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For every nine tons of produced biodiesel, there is another ton of glycerol as a byproduct. Therefore, glycerol prices dropped significantly worldwide in recent years; the more significant biodiesel production is, the more glycerol exists as a byproduct. glycerol prices also impact the biodiesel manufacturing business, as it could be sold according to its refinement grade. The primary objective of this work was to evaluate the economic potential of the production of 1,2-propanediol derived from the biodiesel produced in Colombia. A plant to produce 1,2-propanediol via catalytic hydrogenation of glycerol in a trickle-bed reactor was designed. The plant comprised a reaction scheme where non-converted excess hydrogen was recycled, and the heat generated in the reactor was recovered. The reactor effluent was sent to a separation train where 98% m/m purity 1,2-propanediol was attained. Capital and operational costs were estimated from the process simulation. The net present value (NPV) and the modified internal return rate (MIRR) of the plant were used to assess the viability of the process. Their sensitivity to key input variables was evaluated to find the viability limits of the project. The economic potential of the 1,2-propanediol was calculated in USD 1.2/kg; for the base case, the NPV and the MIRR were USD 54.805 million and 22.56%, respectively, showing that, for moderate variations in products and raw material prices, the process is economically viable.
Juan B. Restrepo; Carlos D. Paternina-Arboleda; Antonio J. Bula. 1,2—Propanediol Production from Glycerol Derived from Biodiesel’s Production: Technical and Economic Study. Energies 2021, 14, 5081 .
AMA StyleJuan B. Restrepo, Carlos D. Paternina-Arboleda, Antonio J. Bula. 1,2—Propanediol Production from Glycerol Derived from Biodiesel’s Production: Technical and Economic Study. Energies. 2021; 14 (16):5081.
Chicago/Turabian StyleJuan B. Restrepo; Carlos D. Paternina-Arboleda; Antonio J. Bula. 2021. "1,2—Propanediol Production from Glycerol Derived from Biodiesel’s Production: Technical and Economic Study." Energies 14, no. 16: 5081.
Corncob is one of the most abundant agro-industrial wastes globally. It represents a bioenergy feedstock of 1500–5500 million tons per year. The shape and size of the corncob are suitable for gasification without pretreatment (size reduction, densification, or drying) in a downdraft gasifier. However, its volatile content (about 80% DAF) can generate high tar content, representing a challenge to adopt this technology. In the present work, an evaluation of the effect of air-steam mixture and calcium carbonate CaCO3 as a promoter of both reforming and gasification reaction was carried out using corn cob without grains as raw material in a 40 kW gasifier. An analysis of variance of four experimental treatments was used to determine the main statistical and interactive effects on the syngas composition, hydrogen yield (yH2), syngas lower heating value (LHVgas), and cold gas efficiency (CGE). Results reveal the highest gasification performance achieved hydrogen production yields of 310 Nml/g, an LHVgas value of 4.8 MJ/Nm3, and cold gas efficiency of 59.18% with steam and CaCO3. Statistical analysis indicated that CaCO3 and steam influence H2 production by increasing 15.8% and 10.8%, respectively, with a CaCO3/biomass ratio of 1% (w/w) and a Steam/biomass ratio of 11% (w/w). Main statistical effects were found for CGE increase of 5% with the addition of steam, 10% with CaCO3, and synergy of 10% using CaCO3 and steam simultaneously.
Rafael D. Gómez-Vásquez; Erika Arenas Castiblanco; Zulamita Zapata Benabithe; Antonio José Bula Silvera; Diego A. Camargo-Trillos. CaCO3 and air/steam effect on the gasification and biohydrogen performance of corn cob as received: Application in the Colombian Caribbean region. Biomass and Bioenergy 2021, 153, 106207 .
AMA StyleRafael D. Gómez-Vásquez, Erika Arenas Castiblanco, Zulamita Zapata Benabithe, Antonio José Bula Silvera, Diego A. Camargo-Trillos. CaCO3 and air/steam effect on the gasification and biohydrogen performance of corn cob as received: Application in the Colombian Caribbean region. Biomass and Bioenergy. 2021; 153 ():106207.
Chicago/Turabian StyleRafael D. Gómez-Vásquez; Erika Arenas Castiblanco; Zulamita Zapata Benabithe; Antonio José Bula Silvera; Diego A. Camargo-Trillos. 2021. "CaCO3 and air/steam effect on the gasification and biohydrogen performance of corn cob as received: Application in the Colombian Caribbean region." Biomass and Bioenergy 153, no. : 106207.
Alternative fuels for internal combustion engines (ICE) emerge as a promising solution for a more sustainable operation. This work assesses combustion and performance of the dual-fuel operation in the spark ignition (SI) engine that simultaneously integrates acetone–butanol–ethanol (ABE) and hydroxy (HHO) doping. The study evaluates four fuel blends that combine ABE 5, ABE 10, and an HHO volumetric flow rate of 0.4 LPM. The standalone gasoline operation served as the baseline for comparison. We constructed an experimental test bench to assess operation conditions, fuel mode, and emissions characteristics of a 3.5 kW-YAMAHA engine coupled to an alkaline electrolyzer. The study proposes thermodynamic and combustion models to evaluate the performance of the dual-fuel operation based on in-cylinder pressure, heat release rate, combustion temperature, fuel properties, energy distribution, and emissions levels. Results indicate that ABE in the fuel blends reduces in-cylinder pressure by 10–15% compared to the baseline fuel. In contrast, HHO boosted in-cylinder pressure up to 20%. The heat release rate and combustion temperature follow the same trend, corroborating that oxygen enrichment enhances gasoline combustion. The standalone ABE operation raises fuel consumption by around 10–25
Wilson Guillin-Estrada; Daniel Maestre-Cambronel; Antonio Bula-Silvera; Arturo Gonzalez-Quiroga; Jorge Duarte-Forero. Combustion and Performance Evaluation of a Spark Ignition Engine Operating with Acetone–Butanol–Ethanol and Hydroxy. Applied Sciences 2021, 11, 5282 .
AMA StyleWilson Guillin-Estrada, Daniel Maestre-Cambronel, Antonio Bula-Silvera, Arturo Gonzalez-Quiroga, Jorge Duarte-Forero. Combustion and Performance Evaluation of a Spark Ignition Engine Operating with Acetone–Butanol–Ethanol and Hydroxy. Applied Sciences. 2021; 11 (11):5282.
Chicago/Turabian StyleWilson Guillin-Estrada; Daniel Maestre-Cambronel; Antonio Bula-Silvera; Arturo Gonzalez-Quiroga; Jorge Duarte-Forero. 2021. "Combustion and Performance Evaluation of a Spark Ignition Engine Operating with Acetone–Butanol–Ethanol and Hydroxy." Applied Sciences 11, no. 11: 5282.
Propylene glycol, also known as 1,2 propanediol, is one of the most important chemicals in the industry. It is a water-soluble liquid, considered by the U.S. Food and Drug Administration as safe to manufacture consumer products, including foodstuffs, medicines, and cosmetics. This chemical has essential properties, such as solvent, moisturizer, or antifreeze, in addition to a low level of toxicity. This paper aims to present the selection, simulation, and dimensioning of a trickle bed reactor at a laboratory scale. The sizing was validated with other authors. Two predictive models have been considered for reactor modeling, intrinsic kinetics and coupled intrinsic kinetics, along with mass transfer equations and the wetting of the catalyst particles. The model was implemented using Aspen Custom Modeler® (20 Crosby Dr. Bedford, MA 01730, EE. UU.) to study the reactor behavior in terms of conversion. The results show the profiles of different variables throughout the reactor and present higher glycerol conversion when mass transfer is added to the model.
Juan Restrepo; Johnnys Bustillo; Antonio Bula; Carlos Paternina. Selection, Sizing, and Modeling of a Trickle Bed Reactor to Produce 1,2 Propanediol from Biodiesel Glycerol Residue. Processes 2021, 9, 479 .
AMA StyleJuan Restrepo, Johnnys Bustillo, Antonio Bula, Carlos Paternina. Selection, Sizing, and Modeling of a Trickle Bed Reactor to Produce 1,2 Propanediol from Biodiesel Glycerol Residue. Processes. 2021; 9 (3):479.
Chicago/Turabian StyleJuan Restrepo; Johnnys Bustillo; Antonio Bula; Carlos Paternina. 2021. "Selection, Sizing, and Modeling of a Trickle Bed Reactor to Produce 1,2 Propanediol from Biodiesel Glycerol Residue." Processes 9, no. 3: 479.
A mathematical model studying the dynamic of planing hulls with six degrees of freedom is developed. The turning circle as well as the zigzag maneuvers are simulated with this model. The results are compared with CFD (computational fluid dynamics) simulations and experimental results reported by others authors with good agreement. A numerical experiment design was performed to evaluate the maneuverability in prismatic hulls in planing regime, the response variables of the experiment are the tactical diameter and the advance in the turning circle test. The experiment factors are: the displacement, the test velocity, the deadrise angle of the hull, the horizontal position of the gravity center, the vertical position of the gravity center, and the rudder angle. The experiment results were used to generate a response surface and a regression model that allows evaluate the maneuverability as a function of the main design variables. The development of the model identified different conditions where the boat presents dynamic instability in the vertical and transversal planes.
Roberto Algarín; Antonio Bula. A numeric study of the maneuverability of planing hulls with six degrees of freedom. Ocean Engineering 2020, 221, 108514 .
AMA StyleRoberto Algarín, Antonio Bula. A numeric study of the maneuverability of planing hulls with six degrees of freedom. Ocean Engineering. 2020; 221 ():108514.
Chicago/Turabian StyleRoberto Algarín; Antonio Bula. 2020. "A numeric study of the maneuverability of planing hulls with six degrees of freedom." Ocean Engineering 221, no. : 108514.
Session 2520 Development of a Tutorial Software to Serve as a Teaching Aid for Power and Refrigeration Cycles Muhammad M. Rahman and Antonio J. Bula Department of Mechanical Engineering University of South Florida 4202 E. Fowler Avenue, ENB 118 Tampa, Florida 33620-5350 ABSTRACT The paper presents the development and application of a computer based tutorial software to aid instruction and improve problem solving skills in undergraduate “Thermal Systems and Economics” course offered by the Department of Mechanical Engineering. This course is a required design course in the Mechanical Engineering curriculum and an approved technical elective in the Chemical Engineering curriculum. It is offered during both fall and spring semesters with a class size of about 40 students. The expert tutor serves as a concise data base for key concepts learned in the course, and houses property tables and basic equations to interactively solve problems. The benefits of using this computer based instructional aid include: enhanced use of multimedia course materials, more creative thinking exercises for students, reduced time to master new concepts, and coverage of more materials in the course. The application of computer technology to facilitate interactive learning greatly enhances the instruction process. The concept of an expert tutor can be extended virtually to any engineering or science course at the undergraduate level. INTRODUCTION Thermodynamics is a core course in engineering curriculum throughout the nation. All engineering students are required to take the Basic Thermodynamics (usually known as Thermodynamics I) irrespective of their major discipline. Students majoring in Mechanical Engineering are required to take the Applied Thermodynamics (usually known as Thermodynamics II or Thermal Systems) where they apply the principles of thermodynamics to design power plants, reciprocating internal combustion engines, gas turbines and aircraft engines, and refrigeration and air-conditioning machinery. The design exercises usually require repeated calculations using properties of the working fluid (or fluids). The fluid properties are usually provided in a tabulated form and listed as a function of temperature and pressure. Equations correlating the properties are available only for simple substances such as an ideal gas. Calculation of fluid properties for different thermodynamic states usually sum up to a major portion of time needed to solve any problem. Hand calculations are tedious because of interpolation of tabulated data. Therefore, there is a great need for a computer-based property data bank where once a thermodynamic state has been defined by two independent properties, all remaining properties of the state can be readily obtained. In addition, if a student can set up a problem interactively in the computer and can execute the solution steps in an interactive fashion without tedious hand calculations, that definitely increases productivity on the part of the student as well as the instructor.
Muhammad M. Rahman; Antonio Bula. Development Of A Tutorial Software To Serve As A Teaching Aid For Power And Refrigeration Cycles. 1998 Annual Conference Proceedings 2020, 3.206.1 -3.206.8.
AMA StyleMuhammad M. Rahman, Antonio Bula. Development Of A Tutorial Software To Serve As A Teaching Aid For Power And Refrigeration Cycles. 1998 Annual Conference Proceedings. 2020; ():3.206.1-3.206.8.
Chicago/Turabian StyleMuhammad M. Rahman; Antonio Bula. 2020. "Development Of A Tutorial Software To Serve As A Teaching Aid For Power And Refrigeration Cycles." 1998 Annual Conference Proceedings , no. : 3.206.1-3.206.8.
The Gordon-Ng models are tools that have been used to estimate and evaluate the performance of various types of chillers for several years. A 550 TR centrifugal chiller plant facility was available to collect data from July and September 2018. The authors propose rearranging variables of the traditional (GNU) model based on average electric consumption and through a thermodynamic analysis comparable to the original model. Furthermore, assumptions are validated. Then, by estimation of the parameters of the new model using least square fitting with field training data and comparing to the GNU model and Braun model (based on consumption), it was shown that the proposed model provides a better prediction in order to evaluate consumption of a centrifugal chiller in regular operation, by improving the coefficient of variation (CV), CV = 3.24% and R2 = 92.52% for a filtered sub-data. Through an algorithm built from steady-state cycle analysis, physical parameters (Sgen, Qleak,eq, R) were estimated to compare with the same parameters obtained by regression to check the influence of the interception term in the model. It was found that without an interception term, the estimated parameters achieve relative errors (ER) below 20%. Additional comparison between external and internal power prediction is shown, with CV = 3.57 % and mean relative error (MRE) of 2.7%, achieving better accuracy than GNU and Braun model.
Blanca Foliaco; Antonio Bula; Peter Coombes. Improving the Gordon-Ng Model and Analyzing Thermodynamic Parameters to Evaluate Performance in a Water-Cooled Centrifugal Chiller. Energies 2020, 13, 2135 .
AMA StyleBlanca Foliaco, Antonio Bula, Peter Coombes. Improving the Gordon-Ng Model and Analyzing Thermodynamic Parameters to Evaluate Performance in a Water-Cooled Centrifugal Chiller. Energies. 2020; 13 (9):2135.
Chicago/Turabian StyleBlanca Foliaco; Antonio Bula; Peter Coombes. 2020. "Improving the Gordon-Ng Model and Analyzing Thermodynamic Parameters to Evaluate Performance in a Water-Cooled Centrifugal Chiller." Energies 13, no. 9: 2135.
Planing boat dynamics are a complex phenomenon and the maneuver forces acting on these kind of hulls are difficult to predict. In the current work, a mathematical model of a two-dimensional impact with three degrees of freedom (3DOF) is developed. The model was used to study wedge sections with knuckles, the vertical, horizontal, and rotational motion are considered. Pressure distribution, forces, and motion during the impact, considering both free fall and forced motion, are evaluated. The commercial CFD (Computational flow dynamics) software Star-CCM+ V9.06 was used to validate the formulation. Simulations with one, two, and three degrees of freedom were carried out, and the results were compared with CFD simulations, experimental data, and numerical solutions by others authors. The results show a good agreement with the authors. The model is extended to three dimensions applying slender body theory, and the forces in the hull are computed. The formulation allows evaluating the seakeeping with cross flow, dynamic stability, and manoeuvrability of planing boats with variable sections over the length.
Roberto Algarín; Antonio Bula. Two-Dimensional Impact Modelling with Three Degrees of Freedom and Its Application in the Dynamics of Planing Hulls. Applied Sciences 2020, 10, 1072 .
AMA StyleRoberto Algarín, Antonio Bula. Two-Dimensional Impact Modelling with Three Degrees of Freedom and Its Application in the Dynamics of Planing Hulls. Applied Sciences. 2020; 10 (3):1072.
Chicago/Turabian StyleRoberto Algarín; Antonio Bula. 2020. "Two-Dimensional Impact Modelling with Three Degrees of Freedom and Its Application in the Dynamics of Planing Hulls." Applied Sciences 10, no. 3: 1072.
Se evaluó el efecto de mezclas (%w) de tusa de residuos de maíz (TM) y cascara de desmote de algodón (CA) sobre el poder calorífico (LHV) y el rendimiento de conversión del carbono. Se realizó un análisis de varianza para comprobar el efecto aislado de la mezcla TM-CA, variando el porcentaje de mezcla entre 100-0, 90-10, 70-30 y 60-40, cambiando el flujo de succión (FS) para mantener el ER entre 0.27-0.35 y temperatura media de 980°C. Se evidenció un efecto sinérgico en el poder calorífico del gas (LHV) para una mezcla TM-CA 90-10, alcanzando un aumento máximo de 22.11% del LHV en comparación a la media global y 26.31% con respecto a la mezcla 100-0 con LHV de 3.8MJ/Nm3. Así mismo se alcanzó una mejora en la conversión de carbono de 20.7%. El trabajo muestra que cuando se emplean mezclas de biomasa, se pueden presentar sinergias, debido a complejas interacciones durante la conversión, y es importante desarrollar herramientas de análisis experimentales que permitan identificarlas.
Rafael D. Gómez; Diego A Camargo; Cristian C Soto; Antonio J. Bula. Evaluación Sinérgica de la Gasificación de Biomasa Residual en Mezclas de Maíz y Algodón. Información tecnológica 2019, 30, 11 -20.
AMA StyleRafael D. Gómez, Diego A Camargo, Cristian C Soto, Antonio J. Bula. Evaluación Sinérgica de la Gasificación de Biomasa Residual en Mezclas de Maíz y Algodón. Información tecnológica. 2019; 30 (6):11-20.
Chicago/Turabian StyleRafael D. Gómez; Diego A Camargo; Cristian C Soto; Antonio J. Bula. 2019. "Evaluación Sinérgica de la Gasificación de Biomasa Residual en Mezclas de Maíz y Algodón." Información tecnológica 30, no. 6: 11-20.
Palm kernel meal (PKM) is one of the main byproducts of the oil palm industry. PKM can be obtained as the result of solvent or mechanical extraction of palm kernel oil; in both cases, meal has a remaining oil content that could be recovered. In this work, PKM coming from a mechanical pressing extraction system with an initial oil content between 7 to 8% (wt.) was treated with subcritical water in a batch stirred reactor. To find the proper operational conditions, a three-step experimental process was performed. Extraction temperature, reaction time, particle size and alkaline catalyst usage were selected as process factors. After subcritical extraction, the system was cooled down and depressurized; then oil phase was separated by centrifugation. After extraction, meal was oven-dried at 80 °C. A maximum recovery of 0.034 kg-oil/kg-meal was obtained at 423 K, 720 s and particles smaller than 0.001 m. The experimental procedure showed consistent extraction yields of 40% without modifying the quality of the obtained oil.
Johnnys Bustillo Maury; Andrés Aldana Rico; Cindy Lorena García Pinto; Ingrid Hernández Medina; Juan Urueta Urueta; Jerry W. King; Antonio Bula Silvera. Oil Recovery from Palm Kernel Meal Using Subcritical Water Extraction in a Stirred Tank Reactor. Processes 2019, 7, 797 .
AMA StyleJohnnys Bustillo Maury, Andrés Aldana Rico, Cindy Lorena García Pinto, Ingrid Hernández Medina, Juan Urueta Urueta, Jerry W. King, Antonio Bula Silvera. Oil Recovery from Palm Kernel Meal Using Subcritical Water Extraction in a Stirred Tank Reactor. Processes. 2019; 7 (11):797.
Chicago/Turabian StyleJohnnys Bustillo Maury; Andrés Aldana Rico; Cindy Lorena García Pinto; Ingrid Hernández Medina; Juan Urueta Urueta; Jerry W. King; Antonio Bula Silvera. 2019. "Oil Recovery from Palm Kernel Meal Using Subcritical Water Extraction in a Stirred Tank Reactor." Processes 7, no. 11: 797.
This work develops a methodology based on real chemical plant data collected from a Nitrogen-Phosphorus-Potassium fertilizer (NPK) cooling rotary drum. By blending thermodynamic variables given by global energy and mass balances with computational fluid dynamics-discrete element method (CFD-DEM) modeling and simulation, the methodology provides an initial approximation to the understanding of heat transfer inside industry rotary coolers. The NPK cooling process was modeled in CFD software Simcenter STAR − CCM + 13.06.011 using a Eulerian–Lagrangian scheme through a coupled CFD-DEM method using one-way coupling. The average temperature of the NPK particles was obtained as well as the average mass flow of the particles dropping as the drum was rotating. The analysis was performed for two-particle diameters (8 and 20 mm) during 17.5 s. The average heat transfer coefficient between the fluid and the NPK particles during the simulated time was obtained. A thermodynamic analysis was carried out using instantaneous energy and mass balances. Prandtl, Nusselt, and Reynolds numbers were obtained for each simulated time step. Finally, through a non-linear regression using the Marquardt method, a correlation between Prandtl, Nusselt, and Reynolds number was developed that allowed analyzing the rotating drum. Results showed that the proposed methodology could serve as a useful tool during the design and analysis of any given rotary cooler, allowing calculation of the heat transfer coefficient and obtaining the process variables that could expand the machine operational capabilities due to the knowledge of the Nusselt number as a function of the drum working parameters.
Francisco Burgos-Florez; Antonio Bula; John Marquez; Alberto Ferrer; Marco Sanjuan. CFD-DEM Modeling and Simulation Coupled to a Global Thermodynamic Analysis Methodology for Evaluating Energy Performance: Biofertilizer Industry. Processes 2019, 7, 673 .
AMA StyleFrancisco Burgos-Florez, Antonio Bula, John Marquez, Alberto Ferrer, Marco Sanjuan. CFD-DEM Modeling and Simulation Coupled to a Global Thermodynamic Analysis Methodology for Evaluating Energy Performance: Biofertilizer Industry. Processes. 2019; 7 (10):673.
Chicago/Turabian StyleFrancisco Burgos-Florez; Antonio Bula; John Marquez; Alberto Ferrer; Marco Sanjuan. 2019. "CFD-DEM Modeling and Simulation Coupled to a Global Thermodynamic Analysis Methodology for Evaluating Energy Performance: Biofertilizer Industry." Processes 7, no. 10: 673.
This paper presents a theoretical investigation of a new configuration of the combined power and cooling cycle known as the Goswami cycle. The new configuration consists of two turbines operating at two different working pressures with a low-heat source temperature, below 150 °C. A comprehensive analysis was conducted to determine the effect of key operation parameters such as ammonia mass fraction at the absorber outlet and boiler-rectifier, on the power output, cooling capacity, effective first efficiency, and effective exergy efficiency, while the performance of the dual-pressure configuration was compared with the original single pressure cycle. In addition, a Pareto optimization with a genetic algorithm was conducted to obtain the best power and cooling output combinations to maximize effective first law efficiency. Results showed that the new dual-pressure configuration generated more power than the single pressure cycle, by producing up to 327.8 kW, while the single pressure cycle produced up to 110.8 kW at a 150 °C boiler temperature. However, the results also showed that it reduced the cooling output as there was less mass flow rate in the refrigeration unit. Optimization results showed that optimum effective first law efficiency ranged between 9.1% and 13.7%. The maximum effective first law efficiency at the lowest net power (32 kW) and cooling (0.38 kW) outputs was also shown. On the other hand, it presented 13.6% effective first law efficiency when the net power output was 100 kW and the cooling capacity was 0.38 kW.
Gustavo Guzmán; Lucía De Los Reyes; Eliana Noriega; Hermes Ramírez; Antonio Bula; Armando Fontalvo. Thermal Optimization of a Dual Pressure Goswami Cycle for Low Grade Thermal Sources. Entropy 2019, 21, 711 .
AMA StyleGustavo Guzmán, Lucía De Los Reyes, Eliana Noriega, Hermes Ramírez, Antonio Bula, Armando Fontalvo. Thermal Optimization of a Dual Pressure Goswami Cycle for Low Grade Thermal Sources. Entropy. 2019; 21 (7):711.
Chicago/Turabian StyleGustavo Guzmán; Lucía De Los Reyes; Eliana Noriega; Hermes Ramírez; Antonio Bula; Armando Fontalvo. 2019. "Thermal Optimization of a Dual Pressure Goswami Cycle for Low Grade Thermal Sources." Entropy 21, no. 7: 711.
A new methodology for predicting the real instantaneous in-cylinder volume in the combustion chamber of a reciprocating internal combustion engine is implemented. The mathematical model developed as part of this methodology, takes into consideration the deformations due to pressure and inertial forces, via a deformation constant adjusted through ANSYS®, using a high-precision CAD model of a SOKAN SK-MDF300 engine. The deformation constant was obtained from the CAD model using the computational tool ANSYS® and the pressure data was obtained from the engine running at three regimes: 1500, 2500, and 3500 rpm. The results were compared with previous models reported in the literature, showing that the deformation constant obtained has a smaller variation among cycles, which leads to a more precise value of the mechanical deformations. Furthermore, to have a more accurate model of the instantaneous volume variation, a factor taking into consideration the lubricant film behavior is introduced to calculate volumetric variation due to geometrical clearances. The influence of the introduced volumetric variation was evaluated through a process of combustion diagnosis, evidencing the improvement in the predictive capacity of thermodynamic modeling and, therefore, the correct prediction of heat release rate.
Franklin Consuegra; Antonio Bula; Wilson Guillín; Jonathan Sánchez; Jorge Duarte Forero. Instantaneous in-Cylinder Volume Considering Deformation and Clearance due to Lubricating Film in Reciprocating Internal Combustion Engines. Energies 2019, 12, 1437 .
AMA StyleFranklin Consuegra, Antonio Bula, Wilson Guillín, Jonathan Sánchez, Jorge Duarte Forero. Instantaneous in-Cylinder Volume Considering Deformation and Clearance due to Lubricating Film in Reciprocating Internal Combustion Engines. Energies. 2019; 12 (8):1437.
Chicago/Turabian StyleFranklin Consuegra; Antonio Bula; Wilson Guillín; Jonathan Sánchez; Jorge Duarte Forero. 2019. "Instantaneous in-Cylinder Volume Considering Deformation and Clearance due to Lubricating Film in Reciprocating Internal Combustion Engines." Energies 12, no. 8: 1437.
Se determina mediante el uso de herramientas computacionales el comportamiento de la hidrólisis del aceite de soja con agua subcrítica. Empleando la cinética de reacción de segundo orden propuesta en la literatura, se realiza una simulación fluido dinámica empleando el programa COMSOL MULTIPHYSICS. Se utiliza un enfoque 2D en un plano horizontal que representa la sección transversal de un reactor agitado. Se consideraron los efectos turbulentos y se seleccionaron los modelos TRANS y κ-ε para las simulaciones, que se desarrollaron a tres niveles de calentamiento (523K, 548K y 573K). Los resultados obtenidos a 548K fueron consecuentes con los datos experimentales referenciados, presentando un error aproximado de 4% con lo reportado.
Andrés F. Aldana; Johnnys A. Bustillo; Juan C. Urueta; Antonio J. Bula. Dinámica de Fluidos Computacional de la Hidrólisis de Aceite de Soja Bajo Condiciones de Agua Subcrítica en un Reactor de Tanque Agitado. Información tecnológica 2018, 29, 47 -60.
AMA StyleAndrés F. Aldana, Johnnys A. Bustillo, Juan C. Urueta, Antonio J. Bula. Dinámica de Fluidos Computacional de la Hidrólisis de Aceite de Soja Bajo Condiciones de Agua Subcrítica en un Reactor de Tanque Agitado. Información tecnológica. 2018; 29 (5):47-60.
Chicago/Turabian StyleAndrés F. Aldana; Johnnys A. Bustillo; Juan C. Urueta; Antonio J. Bula. 2018. "Dinámica de Fluidos Computacional de la Hidrólisis de Aceite de Soja Bajo Condiciones de Agua Subcrítica en un Reactor de Tanque Agitado." Información tecnológica 29, no. 5: 47-60.
Oscar Pupo; Samira Garcia; Leonardo Di Mare; Sandra Gomez; Antonio Bula. Optimization of Chaetoceros gracilis Microalgae Production for Fish Feeding Using an Airlift Photobioreactor. Advance Journal of Food Science and Technology 2018, 15, 83 -90.
AMA StyleOscar Pupo, Samira Garcia, Leonardo Di Mare, Sandra Gomez, Antonio Bula. Optimization of Chaetoceros gracilis Microalgae Production for Fish Feeding Using an Airlift Photobioreactor. Advance Journal of Food Science and Technology. 2018; 15 (SPL):83-90.
Chicago/Turabian StyleOscar Pupo; Samira Garcia; Leonardo Di Mare; Sandra Gomez; Antonio Bula. 2018. "Optimization of Chaetoceros gracilis Microalgae Production for Fish Feeding Using an Airlift Photobioreactor." Advance Journal of Food Science and Technology 15, no. SPL: 83-90.
The Goswami cycle is a cycle that combines an ammonia–water vapor absorption cycle and a Rankine cycle for cooling and mechanical power purposes by using thermal heat sources such as solar energy or geothermal steam. In this paper, a theoretical investigation was conducted to determine the performance outputs of the cycle, namely, net mechanical power, cooling, effective first law efficiency and exergy efficiency, for a boiler and an absorber temperature of 85 °C and 35 °C, respectively, and different boiler pressures and ammonia-water concentrations. In addition, an experimental investigation was carried out to verify the predicted trends of theoretical analysis and evaluate the performance of a modified scroll expander. The theoretical analysis showed that maximum effective first law and exergy efficiencies were 7.2% and 45%, respectively. The experimental tests showed that the scroll expander reached a 30–40% of efficiency when boiler temperature was 85 °C and rectifier temperature was 55 °C. Finally, it was obtained that superheated inlet conditions improved the efficiency of the modified expander.
Gokmen Demirkaya; Ricardo Vasquez Padilla; Armando Fontalvo; Antonio Bula; D. Yogi Goswami. Experimental and Theoretical Analysis of the Goswami Cycle Operating at Low Temperature Heat Sources. Journal of Energy Resources Technology 2018, 140, 072005 .
AMA StyleGokmen Demirkaya, Ricardo Vasquez Padilla, Armando Fontalvo, Antonio Bula, D. Yogi Goswami. Experimental and Theoretical Analysis of the Goswami Cycle Operating at Low Temperature Heat Sources. Journal of Energy Resources Technology. 2018; 140 (7):072005.
Chicago/Turabian StyleGokmen Demirkaya; Ricardo Vasquez Padilla; Armando Fontalvo; Antonio Bula; D. Yogi Goswami. 2018. "Experimental and Theoretical Analysis of the Goswami Cycle Operating at Low Temperature Heat Sources." Journal of Energy Resources Technology 140, no. 7: 072005.
Paddy drying is one of the main operations on the rice milling industry and it has a wide impact in terms of kernel quality, infestation reduction and costs of operation. That is why process control is one of the main fields to ensure a successful operation. This paper presents the development of an industrial scale drying rate prediction model. The model includes on his structure mass balance equations, drying rate and bulk density equation and an experimental expression that estimates the rate of change in moisture as a function of the dry basis kernel water fraction, Sherwood number, mass transfer Biot number and a proposed non-dimensional temperature -Nt-. The importance of including -Nt- parameter is based on the thermal gradients between the drying air, internal kernel water and the installation environmental conditions. These factors create a distinctive characteristic from other drying rate prediction models because they associate the process with environmental conditions of the location where drying operation takes place.
Andrés Aldana; Diego Guillén; Antonio Bula; Marco Sanjuán. Development of a Predictive Model for the Mass Transfer on the Paddy Rice (Oryza Sativa) Tower Drying Operation at Industrial Scale. Volume 4A: Dynamics, Vibration, and Control 2017, 1 .
AMA StyleAndrés Aldana, Diego Guillén, Antonio Bula, Marco Sanjuán. Development of a Predictive Model for the Mass Transfer on the Paddy Rice (Oryza Sativa) Tower Drying Operation at Industrial Scale. Volume 4A: Dynamics, Vibration, and Control. 2017; ():1.
Chicago/Turabian StyleAndrés Aldana; Diego Guillén; Antonio Bula; Marco Sanjuán. 2017. "Development of a Predictive Model for the Mass Transfer on the Paddy Rice (Oryza Sativa) Tower Drying Operation at Industrial Scale." Volume 4A: Dynamics, Vibration, and Control , no. : 1.
Low-grade heat sources such as solar thermal, geothermal, exhaust gases and industrial waste heat are suitable alternatives for power generation which can be exploited by means of small-scale Organic Rankine Cycle (ORC). This paper combines thermodynamic optimization and economic analysis to assess the performance of single and dual pressure ORC operating with different organic fluids and targeting small-scale applications. Maximum power output is lower than 45 KW while the temperature of the heat source varies in the range 100–200 °C. The studied working fluids, namely R1234yf, R1234ze(E) and R1234ze(Z), are selected based on environmental, safety and thermal performance criteria. Levelized Cost of Electricity (LCOE) and Specific Investment Cost (SIC) for two operation conditions are presented: maximum power output and maximum thermal efficiency. Results showed that R1234ze(Z) achieves the highest net power output (up to 44 kW) when net power output is optimized. Regenerative ORC achieves the highest performance when thermal efficiency is optimized (up to 18%). Simple ORC is the most cost-effective among the studied cycle configurations, requiring a selling price of energy of 0.3 USD/kWh to obtain a payback period of 8 years. According to SIC results, the working fluid R1234ze(Z) exhibits great potential for simple ORC when compared to conventional R245fa.
Armando Fontalvo; Jose Solano; Cristian Pedraza; Antonio Bula; Arturo Gonzalez Quiroga; Ricardo Vasquez Padilla. Energy, Exergy and Economic Evaluation Comparison of Small-Scale Single and Dual Pressure Organic Rankine Cycles Integrated with Low-Grade Heat Sources. Entropy 2017, 19, 476 .
AMA StyleArmando Fontalvo, Jose Solano, Cristian Pedraza, Antonio Bula, Arturo Gonzalez Quiroga, Ricardo Vasquez Padilla. Energy, Exergy and Economic Evaluation Comparison of Small-Scale Single and Dual Pressure Organic Rankine Cycles Integrated with Low-Grade Heat Sources. Entropy. 2017; 19 (10):476.
Chicago/Turabian StyleArmando Fontalvo; Jose Solano; Cristian Pedraza; Antonio Bula; Arturo Gonzalez Quiroga; Ricardo Vasquez Padilla. 2017. "Energy, Exergy and Economic Evaluation Comparison of Small-Scale Single and Dual Pressure Organic Rankine Cycles Integrated with Low-Grade Heat Sources." Entropy 19, no. 10: 476.
An experimental research has been conducted for evaluating heat transfer in a modified configuration of a submerged radial jet, so it was possible to extract the fluid directly under the nozzle, looking for an improvement in the heat transfer rate. The experiments were conducted for the following ranges of the phenomenon governing parameters: 16 mm nozzle diameter, nozzle to plate distance ranging from 10 mm to 20 mm, Reynolds number ranging between 10,000 and 20,000, and heat density of 10.2 – 13.6 kW/m2. The heat transfer coefficient as well as Nusselt number for the different conditions under study were estimated using the temperature distribution obtained from a data acquisition device and appropriated post-processing. The use of fluid extraction through induced draft generated a significant increase in heat transfer in the area under the nozzle, obtaining values ranging from 290 up to 1500 W/m2.°C.
Argemiro Palencia Díaz; Universidad Autónoma Del Caribe; Cesar Barraza-Botet; Antonio José Bula-Silvera; University of Michigan; Universidad Del Norte. Experimental study of flat plate cooling using draft induced by a submerged radial jet. Revista Facultad de Ingeniería Universidad de Antioquia 2017, 57 -64.
AMA StyleArgemiro Palencia Díaz, Universidad Autónoma Del Caribe, Cesar Barraza-Botet, Antonio José Bula-Silvera, University of Michigan, Universidad Del Norte. Experimental study of flat plate cooling using draft induced by a submerged radial jet. Revista Facultad de Ingeniería Universidad de Antioquia. 2017; (83):57-64.
Chicago/Turabian StyleArgemiro Palencia Díaz; Universidad Autónoma Del Caribe; Cesar Barraza-Botet; Antonio José Bula-Silvera; University of Michigan; Universidad Del Norte. 2017. "Experimental study of flat plate cooling using draft induced by a submerged radial jet." Revista Facultad de Ingeniería Universidad de Antioquia , no. 83: 57-64.
A 2D computational fluid dynamics simulation was carried out using a multiphase flow model with an Eulerian–Eulerian approach for a microalgae culture in an airlift column photobioreactor. Simulation was performed for a \(0.0625\,l/l_{\mathrm{culture}}\cdot \hbox {min}\) inlet airflow. Air, water and microalgae velocity contours showed less gas phase present in the downcomer than in the riser, suggesting the necessity of vigorous mixing in the ascendant portion if homogeneous water and solid flow is to be achieved. Air velocity is smaller in the downcomer (shorter velocity vectors) than in the riser. Water velocity vectors point always in the expected direction, down in the downcomer and up in the riser. Microalgae paths, perhaps due to the small size of the microorganisms, follow the water velocity vectors. As there are fewer hydraulic restrictions to the liquid phase in the riser, a large amount of energy is dissipated by gas–liquid interactions. In the downcomer region, the gas phase is almost nonexistent, and bubble collisions are almost nonexistent as well. A quasi-stagnation zone was found at the lower section of the downcomer, showing that the design requires improvement. Finally, the turbulent kinetic energy is larger at the top and middle region of the riser; meanwhile, it is lower at the downcomer. Similar results were observed for the energy dissipation rate.
Fernando Calvo; Antonio Bula; Leonardo Di Mare; Samira Garcia. CFD simulation of multiphase (liquid–solid–gas) flow in an airlift column photobioreactor. Acta Mechanica 2017, 228, 2413 -2427.
AMA StyleFernando Calvo, Antonio Bula, Leonardo Di Mare, Samira Garcia. CFD simulation of multiphase (liquid–solid–gas) flow in an airlift column photobioreactor. Acta Mechanica. 2017; 228 (7):2413-2427.
Chicago/Turabian StyleFernando Calvo; Antonio Bula; Leonardo Di Mare; Samira Garcia. 2017. "CFD simulation of multiphase (liquid–solid–gas) flow in an airlift column photobioreactor." Acta Mechanica 228, no. 7: 2413-2427.