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Infraestructura Vial - GINFRAVIAL

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Study of performance and emissions in diesel engines operating with biodiesel from soybean oil and water emulsions

Orjuela Abril, Martha Sofia | 2021-01-01

Este estudio evalúa la influencia en el proceso de combustión, consumo de combustible y emisiones contaminantes en un motor diesel, que opera con biodiesel a partir de aceite de soja y emulsiones de agua con porcentajes de 4% y 8%. Para este estudio, se utiliza un motor diesel estacionario que opera en cuatro condiciones de par diferentes y una velocidad de rotación fija de 3400 rpm. Los combustibles de prueba son diésel, biodiésel de aceite de soja y emulsiones de agua SB4W y SB8W. Los resultados indican que SB4W y SB8W provocan una reducción del 6% en el poder calorífico y un aumento del 18% y del 1% en la viscosidad y densidad. Sin embargo, la presencia de agua en el biodiésel puede ayudar a reducir el BSFC del motor en un 8%. El SB4W y SB8W permiten una reducción del 23% en las emisiones de NOx. Con el uso de combustible SB4W se obtiene una reducción del 16%, 29% y 14% en CO, HC y opacidad del humo en comparación con el biodiésel de aceite de soja. Se recomienda la inclusión máxima de 8% de agua en el biodiesel de aceite de soja ya que un porcentaje mayor puede provocar la presencia de combustiones incompletas.

Development of an electro-pneumatic system for the practical training of pneumatic processes in the university environment

Rojas Suárez, Jhan Piero | 2021-06-11

This article describes the implementation of an electro-pneumatic test bench, which allows the availability of a physical environment to promote learning. The aim of the paper is to create a tool that enables practical training and research of pneumatic processes for university students in the field of engineering. The control and automation system of the test bench is made up of wired logic panels, timers, and programmable logic controllers, which are integrated into a control board configured at 24 V (direct current) to guarantee safety. Additionally, ergonomic principles were considered for the construction of the electro-pneumatic bench, thus favoring the accessibility and safety of the users. Based on national and international regulations, working pressure of 9 bar and an approximate pressure drop of 0.07 bar were defined. The construction of the test bench is considered an educational strategy to facilitate and accelerate the learning process of the students. Additionally, the development of the electro-pneumatic bench allowed the dynamic characterization of double-acting actuators by integrating experimental data and numerical models. This allowed the detailed analysis of the displacement, velocity, and acceleration variables in this type of actuator, which contributes to the physical study of pneumatic systems.

Acoustic emissions in the valuation of the combustion chamber pressure of an engine

Rojas Suárez, J P | 2021-08-26

Internal combustion engines demand advanced monitoring methodologies to promote efficient operation; particularly, the combustion pressure plays a central role in the overall performance, which promotes the utilization of transducers that hinders. Therefore, the present study introduces an acoustic emission methodology that serves for indirect combustion pressure measurements. Accordingly, the compound methodology integrates the Hilbert transform and the complex cepstrum using neural networks to accomplish pressure signal reconstruction. Results demonstrated that the proposed methodology featured robust performance while estimating pressure signals as it mitigates the combined noise effect produced by variations in engine speed, engine load, and fuel type. Moreover, the reconstructed signal facilitated the determination of key performance parameters such as peak pressure, pressure timing, and effective mean pressure. Relative error amounted to less than 10%, which ratified the robustness of the indirect pressure measurements. In conclusion, acoustic signal techniques represent an adequate approach to estimate the combustion pressure at variable engine conditions.

2D Simulation of Two-Phase Flow for Water Jet Cutting Processes with OpenFOAM

Florez, Eder | 2021

Cold cutting processes are characterized to perform the kinetic energy needed to cut hard materials with little mechanical effort by means of the ultra-high flow pressure pumps, which produce water jets with a flow pressure value of around 90 ksi. These manufacturing processes may be studied considering the fluid mechanics' principles that describe the transport phenomena for inviscid, continuous, and incompressible laminar flows in order to obtain theoretical results approximated to the process conditions. In this sense, the numerical modeling techniques applied in the analysis of water jet cutting processes define an efficient solution of the processes due to the physical analysis of the partial differential equations, which quantify the abrasive flow particles into the system. Taking into account the above, this research proposes a numerical analysis of the physical phenomena through the two-phase flow simulation in steady state with OpenFOAM. Abrasive and liquid phases are quantified to study the turbulent values, which describe the water jet behavior under different working conditions. A 2D model has been computed and discretized, considering the nozzle features in order to visualize and predict the abrasive mixture and flow rejected by using a low computational effort. Therefore, this numerical approach has been validated with a mesh independency analysis developed to verify the relation between the numerical data and the finite number of nodes computed in order to discretize a computational domain and to solve analytically the system proposed until reaching a high approximation between the model and the experimental values obtained during the cutting process by means of abrasive flows.

Hydraulic modeling of combined sewers overflow integrating the results of the swmm and CFX models

Pulgarín, D A | 2021-01-19

This study proposes a methodology for the calibration of combined sewer overflow (CSO), incorporating the results of the three-dimensional ANSYS CFX model in the SWMM onedimensional model. The procedure consists of constructing calibration curves in ANSYS CFX that relate the input flow to the CSO with the overflow, to then incorporate them into the SWMM model. The results obtained show that the behavior of the flow over the crest of the overflow weir varies in space and time. Therefore, the flow of entry to the CSO and the flow of excesses maintain a non-linear relationship, contrary to the results obtained in the onedimensional model. However, the uncertainty associated with the idealization of flow methodologies in one dimension is reduced under the SWMM model with kinematic wave conditions and simulating CSO from curves obtained in ANSYS CFX. The result obtained facilitates the calibration of combined sewer networks for permanent or non-permanent flow conditions, by means of the construction of curves in a three-dimensional model, especially when the information collected in situ is limited.

Renewable Energies Resources Evaluation using a Geographic Information Systems in the Colombian Caribbean Region

Romero-Garcia , Gonzalo | 2021-11-05

This manuscript presents an integral evaluation of the use of wind and solar resources in the Colombian Caribbean region. For the use of solar and wind energy sources, spatial restrictions according to topography, natural parks, water reserves, indigenous and sacred reserves were taken into account. In addition, studies of the energy potential of wind and solar radiation were carried out through geostatistical analysis of different points in meteorological stations located in the region. Finally, areas with wind and solar potential were determined using the Geographic Information System for Renewable Energies (SIGER). The results show that the department of Guajira has the highest values of solar brightness (229-240 Month day), while the departments of Valledupar, Cesar, and part of Magdalena decrease in the range of 229 to 207 Month day. In terms of solar radiation, the departments of Guajira and Atlántico showed global solar radiation values of up to 6,015 W/m2. The departments of Cesar, Magdalena, and part of Bolivar showed values close to 5,259 W/m2; while Sucre, and Cordoba showed low solar radiation values of 4,502 W/m2. It is concluded that the departments of Atlántico and Guajira are excellent candidates for solar and wind energy projects due to their characteristics. The results of this manuscript are a fundamental basis for future technical-economic feasibility studies of renewable energy in the Colombian Caribbean region. In addition, it allows the elaboration of energy policies that encourage the execution of this type of study at a real level.

Operational Failure Detection Applied to Heat Exchange Systems Using State Observer Method

Rojas Suárez, Jhan Piero | 2021

The role of computational modeling is becoming predominant in the exploration and evaluation of new technologies. Numerical simulations have solved the most complex phenomena immersed in thermal sciences by the implementation of sophisticated mathematical algorithms. This study incorporates a stationary thermodynamic model in order to evaluate the main operational parameters and the overall performance of heat exchange systems based on energy and exergy viewpoints while implementing unknown inputs. Moreover, the study introduces a UIO state observer technology in order to facilitate the early prediction of failure events in heat exchange systems using a detect, isolate and identify (FDI) methodology. Therefore, the proposed model has induced different fault conditions in order to examine the overall performance while integrating error state of signals criteria from the relative difference between the real and modeled estimates. The outcomes have demonstrated a good agreement for the estimated values of the mathematical algorithm considering the imminent presence of disturbance and interference that promotes modeling error. Finally, the results have outlined that the estimations of real operation conditions are not affected by the unknown inputs.

Experimental and CFD Study of a Centrifugal Fan Performance Under ANSI/AMCA Standard

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.

Development of a virtual bench for the analysis of the physical processes of internal combustion engines

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.

Analysis of the influence of textured surfaces and lubrication conditions on the tribological performance between the compression ring and cylinder liner

Pardo García, Carlos Eduardo | 2021-05-06

The objective of the present investigation is to analyze the tribological performance between the union of the cylinder liner and the compression ring under the influence of surface texturing and different lubrication boundary conditions. The analysis is carried out by developing a numerical model, which involves hydrodynamic pressure, lubrication film thickness, textured surface, dynamic forces, and lubrication boundary conditions (starved lubrication and fully flooded lubrication). MATLAB® software (The MathWorks Inc., Natick, MA, USA) is used to solve the equations developed. The results show that the application of a textured surface on the cylinder liner allows obtaining a reduction of 20% and 5% in the asperity contact force and in the total friction force. Additionally, the textured surface allows for a 4% increase in MOFT. In this way, it is possible to reduce the power loss. The implementation of a boundary condition of fully flooded lubrication produces an overestimation in the total friction force due to the greater prominence of the lubrication film. Implementing a textured surface in the ring profile is an alternative way to reduce power loss. The results show that this alternative allows an 8% reduction in power loss.

Document details - A numerical model for the analysis of the bearings of a diesel engine subjected to conditions of wear and misalignment

Pardo García, Carlos Eduardo | 2021-04-09

In the present work, a numerical model is developed to investigate the influence of wear and misalignment on the bearings of a stationary diesel engine. The model implemented considers the effects of surface wear on the bearing, cavitation effects, and surface roughness. For the numerical analysis, changes in the surface roughness of σ = 0.75 µm, σ = 1 µm, and σ = 1.25 µm are defined, and changes in the bearing load of 50%, 75%, and 100%. The results demonstrated that increasing the surface roughness intensifies the bearing wear, which represents 18% and 140% of the bearing clearance for the roughness of σ = 1 µm and σ = 1.25 µm, respectively. Additionally, the surface roughness causes a considerable increase in the bearing wear rate. The results described a maximum wear rate of 20 µm/s. In general, increasing the bearing load by 25% doubles the hydrodynamic pressure conditions increases friction force by 33%, and reduces lubrication film thickness by 12%. The analysis of the angle of deflection, φx and φy, shows that the moment and the degree of misalignment tend to increase significantly with the increase in the magnitude of the angle φy. Negative angles of deflection, φx, produce a greater increase in the degree of misalignment and the moment. This implies a greater chance of contact with the bearing surface. In conclusion, the proposed methodology serves as a reliable tool to simultaneously evaluate key parameters on the tribological behavior of bearings that further extend their endurance and minimize wear damage.

An application of physics: simply supported bridges made of post-tensioned concrete and structural steel beam

Márquez Peñaranda, J F | 2022-01-06

Bridges represent an important application of physics capable of solving real transportation problems. Knowledge of convenience of different mechanical solutions when analyzing and designing bridge is needed. For these reasons, this work is focused on the study of convenience of using two types of bridges. Simply supported short-medium span bridges (30 m to 45 m) are usually excessively long when choosing reinforced concrete solutions and usually short for other types of structures such as cable-stayed or cantilever bridges. The suitability of simply supported bridges leads to the need of studying their cost benefit ratios. This work studies the cost benefit ratio for post-tensioned concrete beams and structural steel girders in simply supported straight bridges. Eight models built of type I sections were used in both cases to analyze the bridges using a software based on the stiffness method. Span of each bridge was set to 30 m, 35 m, 40 m, and 45 m. The convenience of each type of bridge was done comparing the total and the cost per linear meter of each solution (post-tensioned and structural steel). Comparison was done using material consumption, labor, and construction processes costs only. Also, allowable vertical displacement given by current bridge design standards was verified

Simulation study of phase change materials operating in thermoelectric devices

Orjuela Abril, Martha Sofia | 2021-06-04

In this paper, a computerized analysis is performed to evaluate the effect of phase change materials on the performance of thermoelectric generators. This study was conducted using commercial OpenFOAM software. Analyze changes in temperature, potential and efficiency due to phase change materials. The study evaluated a variety of geometric and operational conditions, such as changes in material height and heat flux. The results obtained indicate that the presence of phase change material allows a significant increase in the temperature difference between the surfaces. The temperature difference is increased by 35% with a height of 3.25 mm. The temperature difference increases the potential of the thermoelectric generator and increases the maximum output voltage by 21%. Overall, phase change materials have been shown to improve thermoelectric efficiency by 23%. For test conditions, the maximum efficiency is 4.77%. From this result, it can be concluded that the phase change material is a promising alternative for improving the low efficiency of thermoelectric generators due to their heat storage capacity.

Development of a numerical methodology for evaluating physical properties and technical specifications in thermoelectric devices

Prada Botia, Gaudy Carolina | 2021-06-04

Typically, the performance evaluation of thermoelectric devices is done using experimental methods and analytical models, which require detailed information on the thermoelectric properties of the materials that make up the thermoelectric devices. However, this type of information is generally not available. Due to this situation, the present investigation seeks to develop a numerical methodology to determine the performance of thermoelectric devices, using technical reference specifications that are normally provided by the manufacturer, such as maximum current, maximum voltage, maximum temperature difference, and efficiency. The numerical model is made up of a series of equations based on thermoelectric phenomena, which generates a contribution in the area of physics. The results obtained are validated through experimental comparisons and the technical data of the thermoelectric devices. The comparison between the different results shows a maximum error of 5%. Therefore, the developed methodology is considered a robust tool for the realistic analysis of the performance of thermoelectric generators and thermoelectric coolers. The foregoing will allow massive use of this type of device in industrial applications and its commercial accessibility.

Determination of the structural efficiency of short bridges according to their physical and economic characteristics

Pineda Rodríguez, J R | 2021-06-04

Bridges are structures designed and built to overcome natural and artificial obstacles. The analysis and design of bridges is carried out following principles of physics applied to engineering. The aim is to estimate the structural efficiency of short bridges according to their physical and economic characteristics through equations that measure the cost tendency, identifying which ones have the highest structural efficiency for a given length between supports. The design of short bridges was carried out by means of a mathematical modeling in a software based on finite elements. A comparative cost analysis was carried out for various types of short vehicular bridges designed with reinforced concrete decks supported by reinforced concrete beams; post-tensioned concrete beams; and structural steel beams. It was determined that the bridge with a reinforced concrete deck is the alternative with the best structural efficiency according to its physical and economic characteristics with spans of 12 meters and 18 meters. According to the estimated cost equations, it is concluded that, from 18.49 meters post-tensioned concrete bridges are the most efficient physically and economically. Structural steel bridges are the least structurally efficient for short bridges. Therefore, the construction of short vehicular bridges with structural steel is not feasible.

Evaluation of recycled asphalt pavement in Colombia

Yung Vargas, Yee Wan | 2022-01-06

Reclaimed asphalt pavements are obtained from existing pavements through recovery techniques and are used for new asphalt mixtures production with the inclusion of virgin aggregates and asphalt cement, constituting environmentally friendly mixtures at a lower total cost, by requiring fewer quantities of new materials. This research, unlike the studies found on the subject, focuses on the study of reclaimed asphalt pavement by analyzing its granulometric distribution and asphalt cement content. For this purpose, representative reclaimed asphalt pavement samples were taken from four Colombia cities, to verify their heterogeneity. The obtained reclaimed asphalt pavement was analyzed in the laboratory, to obtain the material granulometric distribution, through extraction and asphalt content tests, following Colombian regulations from the “Instituto Nacional de Vías”. The results show that the granulometry of all cities has a central tendency (average) that moves towards an upper limit in the 2 mm particles. When analyzing the granulometry separately of the four cities, it is observed that they present a different trend in their granulometry, which shows their heterogeneity. The asphalt cement content presented values between 4.0% and 5.0%.

Evaluation of the fire resistance of steel-reinforced concretefilled steel tubular columns with a circular cross-section

Rojas Suárez, J P | 2022-01-06

In the present investigation, an analysis of the fire resistance of the steel-reinforced concrete-filled steel tubular columns with circular cross-sections was carried out by means of numerical simulation. The development of the study was carried out by means of numerical simulation to predict the behavior of the column against fire. The results of the numerical model are validated by comparing the temperature levels obtained through experimental tests. From the results obtained, it is shown that the increase in the contact area between the steel and the concrete reduces the average temperature of the column, which implies a greater resistance to fire. The fire resistance of the columns with the steel profile designs are between 3.4 - 3.6 times higher compared to the column only made of concrete, which is an indication of the excellent performance of the steel-reinforced concrete-filled steel tubular columns with circular crosssections columns. In general, the methodology proposed in this research allows the analysis of the thermal physical phenomena of the different columns used for the construction of buildings.

Resistance under Marshall monotonic load for asphalt concrete mixtures

Yung Vargas, Yee Wan | 2022-01-06

The dense hot MDC-19 type asphalt mixes are considered, by the “Instituto Nacional de Vías” in Colombia, as continuous grading asphalt mixes (asphalt concrete). These constitute most of the surface course, in the structures of in-service pavements, being the object of study and research in different projects to ensure their durability. In the present investigation, unlike other investigations, the mechanical behavior under Marshall monotonic load was studied in the laboratory between MDC-19 dense type asphalt mixtures, comparing plant-produced and laboratory-produced asphalt mixtures. To carry out this process, samples of uncompacted asphalt mixtures were taken, produced in four fixed plants, with which Marshall-type briquettes were compacted. Likewise, samples of mineral aggregates and asphalt cement were obtained from the same plants, which constitute the mixtures raw material produced there. With these materials, briquettes with the same characteristics were mixed and compacted. Subsequently, the resistance under Marshall monotonic load was determined on the briquettes manufactured in plant and laboratory. The optimal asphalt cement content was compared between plant and laboratoryproduced mixtures. An increase in Marshall Stability was found in the briquettes made with plant-produced mixtures, while these required a greater amount of asphalt cement for their production.

First International Seminar on Physical Infrastructure (1st ISPI)

Yung Vargas, Yee Wan | 2022-01-06

The First International Seminar on Physical Infrastructure (1st ISPI) was an academic and scientific event organized by the Road Infrastructure Research Group and the Road Infrastructure Research Seedbed of the Universidad Francisco de Paula Santander, San José de Cúcuta, Colombia; the 1st ISPI was held from October 13 to 15, 2021. The purpose of the 1st ISPI was to allow the academic and scientific community, researchers, professors, professionals, and students, to share results and research proposals in the areas of Engineering, Mathematics, and Physics; during the 1st ISPI is presented 29 research work, of which 6 were plenary lectures from Spain, Brazil, Venezuela, and Colombia, and 23 talks, on different topics that allowed to the participants the to learn about the current state of the Physical Infrastructure, the Mathematical Modeling, the Physical and Numerical Modeling, the Physicochemical Phenomena in Engineering, the Advances in Materials Science and Engineering, the Simulation of PhysicalMathematical Problems in Engineering, and the Teaching and Research Techniques in Science and Engineering. The website of the conference is available at https://foristom.org/1ispi. On behalf of the organizing committee of the 1st ISPI, 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, and the Foundation of Researchers in Materials Science and Technology, for all the support technical and logistical received. Likewise, the organizing committee 1st ISPI thanks all who attended this edition of the event, and we are very proud to have carried out this event successfully that allowing the generation and effective transfer of new knowledge regarding the topics addressed during the event; we will be waiting for you at the 2nd ISPI in 2022. Finally, the editor hopes that those interested in the area of physical infrastructure can enjoy this reading, of the volume of the Journal of Physics: Conference Series (JPCS), which reflects a wide variety of current issues.

Economic and Environmental Multiobjective Optimization of a Hybrid Power Generation System using Solar and Wind Energy Source

Rojas Suárez, Jhan Piero | 2022-01-19

This article presents a comparison of energy generation using two methods of power production for different geographical locations. For this comparison, the HOMER software was used, which allows simulating generation systems with different energy sources. For the development of these simulations it was necessary to collect three parameters in the locations to be analyzed, which were wind speed, solar radiation and temperature. The photovoltaic array system was simulated using from 10 to 200 units with a constant value of one wind turbine, while for the wind turbine system, 1 to 9 units were used together with a constant value of 100 photovoltaic arrays. For the photovoltaic system, there is no major difference in the net project cost, the renewable fraction and the annual carbon dioxide production when using a greater number of arrays, but an increase in energy production is observed, a greater effect is obtained by changing the location of the system, analyzing the wind system a greater number of turbines increases the energy production, but also increase the annual carbon dioxide production and project cost, there is no significant difference between locations for the project cost the other parameters are affected. By using an optimization algorithm in the systems, the best performance was obtained in Puerto Bolivar using 105 photovoltaic arrays of 1kW and 3 wind turbines of 1.5MW.