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Ingeniería y Desarrollo Social - INDES

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Effects of Environmental Conditions on Photovoltaic Generation System Performance with Polycrystalline Panels

Mejía Ruiz, Saúl | 2021-10-31

Photovoltaic solar energy is the third most widely used renewable source worldwide, after hydroelectric and wind energy, and this energy source requires experimental and theoretical development in specific topics such as the effect of environmental conditions on energy performance. Thus, this study's main objective was to determine the influence that meteorological conditions have on the performance of solar photovoltaic systems, based on measurements from a measurement station installed in the city of Barranquilla-Colombia, to determine the factors that significantly affect the system’s energy efficiency deviation. The experimental results show a dependence of the solar panel energy performance on some weather conditions, which is an uncontrolled phenomenon such as the ambient temperature and the atmosphere's humidity. Also, solar panel temperature and irradiance were the parameters with greater importance in the systems power generation. Also, the panel temperature must be controlled to obtain the desired response, because the panel temperature is inversely proportional to the voltage and directly proportional to the current. However, the negative effect of increased panel temperature in sunny climates is compensated by increased solar hours, so the summer system has less instantaneous efficiency, but it has higher solar output throughout the day. Therefore, solar energy production study should be related to total daily production.

Estudio experimental de la sustitución parcial de Diésel con Hidroxy en motores de encendido por compresión y su influencia en las prestaciones térmicas y ambientales.

Prada Botia, Gaudy Carolina | 2020-02-02

Las emisiones de los gases de efecto invernadero, han puesto en riesgo la vida en nuestro planeta tal como hoy la conocemos. Un aumento de la temperatura global de dos grados al final del siglo provocará daños irreversibles a la atmosfera, aumentando el nivel de los océanos debido al descongelamiento acelerado, y en mayor medida, de los polos. El hidrógeno ha sido categorizado como la mejor alternativa para mitigar los problemas que conllevan el uso de combustibles fósiles en Motores de Combustión Interna, ya que no contiene Carbono y adicionalmente, en masa, contiene 3 veces más energía que el combustible diésel. Asimismo, el hidrógeno como elemento se encuentra en abundancia en la naturaleza, está presente en el aire, agua y biomasas. El presente trabajo de investigación propone el estudio experimental del impacto en las prestaciones mecánicas, térmicas y ambientales a causa de la sustitución parcial de combustible Diésel por Hidroxy (HHO) en motores térmicos de encendido por compresión. Para la generación de Hidroxy se utilizó un electrolizador alcalino, en donde se verificaron las condiciones operacionales que permitieran aumentar la tasa de generación de la misma. Se estudiaron diferentes niveles de potencia y velocidad de giro en el motor Diésel, con el fin de analizar estadísticamente la influencia de tasa de sustitución sobre el desempeño del motor. La propuesta conllevara a hacer viable la tecnología para la mejora en el proceso de combustión de los actuales motores diésel y reducir su impacto ambiental.

Análisis termodinámico y económico de sistemas de recuperación de calor residual de un motor de generación mediante tecnologías de ORC

Acevedo Peñaloza, Carlos Humberto | 2020-02-02

Debido a los problemas que se han presentado por el uso excesivo de las fuentes de energía renovables se hace necesario investigar e incluir las nuevas alternativas energéticas, sin embargo, su implementación es costosa por lo cual es de vital importancia la investigación en la mejora de los mismo. Dentro de estos, se destaca el uso de sistema de recuperación de calor residual debido a la fácil adaptación que poseen, sin embargo, el uso racional de estos sistemas no garantiza un desarrollo amigable y/o sostenible medio ambientalmente. Este trabajo presenta un análisis exergo ambiental avanzado a un sistema de recuperación de calor ORC acoplado a un motor de combustión interna con evaporación indirecta con el fin de determinar la magnitud de cada componente de la planta y de esta manera identificar el potencial real de mejora. La exergía destruida es divida en 4 categorías: endógeno, exógeno, evitable e inevitable a su vez que son dividas en endógeno evitable e inevitable y exógeno evitable e inevitable. Con el fin de hacer el sistema mucho más eficiente se aplica un análisis de sensibilidad a las variables con mayor influencia en el sistema para denotar las oportunidades de mejora desde el punto de vista ambiental. Por último, un análisis de ciclo de vida es aplicado para determinar los impactos y dimensiones ambientales a lo largo de la vida útil del sistema.

Caracterización térmica de mezclas de arcillas utilizadas en la fabricación de productos de mampostería para la construcción

García León, Ricardo Andres | 2018

Actualmente en Norte de Santander existe gran variedad de yacimientos naturales que se pueden utilizar para fabricar productos de mampostería para la construcción como lo son bloques, tejas,ladrillos, baldosas, entre otros; pero las empresas fabricantes obtienen muchos desperdicios debido a la falta de análisis tecnológicos de la materia prima para pronosticar el comportamiento de las pastas cerámicas y lograr mejorar la calidad del productofinal. En el presente trabajo se realizó las caracterizaciones térmicas de dos mezclas de arcillas (m7 y m8) encontradas experimentalmente utilizando el método de moldeo de extrusión y en polvo para la fabricación de bloques H-10 tomando como muestra la materia prima (arcilla) de una empresa dedicada a la fabricación de bloques H-10 en Ocaña, Norte de Santander. El desarrollo de la investigación se llevó a cabo mediante la ejecución de ensayos térmicos a las muestras de arcillas con los que se determinaronlos porcentajes pérdida de peso respecto a las temperaturas obtenidas en un diagrama con las curvas de ATD y ATG. Los resultados obtenidos demuestran que las mezcla m7 encontrada experimentalmente presenta mejores características en el proceso de cocción por lo que se estableció una curva de cocción óptima para la fabricación del bloque H-10 teniendo en cuenta las especificaciones del proceso productivo y la materia prima, con lo que se espera mejorar la calidad del producto final cumpliendo las especificaciones de las normas actuales vigentes. Es indispensable caracterizar las arcillas para optimizar la pasta de producción y evitar imperfecciones en el producto final (Bloque H-10) con lo que evidentemente se mejoraran los recursos ambientales y económicos de la empresa.

Experimental study of the cutting processes effect on the surface hardness of ASTM A36 steel

Peralta Hernandez, Edwin | 2018-05-30

This article analyses the hardness of ASTM-A36 steel both in its delivery state and after various cutting processes. The material was cut with different methods conventionally used in the metal-mechanic and construction industry, in addition to other non-conventional processes used to a lesser extent in the industry. In addition, similar cuts were made to maintain test homogeneity and to analyze the faces of the cut on each specimen in a similar manner. Among the conventional cuts made to the specimens are the milling machine, oxy-cutting and cutting machine, while the non-conventional ones were applied by EDM and plasma, maintaining as far as possible similar cutting and working parameters. Subsequently, the hardness of the cut surface of each of the specimens was studied using an AFFRI 250 DMRC durometer, which allowed quantifying the changes in the material depending on the cutting method used and defining according to each method that may affect the final application of the material. The graphical results allowed a comparative analysis of all the methods used, as well as the differences found between them and to obtain important conclusions that can be used in the new techniques of the manufacturing processes.

Experimental study of the cutting processes on the microstructure of an ASTM A36 steel

Peralta Hernandez, Edwin | 2018-06-25

This article analyses the microstructure of ASTM-A36 steel both in its delivery state and after various cutting processes. The material was cut with some methods conventionally used in the metal-mechanical and construction industry, in addition to other non-conventional processes used to a lesser extent in the same industry. Similarly, similar cuts were made to maintain test homogeneity and to analyze the faces of the cut on each specimen in a similar manner. Among the conventional cuts made to the specimens are the milling, oxy-cutting and cutting machine, while the unconventional cuts applied were the wire by EDM and plasma, maintaining as far as possible similar cutting and working parameters. Subsequently, the cut surface of each of the specimens was analyzed and microscopic images of their microstructure were taken, from the results differences were established and it was defined which of the cutting methods used had the greatest effect on the material.

Experimental study of the effect of cutting processes on the roughness of ASTM A36 steel

Peralta Hernandez, Edwin | 2018-06-06

This article analyses the roughness of ASTM-A36 steel both in its delivery state and after various cutting processes. The material was cut with different methods conventionally used in the metal-mechanic and construction industry, in addition to other non-conventional processes used to a lesser extent in the industry. Similarly, similar cuts were made to maintain test homogeneity and to analyze the faces of the cut on each specimen in a similar manner. Among the conventional cuts made to the specimens are the milling machine, oxy-cutting and cutting machine, while the non-conventional ones were applied by EDM and plasma, maintaining as far as possible similar cutting and working parameters. Subsequently, the roughness of the cut surface of each of the specimens was studied using a BAKER K130/8 analog tape roughness meter, which allowed quantifying the changes that occur in the material depending on the cutting method used and defined according to each method that can affect the surface finish and therefore the final application of the material. The graphical results allowed a comparative analysis of all the methods used, as well as the differences found between them and to obtain important conclusions that can be used in the new techniques of the manufacturing processes.

Technical-economic study of the feed per tooth influence in a cylindrical milling process of alloyed steels

Coba Salcedo, Milton Fabian | 2018-07

The economy of the machining process is an important point that has been given attention since the beginning of the process. For this reason, this study focuses on the evaluation of the performance of the cylindrical milling process, varying the feed rate per tooth for the operating conditions proposed in the revised case study. This was done using a calculation algorithm in which the fixed parameters were entered and the feed per tooth was varied. Finding benefits in terms of cutting speed, feed speed, cutting time and more. Increased feed per tooth resulted in lower process costs.

Theoretical modeling of a steam power cycle using an interactive computational tool

Lizarazo Bohórquez, Cristina | 2018-07

This paper presentsan energetic and exergetic analysis for ageneration of turbine work according to the variation of the pressure in the condenser regenerative Rankine cycle, implementing an educational graphical user interface known as Power Cycle version 2.0; that is used as a pedagogical strategy in thefield ofengineering education. The mains objectives were, analyzethe efficiency of first and second thermodynamic law, and the generation of turbine work according to the variation of thecondenser pressure, at three different temperatures in the boiler, as well as analyzing the components of the system to identify and quantify where the exergy destruction was maximum. According to the results in the cases studied, the percentage ratio of the exergydestruction to the total exergy destruction was found to be maximum in the boiler 62.18%, then the turbine 22.79%, and finally 15.03% in the pumps, the heater and the condenser. On the other hand, the maximum calculated thermal efficiency was 38.34%, while the maximum exergetic efficiency was 62.81%. A significant increase in efficiency of the cycle is obtained by decreasing the pressure in the condenser.

Validation of a non-conservative mechanical model applied to the low energy impact phenomenon

Coba Salcedo, Milton Fabian | 2018-07-17

The impact of materials is undoubtedly the object of research, due to the dynamic condition inherent in the bodies that interact in our universe. This work places special emphasis on the method of plate bending, which, due to its geometric configuration, interprets real impact situations to which some bodies are subjected, in addition to the low energy technique in which the energy available in the impactor is less than that absorbed in the breaking process, makes it possible to obtain information on the material in the elastic, plastic, initiation and crack propagation range. For research, the contribution of technological progress in instrumented test equipment by electronics is important, as it allows us to record much more information on the evolution of the contact between the impactor and the sample step by step. This information must be further processed and this phase of the research requires programming, modelling and simulation of the test dynamics to interpret or even predict the different phenomena that converge in the fraction of time in which the impact occurs. In this sense, our objective has been to study the physical behavior of different thermoplastic materials and their response to impact requests and to develop a series of models that try to simulate the phenomenon, in order to help us establish what happens at each stage of it, this is achieved using powerful mathematical tools, new contributions from the scientific community and continuous experimentation achieved in the laboratory. So that more knowledge can be obtained in this field.

Analysis of research trends in biodiesel as fuel during last decade

Valencia Ochoa, Guillermo Eliecer | 2018

This paper presents a bibliometric study focused on the research carried out in the last 11 years on biodiesel as an alternative fuel. Tools such as HistCite were used to manage metadata found using the Web of Science search engine, including author names, titles, abstracts, publication dates, document types, addresses and references cited. In addition, the impact factor and H index of the journals they published were taken into account to analyze the reliability of the research. The study showed a tendency to increase over the years, from 76 publications in 2007 to a total of 2017 in 2017, an increase of 185.71%. Likewise, it was concluded, among other things, that of the 1423 documents obtained to carry out the study, 84.7% were scientific articles, being the majority of the works carried out, followed by the revisions that reached 5.8%. And that magazines such as FUEL, ENERGY & FUEL and ENERGY were among those that contributed the most to this research. In addition, it was demonstrated that the countries most interested in this technology are India, USA and Peoples R China, being these the ones with more than 254, 222 and 119 publications respectively.

Effects of depth of cut on cylindrical milling process in steel casting: A numerical study

Coba Salcedo, Milton Fabian | 2018

The complexity of the milling process has led us to study different parameters, among which are the cutting speed, feed speed, chip volume, cutting time and associated costs, which are the focus of this study. For this purpose, a calculation algorithm was designed in which fixed parameters were left and the cutting depth was varied from 2 to 8 mm. This resulted in an increase in process times and costs, which was expected due to the removal of more material and a negative impact on the surface finish of the part.

Análisis térmico, modelamiento matemático y simulación de un reactor de agitación discontinuo para volumen específico

Rolon, Humberto | 2019-01-01

El presente trabajo expone el análisis térmico y el modelamiento matemático de un reactor de agitación discontinuo. Se implementó una fase de adquisición de datos en cuanto alfuncionamiento y la utilidad de los reactores de agitación. Posteriormente, se aplicaron los conceptos de termodinámica, mecánica de fluidos, transferencia de calor y transporte de materia,para realizar el respectivo análisis térmico,y así determinar la energía contenida y transferida en los fluidos utilizados.Por último, se dedujoun modelo matemático en el softwareEES,para comprobar su comportamiento,teniendo en cuenta las variables operativas sometidas a diversos tipos de fluidos. Además, se simuló el entorno físico-químico del reactor,para validar los datos calculados y compararlos con los valores experimentales, relacionando la geometría del equipo con las condiciones de trabajoy las especificaciones del producto final.

Bibliometric analysis of the thermal storage systems research in the last ten years

Peralta-Ruiz, Yeimmy | 2018

In this research we analyze the state of the art of the technological developments that are being presented by the scientific community to mitigate the strong environmental changes with renewable energies. The results obtained by the bibliometric techniques in the period 2007-2018 show that in the 1900 published articles the People's Republic of China presents the highest volume of 32.3% of the total publications, showing a strong influence on the development of energy storage technologies and the availability of materials. The results presented in this article allow us to evaluate the development of researchers in this alternative of energy storage as a replacement to the distribution that is done with traditional methods.

Experimental characterization of the mechanical properties of PETG and PA6 thermoplastics

Coba Salcedo, Milton Fabian | 2018-09-12

Simple thermoplastic materials and polymer matrix composites have been used in this work. Polyethylene terephthalate glycol (PETG) plates, a copolymer of CHDM- cyclohexane dimethanol modified polyethylene terephthalate [56], were used, which is an amorphous and therefore transparent material, which was available in plates or extruded sheets in a wide range of thicknesses. The PETG sheets are of commercial type and their production process is carried out by the company that supplied them. Also part of the study is polyamide 6.6 with 30% short glass fibre content obtained by injection moulding and compression moulding, which was supplied by the ESIS TC4, for the first Round Robin of short glass fibre composite materials.

Experimental model of the fine honing

Coba Salcedo, Milton Fabian | 2018

An experimental model of the honing process oriented towards the honing operation for very fine finished is development. A two-level design of experiments has been carried out with three factors and a replica. We chose the factors that have been shown to be most significant in honing machining such as grain size and pressure. In addition, as in honing, the angle of scratching is important and depends on the relationship between the two speeds, linear velocity VL and tangential velocity VT, one of them has also been chosen, the linear velocity VL, and the other velocity VT is kept constant. By varying only VL, the scratch angle is varied and the tangential speed VT is kept constant, the number of factors is reduced and the number of tests is reduced. The variable with the greatest influence and which is present in a significant way in all the output parameters is the abrasive grain size Gst, the pressure parameters P and linear velocity VL did not show to be particularly decisive in the finishing phase, especially for the roughness parameters. Manufacturers of hydraulic cylinders, surface finish of the inner wall of internal combustion engines and all those applications where it is machined with honing

Influence of indenter diameter on dynamic indentation tests of PEGT and PA6 thermoplastics

Coba Salcedo, Milton Fabian | 2018-09-18

In this article the results of the impact characterization of PETG and PA6 thermoplastics are presented, they have been characterized statically and dynamically by the indentation test, and mathematical models developed in previous works have also been used to adjust the obtained models. The Indenter diameter of the impactor used were studied. The results have shown that the specimen thickness influences the value of some of the measured properties as the thickness increases, as well as that the impactor mass influences the velocity that is printed during the test run.

Mechanical characterization of impact resistance by pendulum tensile test on PETG and PA6 thermoplastics

Coba Salcedo, Milton Fabian | 2018-09-18

This article presents the results of the mechanical characterization of the impact resistance of PETG and PA6 thermoplastic polymers. This type of polymer is being widely used in industrial applications and the characterization of its mechanical properties is a subject of great academic and industrial interest. The impact pendulum technique has been used as the most widely known. The tests have been carried out under different conditions and varying the greatest number of parameters in order to obtain data that allow a rigorous characterization of these materials.

A bibliometric analysis environmental impact assessment literature: An expanding and shifting focus

Coba Salcedo, Milton Fabian | 2018-09

A bibliometric analysis of the literature on the subject of Environmental Impact Assessment for a period from 2007 to 2015 was carried out under an expanding and shifting focus. For this purpose, the metadata used was obtained through web of science and analyzed with the Histcite software. The search identified a total of 683 publications related to Environmental Impact Assessment in the period studied, allowing to study the main journals involved in this topic. The country with the highest number of publications was the United States with 88 papers on the subject. On the other hand, the journal with the greatest influence on the subject was Environmental Impact Assessment Review, with 1090 citations, representing the 8.7% of the total citations between 2007 and 2015. Analyzing the evolution of publications per year, there was an increase in research activity on the subject between 2012 and 2014, amounting to 45.6% in those years. According to the type of document from the 683 publications, the 84.6% (578) were articles and 4.4% reviews. These results obtained show an increase in the interest of researchers in the environmental impact assessment topic, which is in line with the climate changes presented on the planet and the global concern to reduce the effects of greenhouse gas, and the better use of natural resources.

Caracterización Térmica de mezclas de arcillas utilizadas en la fabricación de productos de mampostería para la contrucción

García León, Ricardo Andrés | 2018

Actualmente en Norte de Santander existe gran variedad de yacimientos naturales que se pueden utilizar para fabricar productos de mampostería para la construcción como lo son bloques, tejas, ladrillos, baldosas, entre otros; pero las empresas fabricantes obtienen muchos desperdicios debido a la falta de análisis tecnológicos de la materia prima para pronosticar el comportamiento de las pastas cerámicas y lograr mejorar la calidad del producto final. En el presente trabajo se realizó las caracterizaciones térmicas de dos mezclas de arcillas (m7 y m8) encontradas experimentalmente utilizando el método de moldeo de extrusión y en polvo para la fabricación de bloques H-10 tomando como muestra la materia prima (arcilla) de una empresa dedicada a la fabricación de bloques H-10 en Ocaña, Norte de Santander. El desarrollo de la investigación se llevó a cabo mediante la ejecución de ensayos térmicos a las muestras de arcillas con los que se determinaron los porcentajes pérdida de peso respecto a las temperaturas obtenidas en un diagrama con las curvas de ATD y ATG. Los resultados obtenidos demuestran que las mezcla m7 encontrada experimentalmente presenta mejores características en el proceso de cocción por lo que se estableció una curva de cocción óptima para la fabricación del bloque H-10 teniendo en cuenta las especificaciones del proceso productivo y la materia prima, con lo que se espera mejorar la calidad del producto final cumpliendo las especificaciones de las normas actuales vigentes. Es indispensable caracterizar las arcillas para optimizar la pasta de producción y evitar imperfecciones en el producto final (Bloque H-10) con lo que evidentemente se mejoraran los recursos ambientales y económicos de la empresa.