipología y forma de dique, por lo que su cálculo depende, además de las condiciones de clima marítimo, de las propiedades geométricas de la estructura, así como de su porosidad. En este trabajo se presenta una evaluación del coeficiente de reflexión para diques rompeolas de piezas sueltas con perfil en forma de “S” a partir de resultados obtenidos con el modelo OpenFOAM. Dicha información se comparó contra datos de laboratorio publicados en otras fuentes y contra algunas formulaciones disponibles en la literatura. Los resultados que ofrece el modelo numérico son muy parecidos a los reportados de manera experimental y, el modelo para el cálculo del coeficiente de reflexión obtenido mostró poca dispersión y buena precisión, en comparación con las formulaciones previas, por lo que puede emplearse en los rompeolas originales del estudio y también en otro tipo de estructuras.

Resumen en inglés

Quantification of the wave reflection from breakwaters is important due to the problems to navigation, port operation and structure stability it may induce. Given the complex interaction between waves and rough slopes, the reflection coefficient is properly unique for each dike type and shape, thus, its estimation depends not only on the wave climate conditions but on the geometry of the structure and its porosity. In this paper a numerical estimation of the reflection coefficient from “S” shaped breakwaters is given from the hydrodynamic results obtained via OpenFoam numerical tool. This information was compared to that published elsewhere and against previous available formulations. The numerical results map well within the ranges experimentally reported, while the best fit model proposed herein showed low dispersion and good precision against the previous formulations. This means that the simple model developed can be used to estimate the reflection coefficient from the originally studied structures and other several kind of structures as well.


8.
- Artículo con arbitraje
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CFD modelling of wave damping over a fringing reef in the Colombian Caribbean
Osorio Cano, Juan D. ; Alcérreca Huerta, Juan Carlos (coaut.) ; Osorio, Andrés F. (coaut.) ; Oumeraci, Hocine (coaut.) ;
Contenido en: Coral Reefs Vol. 37, no. 4 (December 2018), p. 1093–1108 ISSN: 0722-4028
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Resumen en: Inglés |
Resumen en inglés

The understanding of physical processes over submerged reefs represents an important ongoing research topic when considering wave energy dissipation and coastal protection that these environments provide. Detailed analyses are required to assess wave damping based on the contribution of reef roughness and wave breaking. For this purpose, the CFD (computational fluid dynamics) toolbox OpenFOAM® is applied to simulate the wave energy dissipation process over reefs with explicit accounting for the complexities of coral shape instead of commonly applied parameterized approaches for bottom roughness and wave breaking. Model validation was performed through comparison with field measurements over a reef profile of Tesoro Island in the Colombian Caribbean.


9.
Capítulo de libro
Conservación y agroturismo en Morelos: Hacienda San Miguel Treinta
Hernández Avilés, Dulce Aline ; Alcérreca Huerta, Juan Carlos (coaut.) ;
Contenido en: R50 restauración UNAM 50 años. Medio siglo de contribuciones de la maestría en restauración de monumentos Ciudad de México, México : Universidad Nacional Autónoma de México, Secretaría de Cultura, 2017 página 459-475 ISBN:978-1421423401
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10.
- Artículo con arbitraje
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Soil stability analysis for wave-induced momentary liquefaction beneath porous bonded revetments
Alcérreca Huerta, Juan Carlos ; Oumeraci, Hocine (coaut.) ;
Contenido en: Coastal Engineering Vol. 138 (August 2018), p. 22-35 ISSN: 0187-7674
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Resumen en: Inglés |
Resumen en inglés

The highly porous revetments made of Polyurethane Bonded Aggregates (PBA) are an ecologically friendly alternative to conventional revetments for protection against coastal erosion. No information has yet been reported for these structures on failures from field applications. However, a well-documented collapse of a PBA-revetment observed in large-scale tests (GWK tests) and a first stability analysis were reported by Oumeraci et al., 2010; 2012. Based on these results, a methodology is proposed for stability analysis of the embankment subsoil beneath PBA-revetments against momentary liquefaction, considering the results of the comprehensive parametric study (Alcérreca-Huerta, 2014) using a recently developed CFD-CSD (Computational Fluids Dynamics- Computational Solid Dynamics) model wavePoreGeoFoam (Alcérreca-Huerta and Oumeraci, 2016a; 2016b). It will be shown that the proposed stability analysis is able to reproduce the failure observed in the GWK tests, so that it can be applied for PBA-revetment under field conditions. In this paper, the failure observed in the GWK tests is first briefly reported, followed by a description of the numerical parametric study using the validated wavePoreGeoFoam model in order to extend the conditions tested in GWK. Then, the processes underlying soil liquefaction of PBA-revetments are outlined, showing that the excess pore pressure development in the sand core beneath PBA-revetments is crucial. The latter is therefore examined and a formula to predict excess pore pressures in terms of the wave conditions is developed. Moreover, a methodology for the stability analysis of the soil beneath the revetment against soil liquefaction is proposed and implemented to reproduce the failure observed in the GWK tests. Finally, the main results are summarized and implications for further research are drawn.