Informatics Publishing Limited

Jorge Duarte Forero ¹, Guillermo E. Valencia ², Luis G. Obregon ³

Affiliations
1 Mechanical Engineering Department, DIMER Research Group, Universidad del Atlantico, Barranquilla, CO
2 Mechanical Engineering Department, KAI Research Group, Universidad del Atlantico, Barranquilla, CO
3 Chemical Engineering Department, Sustainable Chemical and Biochemical Processes Research Group, Universidad del Atlantico, Barranquilla, CO

Abstract

Background/Objectives: To make implementation of a thermodynamic diagnostic model to determine the rate of heat release in low displacement Diesel engines so that the performance of the combustion process can be quantified and sub-models of heat transfer can be adjusted; so that it can be applied in subsequent predictive modeling. Methods: With the pressure data in the combustion chamber and the set of variables composed of the pressure and temperature in the admission, fuel consumption, speed of rotation, injection pressure, compression ratio and environmental conditions, a thermodynamic model is defined. It allows quantifying how the heat release process occurs in the combustion process. Findings: The results allow verifying the influence of the compression ratio on the heat release process, finding that the rate of heat released increases with the increase of the variable under study. Likewise, it is verified that the most pronounced difference between the release rates for different compression ratios studied is in the premix combustion zone. Application: This methodology can be used for the process of optimization and redesign of thermal engines, to maximize the output power for the same fuel and operational conditions.

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Jorge Duarte Forero ¹, Guillermo E. Valencia ², Luis G. Obregon ³

Affiliations
1 Mechanical Engineering Department, DIMER Research Group, Universidad del Atlántico, Barranquilla, CO
2 Mechanical Engineering Department, KAI Research Group, Universidad del Atlántico, Barranquilla, CO
3 Chemical Engineering Department, Sustainable Chemical and Biochemical Processes Research Group, Universidad del Atlántico, Barranquilla, CO

Abstract

Background/Objectives: The implementation of a methodology for the calibration of a force sensor, applied to a commercial-type FSR for a seat occupancy detection application in a vehicle. This methodology is basedon the use of an Arduino^® board, to establish a direct conversion between the sensor output, and the measured variable, which in this case correspond to the force applied. Methods: With the study of the behavior of the sensor response when coupled with a conditioning circuit, and the following calibration of this, to program a direct conversion between the circuit output voltage and the force detected by the sensor. Findings: It was found that using the programming of the Arduino board, the force value given by the Arduino GUI, have a maximum deviation from the real ones of approximately 1%, which can be attributed to conversion issues, but for the application required, the system studied has a great potential to use. Application: To calibrate a FSR force sensor, using a circuit conformed by a conditioning signal system, the sensor and the transducer element between the sensor and the graphical interface on a PC.

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Jorge Duarte Forero ¹, Guillermo E. Valencia ², Luis G. Obregon ³

Affiliations
1 Mechanical Engineering Department, DIMER Research Group, Universidad del Atlantico, Barranquilla,, CO
2 Mechanical Engineering Department, KAI Research Group, Universidad del Atlántico, Barranquilla, CO
3 Chemical Engineering Department, Sustainable Chemical and Biochemical Processes Research Group, Universidad del Atlántico, Barranquilla, CO

Abstract

Background/Objectives: Thermodynamic study of advection phenomena relies on the analytical methods to solve a series of Partial Differential Equations (PDE) that generates from multi-dimensional problems, which becomes more and more complex, especially when a 2D or 3D temperature profile is required. Methods: For the solution of heat transfer problems with simultaneous advection-conduction phenomena, finite differences of 2nd, 4th and 6th order were used to approximate the solution of a two-dimensional PDE. Findings: The results show that a low discretization of the system, originated substantial errors in the application of the high order finite, but, when is correctly used, the numeric approximation shows with great precision the temperature profile for the simultaneous advection and conduction heat transfer. Application: To develop a method to accurately predict the temperature profile for complex heat transfer applications where simultaneous advection and conduction are takeninto account.

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Jorge Duarte Forero ¹, Guillermo E. Valencia ², Luis G. Obregon ³

Affiliations
1 Department of Mechanical Engineering, DIMER Research Group, Universidad del Atlantico, Barranquilla, CO
2 Department of Mechanical Engineering, KAI Research Group, Universidad del Atlantico, Barranquilla, CO
3 Department of Chemical Engineering, Sustainable Chemical and Biochemical Processes Research Group, Universidad del Atlantico, Barranquilla, CO

Abstract

Background/Objectives: To take into an account the effects of compressibility when studying the flow of any fluid, it is necessary to define a series of additional parameters in the nozzle analysis, which is a complex job to do in a manual strategy, leaving as a suitable option the use of numerical methods programmed in a commercial software (such as MATLAB^®). Methods: Variations were made in compressible flow parameters, such as initial pressure and temperature, and the Mach number, to study their influence over the pressure profile of the air inside a nozzle. Findings: The results show a low influence of the temperature over the pressure profile, a medium to high influence from its intake pressure, and a close relationship with the Mach number, getting even higher pressure drops when it only increases a bit. Application: To predict the behavior of the fluid flow through a nozzle, and to establish design and simulation criteria for these, when subjected to a particular application.

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Jorge Duarte Forero ¹, Guillermo E. Valencia ¹, Luis G. Obregon ²

Affiliations
1 Department of Mechanical Engineering, KAI Research Group, Universidad del Atlantico, Barranquilla, CO
2 Department of Chemical Engineering, Sustainable Chemical and Biochemical Processes Research Group, Universidad del Atlantico, Barranquilla,, CO

Abstract

Background/Objectives: The implementation of Design of Experiments as a tool for the study of process variables related to the operation of some types of industrial machinery, such as Continuous Tracked Vehicles, as a base for optimization processes that allow establishing an operational point with the most efficient use of these vehicles. Methods: Using a factorial design, a series of experiments were realized, with some process variables as design factors, each one arranged with two design levels. From these, statistical methods were used to validate the normal distribution of the results and at the same time, to establish mathematical expressions that correlate said parameters. Findings: The results allowed the determination of the factors that can be neglected in optimization processes, due to their low influence of the operation characteristics; besides, it was demonstrated that certain parameters, as the terrain, have little or no influence on the vehicle performance, which serves as a valid criterion to evaluate future investments inload transport systems. Application: To develop a tool for the prediction of the operation characteristics of Continuous Tracked Vehicles which will be used for the estimation of potential savings generated by more efficient use of these machines?

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Jorge Duarte Forero ¹, Guillermo E. Valencia ¹, Luis G. Obregon ²

Affiliations
1 Department of Mechanical Engineering, KAI Research Group, Universidad del Atlantico, Barranquilla, CO
2 Department of Chemical Engineering, Sustainable Chemical and Biochemical Processes Research Group, Universidaddel Atlantico, Barranquilla, CO

Abstract

Background/Objectives: The implementation of regression and correlation analysis as a tool for the modeling of industrial- scale milling processes, as a base for optimization processes that allow establishing a production regime with the highest consumption rate and therefore, a better process performance. Methods: Using the multivariate regression methods, a mathematical model to establish a correlation between the consumption rate and the factors that influence it was developed; in this process, a series of statistical analysis was developed to select the factors that generate an effect on the behavior of the consumption rate, at the same time, to determinate the best fit for the experimental data measured, using a statistical tool for the operations required. Findings: From the obtained results, it is shown that from the set of initial variables studied, only two (the humidity and the production), have a degree of correlation enough to be taken in account into post-processing operations; besides, it was found that the behavior of the consumption rate can be approximated as a linear combination of the relevant factors, with a better accuracy when compared to more complex fits, which in turn generates a model easy to handle in optimization processes Application: To develop a tool for the prediction of the behavior of consumption rate in milling processes, which will be used for the establishment of a more efficient production regime, where a better planification yields a lower energy consumption, with the same production level.

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Jorge Duarte Forero ¹, Guillermo E. Valencia ¹, Luis G. Obregon ²

Affiliations
1 Department of Mechanical Engineering, KAI Research Group, Universidad del Atlantico, Barranquilla, CO
2 Department of Chemical Engineering, Sustainable Chemical and Biochemical Processes Research Group, Universidad del Atlantico, Barranquilla, CO

Abstract

Background/Objectives: The implementation of a method for the characterization of polar (or spherical) robot manipulators for arc welding applications, based on the usage of mechanical simulation software to predict the behavior of the main kinetic variables of said mechanism, previous to its physical elaboration. Methods: With the application of simulation software, kinetic variables of a polar robot manipulator, such as velocities and accelerations, were determined using a commercial simulation package; to validate the simulation results, these were compared by the results given by the application of the theoretical model used for the study of polar manipulators, which is available in the literature. Findings: The results obtained by using the simulation package, shared the same behavior as the results obtained through the application of the theoretical model, with a little deviation from the theoretical results (less than 5%). Besides that, the simulation model allowed to obtain results to a higher speed than the solution of theoretical equations (harder to solve at hand) with the same accuracy, which is an important parameter when optimization processes are required. Application: To develop a tool for the kinetic analysis of polar robot manipulators for arc welding applications, using simulation software.

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