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

Coba Salcedo, Milton Fabian; Valencia Ochoa, Guillermo; Acevedo Peñaloza, Carlos Humberto (Chemical Engineering TransactionsItalia, 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 ...
Bibliometric analysis of the thermal storage systems research in the last ten years

Peralta-Ruiz, Yeimmy; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (International Journal of ChemTech ResearchIndia, 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 ...
Bibliometric science indicators applied to environmental impacts research

Peralta-Ruiz, Yeimmy; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (Contemporary Engineering SciencesBulgaria, 2018-08-01)

The growth and development of research on environmental impacts in terms of publications such as the Web of Science sample are analyzed during the period 2007-2018 using HistCite to learn about a global ranking, citations, ...
Effect of the mass flow rate on the heat transfer phenomena in a shell and tube heat exchanger

Delgado Ruiz, Leonardo; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (International Journal of Applied Engineering ResearchIndia, 2018)

This article presents the development of some case studies on shell and tube heat exchangers using a graphical interface developed in MATLAB®. Through the case studies, the variation in the performance of the equipment ...
Effects of depth of cut on cylindrical milling process in steel casting: A numerical study

Coba Salcedo, Milton Fabian; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (International Journal of ChemTech ResearchIndia, 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 ...
Exergetic Evaluation of a Rankine Cycle with Regeneration: Effect of Turbine Inlet Temperature and Source Temperature

Arrieta Mondragón, Leonardo; Valencia Ochoa, Guillermo; Acevedo Peñaloza, Carlos Humberto (International Journal of Applied Engineering ResearchIndia, 2018)

The Rankine cycle is a thermodynamic cycle widely used in power plants, specifically in steam power plants, due to its great importance in the industry. It has also been studied in recent years in search of parameters that ...
Experimental study of the correlation the surface roughness 2D and 3D in the honing process of the steel cylinder

Coba Salcedo, Milton Fabian; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (Indian Journal of Science and Technology ISSNIndia, 2018-08)

Objectives: This research proposes the feasibility of working on surfaces obtained by honing with 2D roughness parameters, as the 3D roughness measurement commonly used in the industry requires many hours of measurement time. ...
Experimental study of the cutting processes effect on the surface hardness of ASTM A36 steel

Peralta Hernandez, Edwin; Sorzano Jimenez, Francisco; Coba Salcedo, Milton Fabian; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (Contemporary Engineering SciencesBulgaria, 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 ...
Experimental study of the cutting processes on the microstructure of an ASTM A36 steel

Peralta Hernandez, Edwin; Sorzano Jimenez, Francisco; Coba Salcedo, Milton Fabian; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (Contemporary Engineering SciencesBulgaria, 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 ...
Experimental study of the effect of cutting processes on the roughness of ASTM A36 steel

Peralta Hernandez, Edwin; Sorzano Jimenez, Francisco; Coba Salcedo, Milton Fabian; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (Contemporary Engineering SciencesBulgaria, 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 ...
PEST analysis of a rankine organic cycle for energy recovery

Valencia Ochoa, Guillermo; Acevedo Peñaloza, Carlos Humberto; Mendoza-Casseres, Daniel (International Journal of Applied Engineering ResearchIndia, 2018)

In this work is presented a state of the art of political and economic investments, technological developments, social and environmental impacts of the 4 countries that contribute more research on the Organic Rankine ...
Probability parameters and estimated firestone abbott plateau honing curves

Coba Salcedo, Milton Fabian; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (Contemporary Engineering SciencesBulgaria, 2018-09-12)

This paper developed a methodology for estimating Abbott-Firestone curves from the roughness parameters of the material probability curves. The surface roughness profile obtained in plateau-honing processes is the ...
Regenerative chatter Phenomenon in the Turning Process based on the alloy steels 1020, 1035 and 1045

Coba Salcedo, Milton Fabian; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (International Journal of ChemTech ResearchIndia, 2018)

Regenerative vibration is a major drawback in machining processes reducing the geometric accuracy and dynamic stability of the cutting system. Achieving a dynamically stable cutting operation represents a significant ...
Regenerative reassembly phenomenon in the turning process machining the A1020 steel

Coba Salcedo, Milton Fabian; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (Contemporary Engineering SciencesBulgaria, 2018-08-01)

The chattering in the machine tools is a phenomenon that causes instability in the machining process, surface finish with high roughness, also produces excessive and accelerated wear on the tool in the metal cutting ...
A Semi-Physical Modeling of the Combustion Chamber and Inlet Manifold of a 2 MW Natural Gas Generation Engine

Valencia Ochoa, Guillermo; Duarte Forero, Jorge; Acevedo Peñaloza, Carlos Humberto (International Review on Modelling and SimulationsItalia, 2020-02)

This article presents a sensitivity analysis based on a validated model of average value in natural gas generation engines under the phenomenologically based semi-physical modeling methodology, which includes both the ...
Study of the emissions in the diesel engines: A review

Duarte Forero, Jorge; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (Contemporary Engineering SciencesBulgaria, 2018-09-12)

Diesel engines are one of the main sources to supply the rapid growth of energy consumption worldwide. They have been widely used in the public and commercial transport sector due to their greater durability and efficiency. ...
Technical-economic study of the feed per tooth influence in a cylindrical milling process of alloyed steels

Coba Salcedo, Milton Fabian; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (International Journal of Engineering and TechnologyIndia, 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 ...
Theoretical modeling of a steam power cycle using an interactive computational tool

Lizarazo Bohórquez, Cristina; Acevedo Peñaloza, Carlos Humberto; Valencia Ochoa, Guillermo (International Journal of Engineering and TechnologyIndia, 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 ...

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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.

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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.

LEER
Bibliometric science indicators applied to environmental impacts research
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Peralta-Ruiz, Yeimmy | 2018-08-01

The growth and development of research on environmental impacts in terms of publications such as the Web of Science sample are analyzed during the period 2007-2018 using HistCite to learn about a global ranking, citations, article impact, keywords and research trends in this area. The research trend increased during the years 2014 and 2017. The United States is the country with the highest number of publications. The Journal of Cleaner Production is the journal with the highest number of publications, along with Science of Total Environment and the Environmental impact assemble review.

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Effect of the mass flow rate on the heat transfer phenomena in a shell and tube heat exchanger
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Delgado Ruiz, Leonardo | 2018

This article presents the development of some case studies on shell and tube heat exchangers using a graphical interface developed in MATLAB®. Through the case studies, the variation in the performance of the equipment was determined by means of the heat transfer coefficient in function of some parameters such as mass flow and tube arrangements, establishing initial conditions for each run that were established in the software. Likewise, the article shows in detail the methodology with which the study was developed, the fundamental equations used to calculate these results and the graphs obtained. Through this study, it was verified that the variables studied had such an influence on the parameters evaluated, with the objective of establishing selection and operation criteria when designing a shell and tube heat exchanger.

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

LEER
Exergetic Evaluation of a Rankine Cycle with Regeneration: Effect of Turbine Inlet Temperature and Source Temperature
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Arrieta Mondragón, Leonardo | 2018

The Rankine cycle is a thermodynamic cycle widely used in power plants, specifically in steam power plants, due to its great importance in the industry. It has also been studied in recent years in search of parameters that can optimize the cycle by reducing losses and thus increase efficiency, so that improvements have been made in the process such as overheating of steam at the turbine inlet, and even regeneration of water at the boiler inlet. In this work a process of optimization of a Rankine cycle was presented by complementing it with an open feed water heater which not only improves the efficiency of the cycle, but also provides a convenient means of de-aeration of the feed water to prevent corrosion in the boiler, in which it was carried out under the assumption of a stationary flow, and without significant changes in the kinetic and potential energy, that is, assuming an ideal process, all this with the aim of obtaining the highest thermal efficiency and the lowest exergetic losses in the cycle, carrying out several case studies with the assistance of Unisim with temperature variations at the turbine inlet and at the source to observe how this affects the exergetic efficiency and exergy destroyed in the turbine and it was concluded that this is reflected in the production of mechanical energy useful for creating electrical energy because a variation in these parameters could cause job losses in the turbine and decrease in the exergetic efficiency of the system which in turn would lead to a decrease in the network of the system.

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Experimental study of the correlation the surface roughness 2D and 3D in the honing process of the steel cylinder
...
Coba Salcedo, Milton Fabian | 2018-08

Objectives: This research proposes the feasibility of working on surfaces obtained by honing with 2D roughness parameters, as the 3D roughness measurement commonly used in the industry requires many hours of measurement time. Methods/Statistical Analysis: In this article, we study the values of surface roughness in two dimensions and three dimensions measured inside cylinders, machined by honing in industrial honing machines. Hardness has been measured with a contact probe roughness meter, as this type of instrument is widely used in academic and especially industrial applications and is standardized in international standards such as ISO 3274 or ASME B46.1. Findings: It is concluded that due to the excellent association obtained, it is sufficient to work with adjustments in two dimensions to characterize the surface, since the roughness in three dimensions takes a long time to be measured with a contact roughness meter like the one used in this investigation, so 2D parameters can be used because due to their normal behavior, they offer competitive advantages due to their ease of determination and require shorter measurement times. Application/Improvements: Manufacturers of hydraulic cylinders, surface finish of the inner wall of internal combustion engines and all those applications where it is machined with honing

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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.

LEER
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.

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

LEER
PEST analysis of a rankine organic cycle for energy recovery
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Valencia Ochoa, Guillermo | 2018

In this work is presented a state of the art of political and economic investments, technological developments, social and environmental impacts of the 4 countries that contribute more research on the Organic Rankine Cycles (ORC) from the application of PEST analysis. Taking into account that technologies for waste heat recovery such as ORCs have been very popular due to their friendly impact on the environment. Countries such as the People's Republic of China are carrying out a large number of research projects on ORCs with industrial applications, and their policies are in line with the need to reduce greenhouse gas emissions, as evidenced by the Top-1000 Energy-Consuming Enterprises program, which seeks to optimize the systems of the country's main production companies.

LEER
Probability parameters and estimated firestone abbott plateau honing curves
...
Coba Salcedo, Milton Fabian | 2018-09-12

This paper developed a methodology for estimating Abbott-Firestone curves from the roughness parameters of the material probability curves. The surface roughness profile obtained in plateau-honing processes is the superposition of the effects of the two processes used to generate it. At first, a honing is performed with which the characteristics of valleys are generated, honing base, and after this honing base, a finishing honing is performed, a plateau operation to reduce the peaks of the base honing profile without modifying the characteristics of the valleys of the base profile. In the functional behaviour of the surface, the valleys will contribute to the retention of oil and the flat areas will contribute to reducing friction with the oil retained in the valleys and to improving watertightness. To characterize this type of roughness obtained by the superposition of the roughness generated by two processes, material probability curves are suitable, in which the roughness of each process is characterized by the slope of a line, and the point of intersection of both lines corresponds to the transition zone between plateaus and valleys. The roughness parameters other than those of the probability curve do not adequately characterize the roughness obtained by processes such as plateauhoning, since they are calculated on the total height of the roughness profile and do not separate the effects of the processes that have been used to obtain it, which means that the contribution of each of the processes to the roughness profile cannot be differentiated.

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Regenerative chatter Phenomenon in the Turning Process based on the alloy steels 1020, 1035 and 1045
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Coba Salcedo, Milton Fabian | 2018

Regenerative vibration is a major drawback in machining processes reducing the geometric accuracy and dynamic stability of the cutting system. Achieving a dynamically stable cutting operation represents a significant decrease in the production time and therefore in the costs associated with this process. The information provided by the stability lobe diagrams is of great importance, since from them we know the range of spindle rotation speeds and chip thicknesses at which the cutting operation takes place in a state free from the phenomenon of regenerative chatter, avoiding the rapid wear of the cutting tool and achieving quality surface finishes. In the present investigation, the behavior of the turning operations in steel 1020, steel 1035 and steel 1045 is characterized, with the objective of verifying the presence of instability in the machining caused by the regenerative chattering in the machine tools. Based on the analytical models proposed by Altintas and Budak for the stabilization of self-excited vibrations, a computer tool is developed capable of generating stability lobe diagrams, which allow us to appreciate the operating conditions in which machining presents stable behavior, to simulate the material removal process considering certain parameters specific to the machine tool.

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Regenerative reassembly phenomenon in the turning process machining the A1020 steel
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Coba Salcedo, Milton Fabian | 2018-08-01

The chattering in the machine tools is a phenomenon that causes instability in the machining process, surface finish with high roughness, also produces excessive and accelerated wear on the tool in the metal cutting processes, this phenomenon consists of self-excited vibrations which are produced and maintained due to the cutting forces, the purpose of this article is to analyze regenerative chatter and predict the optimal points of operation in the turning process for 1020 carbon steel by developing analytical methods for generating stability lobe diagrams. To achieve this objective, the methods proposed by Altinas and Budak to stabilize the self-excited vibrations in the turning process applied to the orthogonal cut were studied in detail. These methods are widely accepted within the community of researchers and specialists in the field, thanks to the excellent results obtained in practice. Once the models studied were compressed, a computational algorithm was developed with the help of the MATLAB® software that was able to generate stability lobe diagrams for the turning operation in order to find the optimal points of operation so that there was no chatter, thus improving the material removal rate and increasing productivity

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A Semi-Physical Modeling of the Combustion Chamber and Inlet Manifold of a 2 MW Natural Gas Generation Engine
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Valencia Ochoa, Guillermo | 2020-02

This article presents a sensitivity analysis based on a validated model of average value in natural gas generation engines under the phenomenologically based semi-physical modeling methodology, which includes both the cylinder, exhaust, and intake manifold and it can define the average operational variables and thermochemical properties of exhaust gases as a function of the variables instrumented in this type of engine at the industrial level. The results for a month of operation showed errors no greater than 5% in the temperature at the entrance of the cylinders (Temperature 6), while the power, load temperature and load pressure of the model presented deviations of less than 2% from the measured data. Additionally, the results of the sensitivity analysis evidenced that the main variable affecting most of the parameters under study is the flow of gas entering the engine, which causes a variation of 12.3% in Temperature 6, and 22.4% in electrical power. Next, the second most influential variable is Lambda, significantly affecting the efficiency by 8%. Finally, there is the RPM of the engine in its work cycle, which affects the temperature of the cylinder outlet by 34.5%. This means that when the flow of fuel in the engine decreases, there will be significant operational changes in the engine, and therefore in the thermal availability of exhaust gases.

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Study of the emissions in the diesel engines: A review
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Duarte Forero, Jorge | 2018-09-12

Diesel engines are one of the main sources to supply the rapid growth of energy consumption worldwide. They have been widely used in the public and commercial transport sector due to their greater durability and efficiency. The current study in Diesel engines is focused on emissions from exhaust gases, as they are causing problems in human health and the ecosystem, because they contain dangerous substances, such as organic carbon, trace elements, elemental carbon and inorganic ions. In this paper, we study the different investigations on pollutant emissions in engines, focused on the mechanisms of formation of pollutants, the techniques to reduce these emissions and how they affect human health. With this, it will be possible to project the necessary improvements in this type of systems, to reduce the impact of these thermal machines on the environment.

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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.

LEER
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.

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