Ingeniero Civil Aeroespacial - UDEC
Doctor en Dinámica de Fluidos Geodésicos, UDEC
The interaction between local hydrodynamics conditions and salmon cages are important in disease transmission and in the transport of waste products generated by aquaculture. We propose a modeling methodology to assess the hydrodynamic effects of a salmon farm in a Patagonian channel. The method is based on the coupling between a Coastal and Regional Ocean COmmunity model (CROCO) and a high resolution Large Eddy Simulation (LES) model. A salmon farm located in the Estero Elefantes Channel (45°39′16.50″S73°35′59.40″W) was used as a study case. The physical coherence of the results was validated by comparison with field current velocities measured with an Acoustic Doppler Current Profiler (ADCP). The model predictions were capable of reproducing the tendencies of the variation although there were some differences in magnitude. The results showed that the hydrodynamics of the Estero Elefantes Channel is dominated by two circulation modes depending on the current direction in the adjacent Moraleda channel. Both circulation modes are characterized by a highly unstable shear flow composed by turbulent structures that interact with the salmon cages. Therefore it is not possible to select a local control volume with arbitrarily defined inlets, outlets and impermeable walls to evaluate hydrodynamic processes relevant to the salmon farms. The presence of the cages modifies the natural hydrodynamics of the channel, attenuating the intensity of the local velocity magnitude and generating recirculation and retention zones near them. However, their effect is not confined locally because the perturbations introduced by the presence of cages are propagated far from them. The transport of material discharged inside the cages was also analyzed. This information should prove useful both for producers and the aquaculture management authority. https://doi.org/10.1016/j.aquaculture.2018.05.003
Chile has begun to promote the use of biomass to replace a fraction of the energy produced from coal. However, the power plants are located in the world driest desert, the Atacama Desert, and far from the forest resources. Fortunately, a cactaceous species named Opuntia ficus-indica, has proven to be able to grow under climate desert conditions. In this study the behavior of Opuntia ficus-indica under co-firing conditions with coal, is evaluated and compared to that of Pinus radiata, in terms of heat transfer, ash deposits formation and pollutant emissions in a 150 kW fluidized bed pilot plant. The results revealed a variation of the temperature profile inside the reactor, as well as a relationship between the efficacy factor and the base-acid ratio. The heat transfer coefficients in the dense bed evidenced a decrease in the heat transfers mechanisms attributed to a variation of the mean particle diameter and a greater presence of fuel particles. Under coal-Pine co-firing conditions, an increase in NO formation and a decrease of PM and SO2 concentrations was observed. While co-firing coal with Opuntia showed an increase in the particulate matter and a reduction of NO and SO2 concentrations. https://doi.org/10.1016/j.energy.2017.10.053
Although roping in hydrocyclones is a problem that has been studied by many researchers, we do not yet have a theory that relates all the variables involved. Several experimental works with different approaches such as mechanical energy balance, work on hydrocyclones with water only and hydrocyclone air core measurements with different instruments in the laboratory and plant have attempted to explain the roping phenomenon. They have addressed design variables such as apex to vortex diameters and different cone angles as well as operating variables such as inlet solid concentration, particle size, pressure and overflow and underflow flow rates and concentrations in order to understand their effect on the roping condition. In this paper we intend to verify some of the conclusions of these studies and establish inlet pressure and particle diameter as the variables that, in combination, lead from spray to roping. We present a computational model using Computational Fluid Dynamics (CFD) to study a 75-mm laboratory hydrocyclone operating at a variable flow rate and with three different particle diameters. The Reynolds Stress Model and Eulerian multiphase model were used to model the turbulence and interaction of phases, respectively. The solid particles are described with the kinetic theory of granular flows (KTGF). Physical coherence and accuracy were compared with experimental data, where errors are within the expected range for an engineering prediction. The results indicate that transition from spray to roping generates an increase in the inlet flow pressure and/or particle diameter at a constant solid concentration in the feed flow. For 20-µm-diameter particles an increase results in a decrease in the discharge angle, although it always has a spray shape, for 34-µm diameters increasing the inlet pressure generates a semi-rope discharge and for 70-µm-diameter particles a small increase in the inlet pressure generates a roping condition. Transition to roping is characterized by a decrease in the air core diameter and discharge angle due to slow rotational velocity when particle diameter increases or higher accumulation of the solid fraction in the apex when inlet pressure increases. The passage from spray to roping occurs with a change in the frequency spectrum of the pressure oscillations in the walls of the hydrocyclone, with high amplitudes at low frequencies for spray discharge and noisy signals in all spectrums and damped low frequencies for roping. https://doi.org/10.1016/j.mineng.2018.04.008
Aerospace Science and Technology, en prensa
Aquaculture 430, 195-206, 2014
International Journal of Chemical Reactor Engineering, vol. 11, 2011, Article A2
Prof. Pablo Cornejo (Investigador Asociado)
Centro de Recursos Hídricos para la Agricultura y Minería (CRHIAM)
Numerical simulation of an upper ocean front using a Reynolds Stress Turbulence Model. Cornejo P.. 11th World Congress on Computational Mechanics. Barcelona, Spain. 2014
Modelo multifase con fase no-newtoniana para la simulación de la dinámica de relaves mineros. Montero J., Cornejo P.. XIII Jornadas de Mecánica Computacional, Universidad de Talca. Curicó, Chile. 2014
Modelación CFD de aire seco en régimen hipersónico. Pino C., Cornejo P.. XIII Jornadas de Mecánica Computacional, Universidad de Talca. Curicó, Chile. 2014
Submesoscale processes in upper ocean fronts: a numerical study using a Reynolds Stress Turbulence Model. Cornejo P.. Laboratorie de Physique des Océans. IFREMER-UBO. Brest, France. 2014
Simulación numérica de la formación de NOx en un quemador de gas natural. Romero P., Cornejo P., Farías O., Gallardo C.. XIII Jornadas de Mecánica Computacional, Universidad de Talca. Curicó, Chile. 2014
Estudio del efecto de la inclusión de biomasa en la combustión de carbón pulverizado. Pérez R., Cornejo P., Flores M., Gordon A., García X.. XIII Jornadas de Mecánica Computacional, Universidad de Talca. Curicó, Chile. 2014
Dinámica de fluidos geofísicos através de dinámica de fluidos computacional. Cornejo P.. ESSS conference and ANSYS users meeting. Santiago, Chile. 2014
Simulación numérica del efecto hidrodinámico de una jaula de cultivo de salmones en un ambiente idealizado. Cornejo P., Carrillo T., Sepúlveda H., Gutiérrez M., Olivares G.. XII Jornadas de Mecánica Computacional, Universidad de Santiago. Santiago, Chile. 2013
Evaluación de las características aerodinámicas de un cohete sonda en régimen de flujo compresible. Terán J.P., Cornejo P., Tinapp F.. XII Jornadas de Mecánica Computacional, Universidad de Santiago. Santiago, Chile. 2013
Evaluación de la estabilidad longitudinal de un trainer UAV mediante un modelo CFD-6DOF. Sandoval P., Cornejo P., Tinapp F.. XII Jornadas de Mecánica Computacional, Universidad de Santiago. Santiago, Chile. 2013
Biomass replacing in a pulverized coal utility boiler: predictions of performance and pollulant emissions using CFD tools. Cornejo P., Pérez R., Flores M., García X.. International conference on coal science and technology, The Pennsylvania State University. 2013
Simulación hidrodinámica del efecto de una jaula de cultivo bajo flujos idealizados. Cornejo P., Sepúlveda A., Gutierrez M. H.. IV Congreso Nacional de Acuicultura. 2012
Simulación numérica de jaulas de cultivo y su efecto sobre la hidrodinámica local. Cornejo P.. I-Mar, Universidad de Los Lagos. Puerto Montt, Chile. 2012
Hidrodinámica de jaulas de cultivo de salmones mediante dinámica de fluidos computacional (CFD). Cornejo P.. Seminarios de geofísica. Departamento de Geofísica, Universidad de Concepción. Concepción, Chile. 2012
Simulación numérica de la combustión de carbón pulverizado en un lecho arrastrado. P. Cornerjo, C. Rodríguez, O. Farías. VII Jornadas de Mecánica Computacional. Santiago. 2008
Tipo | Tema | Año semestre | Alumno | Enlace |
---|---|---|---|---|
Memoria | Evaluación del diseño aerodinámico preliminar de un auto híbrido y propuesta de mejoras.o (Pregrado) |
2017-06-06 | Alaff SaavedraMatias Eduardo | |
Memoria | Estudio de la aerodinámica de un auto solar biplaza mediante simulación numérica.o (Pregrado) |
2017-05-23 | Guerrero CerdaNicolas Matias | |
Memoria | Evaluación del desempeño de diseños preliminares de ultrafloculantes mediante simulación numérica.o (Pregrado) |
2017-03-29 | Del Río ReyesMarco Antonio | |
Memoria | Estudio del efecto de jaulas de cultivo de salmones sobre la hidrodinámica de un canal austral empleando un modelo CFD 3D.o (Pregrado) |
2017-01-18 | Herrera VenegasJulio Orlando | |
Memoria | Aproximación al comportamiento reológico de un fluido polidisperso mediante modelación CFD.o (Pregrado) |
2016-04-15 | Sandoval MaldonadoDarío Iván | |
Memoria | Simulación de combustión y formación de Nox en un quemador a gas.o (Pregrado) |
2016-03-16 | Valenzuela MoraIván Daniel | |
Memoria | Simulación numérica de un hidrociclón empleando un modelo CFD-DDPM.o (Pregrado) |
2016-03-02 | Pérez VillalobosDaniel Andrés | |
Memoria | Modelación hidrodinámica tridimensional de un canal austral.o (Pregrado) |
2015-05-06 | Herrera LobosRaul Alonso | |
Memoria | Modelo multifase con fase no-newtoniana para simulación de descarga de relaves mineros.o (Pregrado) |
2015-01-29 | Montero RafolsJosé Joaquín | |
Memoria | Predicción de la precipitación de nieve en faenas mineras de altura empleando el modelo WRF.o (Pregrado) |
2014-06-09 | MONTILLA SAKAANDRÉS | |
Memoria | Influencia de la deformación de mallas de cobre empleadas en acuicultura sobre el efecto hidrodinámico en una corriente empleando interacción fluido estructura.o (Pregrado) |
2014-04-02 | CARRILLO BELLOTOMÁS | |
Memoria | Simulación numérica de la formación de Nox en un quemador a gas.o (Pregrado) |
2014-03-24 | GALLARDO HARISMENDY CARLOS | |
Memoria | Optimización del difusor de una bomba centrífuga de flujo mixto.o (Pregrado) |
2014-01-31 | ARRIETA BONOMETTI JOSÉ | |
Memoria | Diseño e implementación de experiencias de laboratorio para el curso de propulsión.o (Pregrado) |
0000-00-00 | Quintana MezaDiego Andrés | |
Memoria | Simulación numérica directa de un caso de prueba tipo y comparación con datos experimentales disponible.o (Pregrado) |
0000-00-00 | Leal LópezIgnacio Antonio | |
Memoria | Influencia de la distribución granulométrica sobre el roping en hidrociclones.o (Pregrado) |
0000-00-00 | Daza OlaveJuan Gustavo | |
Memoria | Obtención de la matriz de generación de un generador undimotriz mediante simulación CFD-6DOF.o (Pregrado) |
0000-00-00 | Oñate CorreaCarla Lorena |