Mostrando ítems 1-20 de 27

Advance Exergo-Economic Analysis of a Waste Heat Recovery System Using ORC for a Bottoming Natural Gas Engine

Valencia Ochoa, Guillermo; Rojas Suárez, Jhan Piero; Duarte Forero, Jorge (EnergiesBerna , Suiza, 2020-01-05)

This manuscript presents an advanced exergo-economic analysis of a waste heat recovery system based on the organic Rankine cycle from the exhaust gases of an internal combustion engine. Different operating conditions were ...
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, ...
Carbon footprint analysis and advanced exergo-environmental modeling of a waste heat recovery system based on a recuperative organic Rankine cycle

Prada Botia, Gaudy Carolina; Valencia Ochoa, Guillermo; Duarte Forero, Jorge (Journal of Cleaner ProductionReino Unido, 2020-07-17)

The excessive and irrational use of non-renewable energy is the consequence of the interaction of economic growth and environmental pollution. Therefore, it is increasingly necessary to propose energy and environmental ...
A comparative study of the energy, exergetic and thermo-economic performance of a novelty combined Brayton S-CO2-ORC configurations as bottoming cycles

Cárdenas-Gutiérrez, Javier Alfonso; Duarte Forero, Jorge; Valencia Ochoa, Guillermo (HeliyonReino Unido, 2020-07-14)

This paper presents a comparative study on the energy, exergetic and thermo-economic performance of a novelty thermal power system integrated by a supercritical CO2 Brayton cycle, and a recuperative organic Rankine cycle ...
Computer-aided simulation of the energetic and exergetic efficiency of a two-stage cascade cooling cycle

Arrieta Mondragón, Leonardo; Valencia Ochoa, Guillermo; Prada Botia, Gaudy Carolina (International Journal of Applied Engineering ResearchIndia, 2018)

Refrigeration systems are of great importance in industry and are widely used in food preservation or air conditioning. Studies have been carried out in recent years in search of parameters to optimise the cycle by ...
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 ...
Effects of Environmental Conditions on Photovoltaic Generation System Performance with Polycrystalline Panels

Mejía Ruiz, Saúl; Vanegas Chamorroa, Marley; Valencia Ochoa, Guillermo; Fábregas Villegas, Jonathan; Acevedo Peñaloza, Carlos Humberto (International Journal on Advanced Science Engineering and Information Technology, 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 ...
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 ...
Operational data set of a 2 MW natural gas-fired generation engine at shutdown times

Valencia Ochoa, Guillermo; Rojas Suárez, Jhan Piero; Duarte Forero, Jorge (Data in BriefPaíses Bajos, 2020-06)

In this paper, operational data of a natural gas-fired generation engine at 2 MW of power is presented. This engine is used as part of the power supply system of a flexible packaging transformation and conversion plant. ...
Parametric analysis CFD of the hydraulic performance of a centrifugal pump with applications to the dredging industry

Cárdenas-Gutiérrez, Javier Alfonso; Valencia Ochoa, Guillermo; Duarte Forero, Jorge (Journal of Engineering Science and Technology ReviewGrecia, 2020-06-20)

The present study aims to use the analysis of CFD in a centrifugal dredge pump, to predict by mathematical correlations the effect that changes in the main variables of the dredging process would have on the behavior and ...
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 ...

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Advance Exergo-Economic Analysis of a Waste Heat Recovery System Using ORC for a Bottoming Natural Gas Engine
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Valencia Ochoa, Guillermo | 2020-01-05

This manuscript presents an advanced exergo-economic analysis of a waste heat recovery system based on the organic Rankine cycle from the exhaust gases of an internal combustion engine. Different operating conditions were established in order to find the exergy destroyed values in the components and the desegregation of them, as well as the rate of fuel exergy, product exergy, and loss exergy. The component with the highest exergy destroyed values was heat exchanger 1, which is a shell and tube equipment with the highest mean temperature difference in the thermal cycle. However, the values of the fuel cost rate (47.85 USD/GJ) and the product cost rate (197.65 USD/GJ) revealed the organic fluid pump (pump 2) as the device with the main thermo-economic opportunity of improvement, with an exergo-economic factor greater than 91%. In addition, the component with the highest investment costs was the heat exchanger 1 with a value of 2.769 USD/h, which means advanced exergo-economic analysis is a powerful method to identify the correct allocation of the irreversibility and highest cost, and the real potential for improvement is not linked to the interaction between components but to the same component being studied.

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

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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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Carbon footprint analysis and advanced exergo-environmental modeling of a waste heat recovery system based on a recuperative organic Rankine cycle
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Prada Botia, Gaudy Carolina | 2020-07-17

The excessive and irrational use of non-renewable energy is the consequence of the interaction of economic growth and environmental pollution. Therefore, it is increasingly necessary to propose energy and environmental improvements in the energy conversion systems according to sustainable development goals, especially in internal combustion engines. The exergetic analyses are a great tool because they allow identifying the components of greater irreversibilities. However, sustainable continuous improvement and opportunities can be found only by means of its advanced development. The study showed that in the waste heat recovery of a 2 MW gas engine based on the recuperative organic Rankine cycle (RORC) using R123 as working fluid, much of the exergy destroyed was endogenous 105.08 kW (81.6%). Steel, copper and aluminum were the proposed materials for the construction of the components, and through a life cycle analysis, it was found that the significant environmental impacts were found in the turbine for the aluminum with a value of 27617.21 kg of CO2 equivalent. Through the carbon footprint and advanced exergo-environmental analysis, it was found that the heat exchanger 1 is the equipment with the largest endogenous exergy destruction opportunities for improvement, also is the heat exchanger device with the most significant rate of environmental impacts, and the recommended material to use in the construction phase of the life-time of the system is the aluminum.

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A comparative study of the energy, exergetic and thermo-economic performance of a novelty combined Brayton S-CO2-ORC configurations as bottoming cycles
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Cárdenas-Gutiérrez, Javier Alfonso | 2020-07-14

This paper presents a comparative study on the energy, exergetic and thermo-economic performance of a novelty thermal power system integrated by a supercritical CO2 Brayton cycle, and a recuperative organic Rankine cycle (RORC) or a simple organic Rankine cycle (SORC). A thermodynamic model was developed applying the mass, energy and exergy balances to all the equipment, allowing to calculate the exergy destruction in the components. In addition, a sensitivity analysis allowed studying the effect of the primary turbine inlet temperature (TIT, PHIGH, rP and TC) on the net power generated, the thermal and exergy efficiency, and some thermo-economic indicators such as the payback period (PBP), the specific investment cost (SIC), and the levelized cost of energy (LCOE), when cyclohexane, acetone and toluene are used as working fluids in the bottoming organic Rankine cycle. The parametric study results show that cyclohexane is the organic fluid that presents the best thermo-economic performance, and the optimization with the PSO method conclude a 2308.91 USD/kWh in the SIC, 0.22 USD/kWh in the LCOE, and 9.89 year in the PBP for the RORC system. Therefore, to obtain technical and economic viability, and increase the industrial applications of these thermal systems, thermo-economic optimizations must be proposed to obtain lower values of the evaluated performance indicators.

LEER
Computer-aided simulation of the energetic and exergetic efficiency of a two-stage cascade cooling cycle
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Arrieta Mondragón, Leonardo | 2018

Refrigeration systems are of great importance in industry and are widely used in food preservation or air conditioning. Studies have been carried out in recent years in search of parameters to optimise the cycle by reducing losses, both to increase the COP and to reduce energy consumption, so that process improvements have been made from which different cycles are derived, such as the gas cooling cycle with regeneration, absorption cooling, gas liquefaction or multistage compression cooling systems. This document presents a combined refrigeration system consisting of two vapour compression refrigeration cycles linked by a heat exchanger that not only reduces the work of the compressor but also increases the amount of heat absorbed by the refrigerated space as a result of the cascade stages and improves the COP of a refrigeration system. The study was carried out under the assumption of a stationary flow, and without significant changes in the kinetic and potential energy, i.e. assuming an ideal process, carrying out several case studies with the help of UNISIM, evaluating the effect of varying the low temperature on the exergetic efficiency, the destroyed exergy of the condenser, the net input work and the COP, as well as the influence of the input pressure in the upper cycle compressor on the net input work and the COP.

LEER
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.

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

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.

LEER
Experimental study of the correlation the surface roughness 2D and 3D in the honing process of the steel cylinder
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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

LEER
Experimental study of the cutting processes effect on the surface hardness of ASTM A36 steel
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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
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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
Operational data set of a 2 MW natural gas-fired generation engine at shutdown times
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Valencia Ochoa, Guillermo | 2020-06

In this paper, operational data of a natural gas-fired generation engine at 2 MW of power is presented. This engine is used as part of the power supply system of a flexible packaging transformation and conversion plant. This plant, besides having the power supply generated by the engine, receives electrical energy from the network. The data collected from this engine corresponds to measurements taken before, during and after engine stops, whether due to engine maintenance stops, engine failures or external power grid failures. The measurement was made every 10 seconds, and for the storage of these data a data acquisition software was used, which, besides allowing to take these data, shows in real time the electrical behavior of the electrical supply system, as well as the mechanical behavior of the engine.

LEER
Parametric analysis CFD of the hydraulic performance of a centrifugal pump with applications to the dredging industry
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Cárdenas-Gutiérrez, Javier Alfonso | 2020-06-20

The present study aims to use the analysis of CFD in a centrifugal dredge pump, to predict by mathematical correlations the effect that changes in the main variables of the dredging process would have on the behavior and efficiency of the pump. The OpenFOAM® open source software is used for the development of the study, through which a series of operating conditions that the dredging pump experiences in its operation were reproduced. The information collected from the output variables in the pump allowed us through statistical analysis, the development of mathematical correlations that allow us to directly identify the relationships between the process variables and their influence on the pump behavior (suction pressure, discharge pressure, total dynamic head, NPSHr and efficiency). The results obtained indicate that the simulation process allows a high prediction to be obtained with respect to the actual pump conditions (error below 4%). Mathematical correlations demonstrated efficiency for the operating range of work from 83% to 64%. Additionally, the NPSHr analysis allows defining operating limits that avoid adverse effects such as cavitation.

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.

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Probability parameters and estimated firestone abbott plateau honing curves
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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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