Mostrando ítems 121-140 de 1541

Experimental study of emissions in single-cylinder diesel engine operating with diesel-biodiesel blends of palm oil-sunflower oil and ethanol

Vergel Ortega, Mawency; VALENCIA OCHOA, GUILLERMO; Duarte Forero, Jorge (Case Studies in Thermal EngineeringReino Unido, 2021-08)

This study investigates an alternative fuel methodology for diesel engines that focus on the influence of ethanol as an additive agent in biodiesel blends derived from the industrial liquid waste of palm oil and sunflower ...
Prefase V International Meeting of Mathematical Education

Vergel Ortega, Mawency; Rincón Leal, Olga Lucy; Dueñas Ramirez, Leidy Marcela (Reino Unido, 2021-05-22)

The objective of the V International Meeting on Mathematics Education (V IMME) is to create and maintain a space that privileges and promotes the culture of mathematics, reflection and discussion on the education and ...
Experimental and CFD Study of a Centrifugal Fan Performance Under ANSI/AMCA Standard

Rojas Suárez, Jhan Piero; Villada Castillo, Dora Clemencia; Flórez Solano, Eder (International Journal on Engineering ApplicationsItalia, 2021)

Centrifugal fans are widely employed for several technical applications in science and engineering due to their easy employment and practical use. Therefore, in this work, the centrifugal airfoil performance has been studied ...
Analysis Of The Overturning Of Heavy Vehicles In The “The Adioses” Curve Of The Highway Pamplona-Cúcuta

Moreno Contreras, Gonzalo Guillermo; Suarez C., Albert M.; PEÑA AVENDAÑO, IVAN CESAR; Moreno Gamboa, Faustino; Aperador Chaparro, William Arnulfo (Pakistan, 2021-09)

Over time, it has been observed that accidents due to vehicle overturning in the “The Adioses” curve of the Pamplona - Cúcuta road are a fairly frequent problem due to several factors such as: high speeds, absence of ...
Performance, Emission, and Economic Perspectives of a Diesel Engine Fueled with a Mixture of Hydroxy Gas and Biodiesel from Waste Palm Cooking Oil

Pardo García, Carlos Eduardo; PABON LEON, JHON ANTUNY; FONSECA VIGOYA, MARLEN DEL SOCORRO (International Review of Mechanical EngineeringItalia, 2021)

This investigation experimentally examines the influence of hydroxy gas fumigation in a diesel engine fueled with a biodiesel blend derived from waste palm cooking oil (B10). For the experimental tests, a fixed rotation ...
Evaluation of Performance Parameters and Emissions of a Diesel Engine Fueled with Preheated Palm Oil Mill Effluent Biodiesel Blends

Pardo García, Carlos Eduardo; PABON LEON, JHON ANTUNY; FONSECA VIGOYA, MARLEN DEL SOCORRO (International Review of Mechanical EngineeringItalia, 2021)

The current research analyzes the effect of fuel preheating on performance parameters and emission characteristics in a stationary diesel engine fuelled with palm oil mill effluent biodiesel blends. The investigation has ...
Evaluation of Energy Losses in Auxiliary Systems and Mechanisms Subject to Friction in a Stationary Diesel Engine

Pardo García, Carlos Eduardo; PABON LEON, JHON ANTUNY; FONSECA VIGOYA, MARLEN DEL SOCORRO (International Review of Mechanical EngineeringItalia, 2021)

This research has developed a methodology to estimate energy losses associated with auxiliary systems and mechanisms subject to friction in a stationary diesel engine. The study methodology is based on mathematical models ...
Analysis of the Tribological and Dynamic Characteristics of the Piston Compression Ring Under Different Engine Operating Conditions

Pardo García, Carlos Eduardo; PABON LEON, JHON ANTUNY; FONSECA VIGOYA, MARLEN DEL SOCORRO (International Review of Mechanical EngineeringItalia, 2021)

In this investigation, a study of the tribological and dynamic characteristics present in the compression ring is executed for different engine conditions. A series of numerical simulations has been carried out using the ...
IV international seminar on pedagogical practice (IV ISPP)

Prada-Nuñez, R; Torres-Ramírez, J E; Hernández-Suárez, C A; Gamboa-Suarez, A A; V-Niño, E D (Gamboa-Suarez A.A., 2021-08-27)

In the process of teaching and training students and new professionals, constructive actions and didactic spaces must be open where the teacher encourages the integral growth of their students, strengthening different ...
Study of the detonation wave in a rotating detonation combustor using hydrogen and mixtures ethylene-acetylene

Pardo García, Carlos Eduardo; PABON LEON, JHON ANTUNY; FONSECA VIGOYA, MARLEN DEL SOCORRO (International Review of Aerospace EngineeringItalia, 2021-04)

In this study, a comparison between the use of hydrogen and a mixture of ethylene-hydrogen-acetylene as fuels is made in order to evaluate the characteristics of the detonation wave in a rotating detonation combustor. For ...
Development of a virtual bench for the analysis of the physical processes of internal combustion engines

Rojas Suárez, J P; Pabón León, J A; Orjuela Abril, M S (2021-08-27)

Currently, internal combustion engines face the challenge of reducing fuel consumption and reducing polluting emissions due to their significant impact on the environment. Therefore, it is necessary to use tools that allow ...
Physics learning based on the use of concept maps

Pabón-Galán, C A; Hernández-Suarez, C A; Paz-Montes, L S (2021-11-18)

Concept maps are graphic learning tools that allow teachers and students to organize, represent knowledge, and visualize the relationships between concepts to promote understanding of physics. This study describes an ...
Numerical study of the physical processes of gas leakage in the compression ring in diesel engines

Pabón León, J A; Rojas Suárez, J P; Orjuela Abril, M S (2021-09-03)

In this research, the construction of a numerical model is proposed for the analysis of the friction processes and the thickness of the lubrication film present in the compression ring of internal combustion engines. The ...
Analysis of the application of physics in the design and construction of architectural projects. The Eiffel Tower

González-Almeyda, J.D.; Ayala-Garcia, E.T.; Prada-Nuñez, R. (2021-09-02)

This article studied the impact and application of physical concepts in the design and construction of the Eiffel Tower in Paris, an architectural reference that implemented physical concepts in its structural design. A ...
Attitudes towards physics. A study with high school students from the Colombian context

Hernánez-Suarez, C A; Gamboa-Suárez, A A; Suarez, O J (2021-09-03)

Science education should promote the development of competent students in science and develop their interest in science; however, although the role and relevance of science within society is evident; the interest towards ...
Study of the Kinematics and Dynamics of the Ring Pack of a Diesel Engine by Means of the Construction of CFD Model in Conjunction with Mathematical Models

Orozco Lozano, Wilman; Fonseca-Vigoya, Marlen Del Socorro; Pabón-León, Jhon (2021-11-28)

The present research aims to analyze the kinematic and dynamic behavior of the piston ring package. The development of the research was carried out through the development of numerical simulation by means of CFD. The ...
Soil Organic Carbon Dynamics in Two Rice Cultivation Systems Compared to an Agroforestry Cultivation System

Valenzuela-Balcázar, Ibonne Geaneth; Visconti-Moreno, Efraín Francisco; Faz, Ángel; Acosta, José A. (2021-12-23)

After changes in tillage on croplands, it is necessary to assess the effects on soil organic carbon (SOC) dynamics in order to identify if soil is a sink or emitter of carbon to the atmosphere. This study was conducted in ...
SYNERGISTIC CORROSION-WEAR EFFECT IN AUSTENITIC POWDER METALLURGICAL STEEL WITH DIFFERENT TITANIUM ADDITIONS

Aperador, w; Bautista-Ruiz, J; Caicedo, J. (2022-01-01)

To ascertain the influence of titanium percentage in 316L austenitic steel, titanium percentages varied from 0.5 to 2% aggregated to 316L steel. The powder metallurgy method was used. The powdered material was pressed at ...
A Simulation Analysis of a Microalgal-Production Plant for the Transformation of Inland-Fisheries Wastewater in Sustainable Feed

García-Martínez, Janet B; Contreras-Ropero, Jefferson E; Urbina-Suarez, Néstor A.; López-Barrera, Germán L.; Barajas-Solano, Andrés F; Kafarov, Viatcheslav; Barajas-Ferreira, Crisóstomo; Ibarra-Mojica, Diana M.; Zuorro, Antonio (2022-01-16)

The present research evaluates the simulation of a system for transforming inland-fisheries wastewater into sustainable fish feed using Designer® software. The data required were obtained from the experimental cultivation ...
Prospects for using wastewater from a farm for algae cultivation: The case of Eastern Colombia

Urbina-Suarez, Nestor Andres; Barajas-Solano, Andres Fernando; Garcia-Martinez, Janet Bibiana; Lopez-Barrera, German Luciano; González-Delgado, Angel Dario (2021-05-24)

: In recent years, the technical and economic feasibility of using microalgae and cyanobacteria has been explored for the removal and exploitation of domestic, agricultural and industrial residual effluents with high C, ...

Envíos recientes

Experimental study of emissions in single-cylinder diesel engine operating with diesel-biodiesel blends of palm oil-sunflower oil and ethanol
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Vergel Ortega, Mawency | 2021-08

This study investigates an alternative fuel methodology for diesel engines that focus on the influence of ethanol as an additive agent in biodiesel blends derived from the industrial liquid waste of palm oil and sunflower oil residues. Specifically, the study addresses relevant aspects of the combustion performance and emissions characteristics in a single-cylinder diesel engine. For the experimental development, four different fuels were tested: commercial diesel, a blend of biodiesel formed from the residual material of palm oil and sunflower oil (PB3SB2), two blends with an addition of 2%, and 4% ethanol in the biodiesel produced (PB3SB2E2 and PB3SB2E4). The engine operated under nine different operation modes following international testing methodologies. Results indicated that incorporating ethanol in the PB3SB2 biodiesel blend improves thermal efficiency by 0.8%. Increasing the ethanol mixing ratio to 4% provides a further efficiency improvement of up to 1.2%. The emissions analysis showed that the addition of ethanol below 4% in the biodiesel blend facilitates the minimization of pollutant levels of CO, CO2, NOx, HC, and smoke opacity compared to the biodiesel formed by the two residual oils (PB3SB2). Overall, ethanol incorporation reduced emissions levels between 7.5 and 13.87% compared to PB3SB2. In conclusion, integrating biodiesel and ethanol as additive agent emerges as a promising alternative to promote a reliable and sustainable operation in diesel engines.

LEER
Prefase V International Meeting of Mathematical Education
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Vergel Ortega, Mawency | 2021-05-22

The objective of the V International Meeting on Mathematics Education (V IMME) is to create and maintain a space that privileges and promotes the culture of mathematics, reflection and discussion on the education and application of mathematics, statistics, its history, evolution and didactics, and its interrelation with the sciences. At the meeting, researchers, scientists, and mathematics teachers socialize the results of research, consolidate networks for the exchange of successful experiences, to strengthen mathematics education at different educational levels, promote innovation and encourage the creation of policies, models, educational strategies, tools, and techniques in various areas of mathematics. They also promote innovation and encourage the creation of policies, models, educational strategies, tools and techniques in different areas of knowledge, and foster students' interest in research. This academic space has been maintained, so in the first semester of 2017 the First International Mathematics Education Meeting was held, with the presence and participation of teachers, students and professionals from different university, basic and secondary education institutions. During the Summit, researchers carry out activities such as, master conferences, short lectures. In this year 2021, the thematic areas in this meeting were: Mathematics education for science and engineering, Physics-mathematics applied to medicine, Modeling, simulation, and diagnostics, Applied physics-mathematics, Mathematics and statistics, Application of physiochemistry, Computer science, Origami

LEER
Experimental and CFD Study of a Centrifugal Fan Performance Under ANSI/AMCA Standard
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Rojas Suárez, Jhan Piero | 2021

Centrifugal fans are widely employed for several technical applications in science and engineering due to their easy employment and practical use. Therefore, in this work, the centrifugal airfoil performance has been studied with experimental and computational fluid dynamics techniques in order to improve their energy efficiency influenced by the rotor-stator interaction. In this sense, this research proposes a study of the main components' aerodynamic performance in order to determine the optimal operating conditions for different geometries of the impeller blades. In order to validate the simulation results, an experimental study has been performed to configure the design of experiments with the data acquisition of velocity and pressure values of the air mass flow under different conditions in the test bench configured with the ANSI/AMCA 210-07 standard. The experimental procedure has been performed with 2500 rpm, like a constant value of the centrifugal fan's angular velocity. The experimentally acquired data have allowed validation and the definition of each treatment's response to establish a linear regression model in order to predict centrifugal fan performance under different working conditions. 5.4 kPa has been determined as the high static pressure value for different impeller blade configurations conformed by the blades' angle, number, and length features.

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Analysis Of The Overturning Of Heavy Vehicles In The “The Adioses” Curve Of The Highway Pamplona-Cúcuta
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Moreno Contreras, Gonzalo Guillermo | 2021-09

Over time, it has been observed that accidents due to vehicle overturning in the “The Adioses” curve of the Pamplona - Cúcuta road are a fairly frequent problem due to several factors such as: high speeds, absence of traffic signs, driver maneuvers, among others. This is why this section of the road has been classified as a critical accident point. The vehicles that are most affected are heavy vehicles (truck tractors), which due to their large size have a high gravity center, which hinders their stability compared to other vehicles. Another important aspect that it is taken into account is the characteristics of the road that can modify the load distribution in the vehicle. All these aspects are evaluated through a case study which allows calculating the stability factor for a particular heavy vehicle and calculating the safe traffic speed for this vehicle in the specified sector.

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Performance, Emission, and Economic Perspectives of a Diesel Engine Fueled with a Mixture of Hydroxy Gas and Biodiesel from Waste Palm Cooking Oil
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Pardo García, Carlos Eduardo | 2021

This investigation experimentally examines the influence of hydroxy gas fumigation in a diesel engine fueled with a biodiesel blend derived from waste palm cooking oil (B10). For the experimental tests, a fixed rotation speed of 2000 rpm and a load condition of 50%, 75%, and 100% have been established. Hydroxy gas (HHO) has been added through the engine's air intake system at a flow of 0.5 lpm, 0.75 lpm, and 1 lpm. Results have demonstrated the positive effect of HHO fumigation on the combustion performance of the B10 blend. Moreover, a reduction of 4.3% in the BSFC and a 2.64% increase in peak pressure in B10 due to the presence of HHO have been observed. On the other hand, a decrease of 8.7%, 9.9%, and 22.8% in CO2, HC, and smoke opacity emissions has been evidenced with the addition of HHO in B10. B10 implementation has promoted NOx emission escalation. However, this increase has been only 1.23% compared to pure diesel. In conclusion, HHO enrichment favors combustion performance and emissions minimization, which represents a significant opportunity to mitigate the negative effect of the lower calorific power of these types of fuels.

LEER
Evaluation of Performance Parameters and Emissions of a Diesel Engine Fueled with Preheated Palm Oil Mill Effluent Biodiesel Blends
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Pardo García, Carlos Eduardo | 2021

The current research analyzes the effect of fuel preheating on performance parameters and emission characteristics in a stationary diesel engine fuelled with palm oil mill effluent biodiesel blends. The investigation has been carried out on an experimental test bench under four-engine load conditions. The fuel injection temperature range is set between 35-75 °C. From the results obtained, it has been possible to demonstrate that the preheating process allows the reduction of fuel consumption and an increase in the efficiency of the engine powered with POME 5 and POME 10 blends. The preheating process has the potential to reduce by 14 % BSFC and increase by 17% the BTE of the engine. Additionally, the results have showed a reduction potential of 17.2%, 16.5%, and 15.6% in CO2, HC, and smoke opacity emissions when preheating processes are used in POME biodiesel blends. In general, this type of strategy is a promising solution to incentivize the use of biodiesel blends from palm oil mill effluent.

LEER
Evaluation of Energy Losses in Auxiliary Systems and Mechanisms Subject to Friction in a Stationary Diesel Engine
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Pardo García, Carlos Eduardo | 2021

This research has developed a methodology to estimate energy losses associated with auxiliary systems and mechanisms subject to friction in a stationary diesel engine. The study methodology is based on mathematical models used to calculate engine friction forces and power losses. The analysis involves the cooling, the lubrication, the fuel injection system, and the engine's valve train, bearings, and piston mechanism. A stationary diesel engine with four load conditions and three rotational speed conditions has been taken as a reference for the study. The analysis of the results has showed that fuel injection is the auxiliary system with the highest energy consumption. In general, the cooling system, the lubrication, and the injection represent loss energy equivalent to 0.3%, 0.5%, and 0.9% of the chemical energy of the fuel. The interaction between the cylinder liner and the piston skirt is the main source of energy loss associated with friction processes. For valve train mechanisms, bearings and pistons it has been evidenced that these represent 1.25%, 1.91%, and 5.26% of the chemical energy of the fuel. In general, the methodology proposed in this research is a tool that allows diagnosing energy losses in auxiliary systems and engine mechanisms, which is useful for evaluating future strategies focused on energy improvement.

LEER
Analysis of the Tribological and Dynamic Characteristics of the Piston Compression Ring Under Different Engine Operating Conditions
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Pardo García, Carlos Eduardo | 2021

In this investigation, a study of the tribological and dynamic characteristics present in the compression ring is executed for different engine conditions. A series of numerical simulations has been carried out using the OpenFOAM software for the study. The simulation conditions have been based on the parameters measured on a diesel engine test bench. Different ranges of rotation speed, load, and lubrication oil temperature have been established for the analysis. The results show that the parameters of rotation speed and engine load significantly influence the tribological and dynamic conditions of the piston compression ring. An increase of 425 rpm and 136 Nm in the rotational speed and load of the engine causes an increase of 13% and 34% in the power loss due to friction. The Top Dead Center and the Bottom Dead Center are the locations most prone to experience critical wear and tear. Increasing the lubricating oil temperature increases the maximum friction force by 9%. In general, the proposed methodology allows for establishing a direct relationship between the operating conditions and the tribological characteristics in the compression ring that directly affect the efficiency and useful life of the engine.

LEER
IV international seminar on pedagogical practice (IV ISPP)
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Prada-Nuñez, R | 2021-08-27

In the process of teaching and training students and new professionals, constructive actions and didactic spaces must be open where the teacher encourages the integral growth of their students, strengthening different technical/academic aspects and personal skills. With a good orientation and implementation of appropriate pedagogical practices, the teacher will have the ability to teach and create spaces to socialize, discuss and reflect about experiences that generate, not only the construction of new knowledge, but also the strengthening of principles and qualities in students, such as responsibility, honesty, equity, respect and the ability to reason to solve problems and conflicts. All this promotes the formation of human capital capable of confronting and solving different aspects and challenges that may be encountered in their training process and professional development. The present proceedings are part of the contributions of the participants in the IV International Seminar on Pedagogical Practice (IV ISPP) which was held from 26 to 27 August 2021, in the city of San José de Cúcuta, Colombia; congress was organized by the "Facultad de Educación, Artes y Humanidades" of the Universidad Francisco de Paula Santander, San José de Cúcuta, Colombia The main purpose of the IV ISPP was to create a space for training and academic and scientific cooperation for the construction, exchange, and development of research that aimed at the consolidation of innovation processes in education and pedagogical practices. This edition of the IV ISPP has emphasized the research, innovations, and reflections on didactics of natural sciences (mathematics, physics, chemistry, and biology) and its applications at both educational and scientific. The IV ISPP was attended by researchers, teachers of the basic, middle, and higher education, graduate and undergraduate students from Colombia, Argentina, Mexico, Chile, El Salvador, and Spain, who shared their contributions in the fields of teaching and applications of natural sciences (physics, mathematics, chemistry, biology, physics-mathematics, physical-chemistry, biophysics, Statistics, and education). On behalf of the organizing committee of the IV ISPP, we are extremely thankful to all authors and participants for providing their valuable contributions to this Proceedings volume as well as the reviewers for their constructive recommendations and criticism aiding to improve the presented articles. Likewise, we like to thank the Universidad Francisco de Paula Santander (UFPS), and the Foundation of Researchers in Materials Science and Technology (FORISTOM), and Red Iberoamericana de Pedagogia (REDIPE), for all the support technical and logistical received. Finally, the editor hopes that those interested in the area of pedagogical practice and didactics in natural sciences can enjoy this reading, of the volume of the Journal of Physics: Conference Series (JPCS), which reflects a wide variety of current issues.

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Study of the detonation wave in a rotating detonation combustor using hydrogen and mixtures ethylene-acetylene
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Pardo García, Carlos Eduardo | 2021-04

In this study, a comparison between the use of hydrogen and a mixture of ethylene-hydrogen-acetylene as fuels is made in order to evaluate the characteristics of the detonation wave in a rotating detonation combustor. For the experimental development, an annular combustor, which has been connected to a supply of air, fuel, and hydrogen, has been used. The air and the type of fuel have been injected separately into the combustion chamber. The measurement of key parameters involves the use of ionization probes and pressure sensors, which have been located in the body of the combustion chamber. The results obtained indicate that hydrogen can reach an average pressure in the detonation wave 37% higher compared to the fuel mixture (ethylene-hydrogen-acetylene). For hydrogen, the equivalency ratio range is 38% higher compared to the fuel mixture. Therefore, the use of fuel mixtures is in a more limited operating range. The study of the detonation wave velocity indicates that the mixture of fuel and hydrogen can reach 68% and 93% of its ideal wave detonation velocity. However, in terms of height, both types of fuels reach a wave height of 30 mm. In general, hydrogen has characteristics that are more favourable in its detonation wave.

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Development of a virtual bench for the analysis of the physical processes of internal combustion engines
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Rojas Suárez, J P | 2021-08-27

Currently, internal combustion engines face the challenge of reducing fuel consumption and reducing polluting emissions due to their significant impact on the environment. Therefore, it is necessary to use tools that allow us to evaluate the operating characteristics of this type of thermal machines. In the present investigation, the development of a virtual bench was proposed for the analysis of the behavior and performance characteristics of an internal combustion engine for use as a learning tool in higher education students. From the results obtained, it could be demonstrated that the pressure curves of the combustion chamber and the rate of heat release obtained by means of the virtual bench presented a high concordance with the experimental records. The maximum deviation obtained was 5% and 15% for the pressure curve and the heat release rate. Comparing the performance parameters of the brake specific fuel consumption of the engine and energy efficiency, a maximum deviation of 2.96% was shown compared to the real engine. In general, the virtual development bank can describe the behavior of the engine, allowing the characterization of physical phenomena, as well as evaluating the effect of auxiliary technologies such as turbo-compression systems.

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Physics learning based on the use of concept maps
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Pabón-Galán, C A | 2021-11-18

Concept maps are graphic learning tools that allow teachers and students to organize, represent knowledge, and visualize the relationships between concepts to promote understanding of physics. This study describes an innovative experience based on the development of concept maps with the aim of analyzing the perception of students in a teacher training program in natural sciences and environmental education at a public university in Colombia. The research subjects were 24 students studying basic physics who used concept maps for learning, and the data were analyzed quantitatively using a non-experimental design. The results show that the trainee teachers learned to elaborate concept maps, valuing very positively their educational applications to improve learning. It is concluded that concept mapping can be used to increase students' understanding and motivation which should help to improve their academic performance.

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Numerical study of the physical processes of gas leakage in the compression ring in diesel engines
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Pabón León, J A | 2021-09-03

In this research, the construction of a numerical model is proposed for the analysis of the friction processes and the thickness of the lubrication film present in the compression ring of internal combustion engines. The model is built using MATLAB software, and three load conditions are used as reference (2 Nm, 4 Nm, and 6 Nm) with a rotation speed of 3600 rpm, which correspond to a stationary single-cylinder diesel engine. Comparison between model estimates and experimental results show that the development model could predict the actual engine conditions. The deviation between the numerical model and the experimental data was 17%. It was shown that the increase in engine load causes a 16% increase in the friction force of the compression ring, which implies a 50% increase in power loss due to friction processes. In general, the model developed allows the analysis of the friction processes in the compression ring and its effect on the lubrication film, considering the leakage of the combustion gases. In this way, the construction of a more complex mathematical model is achieved, which allows improving the precision in the analyzes related to the interaction between the compression ring and the cylinder liner.

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Analysis of the application of physics in the design and construction of architectural projects. The Eiffel Tower
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González-Almeyda, J.D. | 2021-09-02

This article studied the impact and application of physical concepts in the design and construction of the Eiffel Tower in Paris, an architectural reference that implemented physical concepts in its structural design. A documentary methodological framework was used to establish the importance of the Eiffel Tower in the universal exposition of Paris in 1989 and, to carry out the structural analysis of the work; a quantitative-descriptive approach was used for the recognition of the basic concepts of physics from architecture according to gender, through a survey as a research instrument developed under non-probability and convenience sampling, which was applied to students of Architecture of the Universidad Francisco de Paula Santander, Colombia, in order to determine the knowledge of basic physics by students. The results of this research showed that the Eiffel Tower represents a milestone in architecture where physical concepts such as tension, compression, traction, aerodynamics, and torque were applied. Finally, it was evidenced that the students who participated in this study recognize the importance of applying the basic concepts of physics in architecture; fact by which it is recommended to encourage the study of physics, to strengthen the technological component of Architecture.

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Attitudes towards physics. A study with high school students from the Colombian context
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Hernánez-Suarez, C A | 2021-09-03

Science education should promote the development of competent students in science and develop their interest in science; however, although the role and relevance of science within society is evident; the interest towards it is not conscious, being the negative attitudes of the students the main problem in the teaching of physics, which translates into a deficient knowledge and lack of scientific vocation. This report aims to diagnose the attitudes of students in high school physics courses. The study was developed through a non-experimental, descriptive research design, obtained from the application of a Likert scale that evaluates attitudes towards physics, adapted and validated to the context of students in an educational institution in Colombia. The results indicate that the attitudes of the students are slightly favorable, which is an empirical precedent to continue with the studies on attitudes towards physic. This should be considered to enhance the learning processes in these students, especially for those who have their first approach to physical concepts and give importance to attitudes when teaching.

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Study of the Kinematics and Dynamics of the Ring Pack of a Diesel Engine by Means of the Construction of CFD Model in Conjunction with Mathematical Models
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Orozco Lozano, Wilman | 2021-11-28

The present research aims to analyze the kinematic and dynamic behavior of the piston ring package. The development of the research was carried out through the development of numerical simulation by means of CFD. The analysis involves the three piston rings for the development of simulations that are closer to the real conditions of the engine since most of the investigations tend to focus on the study of the compression ring only. The simulation was reinforced by the incorporation of mathematical models, which allow determining the piston kinematics, the lubrication properties as a function of temperature, contact friction, and gas leakage. For the simulation, the CAD of the piston and the connecting rod—crankshaft mechanism was carried out, taking as a reference the geometry of a diesel engine. From the results obtained, it was possible to show that the first ring exhibits considerably greater radial and axial movement compared to the second and third piston rings. Additionally, it was shown that the first and second rings tend to maintain a negative tilt angle throughout the combustion cycle, which facilitates the advancement of the combustion gases over the piston grooves. Therefore, it is necessary to use strategies so that these rings tend to maintain a positive inclination. The analysis of the pressure conditions in the second ring are 150% and 480% higher compared to the conditions present in the third ring. Due to the above, it is necessary to focus efforts on the design of the profile of this ring. The study of energy losses showed that the combination of leakage gases and friction are responsible for a mechanical loss between 6–16%. In general, the development of the proposed methodology is a novel tool for the joint analysis of the kinematic characteristics, pressure conditions, and energy losses. In this way, integrated analysis of changes caused by piston ring designs is possible.

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Soil Organic Carbon Dynamics in Two Rice Cultivation Systems Compared to an Agroforestry Cultivation System
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Valenzuela-Balcázar, Ibonne Geaneth | 2021-12-23

After changes in tillage on croplands, it is necessary to assess the effects on soil organic carbon (SOC) dynamics in order to identify if soil is a sink or emitter of carbon to the atmosphere. This study was conducted in two plots of rice cultivation, where tillage and water management changes occurred. A third plot of native forest with Cacao trees was used as reference soil (agroforestry). For SOC balance estimation, measurement of organic carbon (OC) inputs was determined from necromass, roots, microbial biomass, and urea applications. CO2 and CH4 emissions were also measured. Results showed that the change in the use of irrigation and tillage in rice cultivation did not cause significant differences in OC inputs to soil or in outputs due to carbon emissions. Further-more, it was found that both irrigation and tillage management systems in rice cultivation com-pared with agroforestry were management systems with a negative difference between OC inputs and outputs due to CO2 emissions associated with intense stimulation of crop root respiration and microbial activity. The comparison of SOC dynamics between the agroforestry system and rice cultivation systems showed that an agroforestry system is a carbon sink with a positive OC dynamic.

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SYNERGISTIC CORROSION-WEAR EFFECT IN AUSTENITIC POWDER METALLURGICAL STEEL WITH DIFFERENT TITANIUM ADDITIONS
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Aperador, w | 2022-01-01

To ascertain the influence of titanium percentage in 316L austenitic steel, titanium percentages varied from 0.5 to 2% aggregated to 316L steel. The powder metallurgy method was used. The powdered material was pressed at 800 MPa and then sintered at 1300°C. The X-ray diffraction (XRD) technique was used to characterize the identification of the phases after the processed mixtures. Wear and tribowear properties were determined by pin on disc tests. Electrochemical polarization curves were used to study corrosion. According to the results of the samples, the corrosion resistance of titanium increased to a percentage of 1.5% due to the formation of the phases generated by the mixture. However, it was determined that the most appropriate percentage is 2%, due to the synergistic mode specifically for wear and corrosion resistance, the mechanism is the most adequate.

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A Simulation Analysis of a Microalgal-Production Plant for the Transformation of Inland-Fisheries Wastewater in Sustainable Feed
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García-Martínez, Janet B | 2022-01-16

The present research evaluates the simulation of a system for transforming inland-fisheries wastewater into sustainable fish feed using Designer® software. The data required were obtained from the experimental cultivation of Chlorella sp. in wastewater supplemented with N and P. According to the results, it is possible to produce up to 11,875 kg/year (31.3 kg/d) with a production cost of up to 18 (USD/kg) for dry biomass and 0.19 (USD/bottle) for concentrated biomass. Similarly, it was possible to establish the kinetics of growth of substrate-dependent biomass with a maximum production of 1.25 g/L after 15 days and 98% removal of available N coupled with 20% of P. It is essential to note the final production efficiency may vary depending on uncontrollable variables such as climate and quality of wastewater, among others.

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Prospects for using wastewater from a farm for algae cultivation: The case of Eastern Colombia
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Urbina-Suarez, Nestor Andres | 2021-05-24

: In recent years, the technical and economic feasibility of using microalgae and cyanobacteria has been explored for the removal and exploitation of domestic, agricultural and industrial residual effluents with high C, N and P compounds content. To contribute to the understanding of the process and its technical viability for microalgae growth, the article discusses monitoring, flow determination, and physicochemical characteristics of two types of effluents generated in an experimental farm located in the east of Colombia, before (R1) and after biological treatment (R2). In general, the results showed the reduction of different parameters, such as total dissolved solids (TDS), hardness, salinity and phosphates after treatment with activated sludge. However, the conductivity value obtained in R1 and R2 showed the presence of a pollutant load. These findings can be attributed to the highest concentration of fats and oils in the water during early hours of the day. Finally, although the concentration of nitrates increased from 46.63 to 225.21 mg∙dm–3 and phosphate decreased slightly from 9.65 to 6.21 mg∙dm–3, no inhibition was generated in the microalgae, as evidenced in the growth of the microalgal biomass in effluents after nitrate and phosphate removal above 80%.

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