Contribution to the Experimental Characterization and 1-D Modelling of Turbochargers for IC Engines

At the end of the 19th Century, the invention of the Internal Combustion Engine (ICE) marked the beginning of our current lifestyle. Soon after the first ICE patent, the importance of increasing air pressure upstream the engine cylinders was revealed. At the beginning of the 20th Century turbo-machinery developments (which had started time before), met the ICE what represented the beginning of turbocharged engines. Since that time, the working principle has not fundamentally changed. Nevertheless, stringent emissions standards and oil depletion have motivated engine developments; among them, turbocharging coupled with downsized engines has emerged as the most feasible way to increase specific power while reducing fuel consumption. Turbocharging has been traditionally a complex problem due to the high rotational speeds, high temperature differences between working fluids (exhaust gases, compressed air, lubricating oil and cooling liquid) and pulsating flow conditions. To improve current computational models, a new procedure for turbochargers characterization and modelling has been presented in this Thesis. That model divides turbocharger modelling complex problem into several sub-models for each of the nonrecurring phenomenon; i.e. heat transfer phenomena, friction losses and acoustic non-linear models for compressor and turbine. A series of ad-hoc experiments have been designed to aid identifying and isolating each phenomenon from the others. Each chapter of this Thesis has been dedicated to analyse that complex problem proposing different sub-models. First of all, an exhaustive literature review of the existing turbocharger models has been performed. Then a turbocharger 1-D internal Heat Transfer Model (HTM) has been developed. Later geometrical models for compressor and turbine have been proposed to account for acoustic effects. A physically based methodology to extrapolate turbine performance maps has been developed too. That model improves turbocharged engine prediction since turbine instantaneous behaviour moves far from the narrow operative range provided in manufacturer maps. Once each separated model has been developed and validated, a series of tests considering all phenomena combined have been performed. Those tests have been designed to check model accuracy under likely operative conditions. The main contributions of this Thesis are the development of a 1-D heat transfer model to account for internal heat fluxes of automotive turbochargers; the development of a physically-based turbine extrapolation methodology; the several tests campaigns that have been necessary to study each phenomenon isolated from others and the integration of experiments and models in a comprehensive characterization procedure designed to provide 1-D predictive turbocharger models for ICE calculation.Reyes Belmonte, MÁ. (2013). Contribution to the Experimental Characterization and 1-D Modelling of Turbochargers for IC Engines [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/34777TESI

Desde la Iniciativa Empresarial hacia el éxito pasando por Metodologías Ágiles e Ingeniería del Software

Las asignaturas de los nuevos grados universitarios surgidos de la implantación del Espacio Europeo de Educación Superior (EEES) funcionan en la mayoría de casos como islas de conocimiento. La coordinación entre asignaturas, si existe, se limita a evitar el solapamiento de contenidos. A pesar de ello, existen interesantes propuestas de coordinación entre asignaturas en las que se suele trabajar sobre un proyecto común. Como consecuencia, el alumnado no percibe las asignaturas como entes independientes y el resultado de su trabajo sirve para evaluar la adquisición de competencias tanto específicas como genéricas. Una de las principales claves del éxito de estas propuestas es elegir asignaturas claramente complementarias y proponer un proyecto adecuado a realizar en común. En este trabajo presentamos una experiencia docente en la que las asignaturas no se eligen tanto por su complementariedad y después se propone un proyecto, sino que el nexo de unión en nuestro caso lo define un objetivo y a partir del mismo se eligen las asignaturas que hemos creído más adecuadas para guiar al alumno hacia él. Este objetivo consiste en el planteamiento y desarrollo de una idea de negocio que luego se convertirá en un proyecto informático que tras su planificación pueda ser implementado. Para conseguirlo se han elegido tres asignaturas del Grado en Ingeniería Informática de la Universitat Jaume I: Iniciativa Empresarial, en la cual se plantea un plan de negocio; Métodos Ágiles, en la cual se aplica la metodología Scrum Manager en la planificación y seguimiento del proyecto surgido de dicho plan; y Taller de Ingeniería del Software, en la cual se implementa y prueba la aplicación web resultante. Además creemos que una de las claves del éxito de la experiencia es el haber implicado a otros actores dentro del proceso de coordinación, tales como las empresas y el Parque Científico, Tecnológico y Empresarial de la Universitat Jaume I. Aplicando así el Modelo de la Triple Hélice en un contexto educativo.The courses offered by the new university degrees that have resulted from the implementation of the European Higher Education Area (EHEA) are like isolated enti-ties. Coordination between courses, if there is any, is limited to avoiding overlapping of contents. However, there are some interesting proposals for coordination between courses in order to work towards a common project. As a result, students do not perceive the courses as independent entities and the outcome of their work is to evaluate the acquisition of both specific and general skills. One of the main keys to the success of these proposals is to choose complementary courses and propose a suitable, common project to be carried out in conjunction with the other courses.In this paper we present an educational experience in which the courses are not chosen for their comple-mentarity and then the proposed project is carried out. The link in our case defines an objective, and the courses that we have considered would be best suited to lead the students toward this objective are then chosen. This goal consists of the planning and development of a business idea that will later become a computer project that after planning can be implemented. To achieve this we have selected three courses in the Computer Engineering Degree at the Universitat Jaume I: Entrepreneurship, in which a Business Plan is developed; Agile Methods, in which the Scrum Manager Methodology is applied for planning and controlling the project emerged from the mentioned plan; and Workshop on Software Engineering, in which the resulting web application is implemented and tested. Furthermore, we believe that one of the keys to the success of the experience is to have other actors involved in the coordination process, such as the companies and the Science, Technology and Business Park at the Universitat Jaume I, thus applying the Triple Helix Model in an educational context

How to implement scrum manager in the software engineering route?

Ponència presentada a 13 th International Technology, Education and Development Conference, Valencia, 11-13 març 2019.Teaching in Software Engineering has evolved in recent years at the same time that software development methodologies have. Therefore, there are a lot of good examples in the literature on how to use Agile Methods in the teaching of the subjects of this track. Most of them focused on explaining the teaching organization, the subsequent evaluation and the obtained academic results, as well as their benefits. However, there are still unanswered questions when implementing the principles of an agile methodology such as Scrum Manager in teaching practice. This paper presents the result of a teaching experience of coordination of subjects in the context of Software Engineering carried out during four academic years. This has been formulated as best practices including the improvements that teachers have achieved in teaching after gathering feedback from students and the collaborative business environment. The main objective is to offer a help guide for teachers who want to use Scrum Manager in their subjects but who sometimes find problems that are not usually collected in the literature

El rendimiento académico de los alumnos de primaria que cursan estudios artísticos-musicales en la Comunidad Valenciana

Esta tesis analiza las repercusiones que tiene el estudio de la música en el rendimiento académico del niño y niña de primaria. Para ello se han investigado los principales agentes que confluyen en el proceso de aprendizaje y enseñanza musical: el alumnado de conservatorio / sociedad musical y los profesores que imparten docencia musical. Se realiza en un contexto musicalmente prolífero como es la Comunidad Valenciana que también es referente a nivel nacional e internacional en cuanto a intérpretes y compositores. En el transcurso de ese análisis se tratan cuestiones que condicionan el rendimiento del alumnado: el currículo establecido en España y en la Comunidad, el concepto de rendimiento, el nivel de los alumnos a través de los estudios de rendimiento o el contenido extra musical que trabajan los alumnos que estudian música. Para ello la tesis cuenta con dos grandes apoyos. El primero lo constituyen los datos ofrecidos por diferentes escuelas públicas de etapa primaria de la Comunidad Valenciana. Y el segundo gran apoyo lo constituye la propia experiencia como docente de música de la autora en la escuela primaria. La tesis parte de los estudios pedagógicos y clínicos sobre la respuesta de las personas hacia la música, que es el germen de esta tesis como se refleja en la introducción. Se han establecido tras esa introducción seis apartados que constituyen el corpus de la tesis: el estado de la cuestión en este tipo de estudios, la estructura de la investigación concreta llevada a cabo, el desarrollo musical en el seno del desarrollo psicoevolutivo del alumno, la educación musical en la escuela primaria y en las sociedades musicales y la relación de la música con el resto de materias que es el reflejo más evidente de la repercusión música en el rendimiento. Los datos de tipo cualitativo y cuantitativo facilitados por los colegios y el análisis de aula hace posible que este estudio de caso describa una realidad que muchos docentes intuyen y que se expone de manera más concreta con este estudio. La música influye en la inteligencia del alumno, crea conexiones desde su propio sentido de ser. Trabaja conceptos matemáticos también conceptos lingüísticos o conocimientos del entorno. La capacidad motriz fina y el control motor es también beneficiada asi como la capacidad plástica a través de la audición. De este modo gracias a los datos facilitados por los maestros de música de los centros públicos de la Comunidad y la propia investigación diaria de aula se ha podido llegar a la conclusión de que cualquier niño mejora su rendimiento cuando estudia música, y aún más los niños que se dedican a su estudio a nivel extraescolar. Estos niños (que en la tesis aparecen bajo el nombre de niños/as-músico) desarrollan otro tipo de estrategias de índole social y emocional muy positivas y beneficiosas para su autoestima y para el comportamiento en el aula, el trabajo en equipo, la responsabilidad ante un trabajo bien hecho en las audiciones y conciertos, etc. Esta tesis resulta novedosa porque lleva la investigación a un ámbito muy concreto y fácilmente identificable y hace más fácil al docente el acceso a conocimientos que pueden mejorar su acción pedagógica y como resultado el aprendizaje de sus alumnos. Otra novedad resulta el estudio de caso en el ámbito pedagógico, pues en este caso es importante tener en cuenta a los participantes directos de la enseñanza musical, los maestros y los alumnos de música. En resumen, es una tesis que pretende la reflexión del profesorado de música sobre su materia y sobre cómo esta puede llegar a influir en el rendimiento académico general de sus alumnos.The present Doctoral Thesis analyzes the effects of musical studies in the academic efficiency of elementary students. For that reason main factors in learning and musical teaching procedure have been investigated; these are the students of Music Conservatories/ Music Academies and music professionals. This Doctoral Thesis has been carried on the Comunidad Valenciana that is one of the best examples of musical tradition and international projection of its musicians and composers. Along this analysis questions affecting the academic study are developed, the study plan followed in Spain and in the Comunidad Valenciana, the definition of academic efficiency, students’ level using works about academic effectiveness and the extra knowledge achieved with musical studies. The thesis is based on two fundamental aspects. The first one is the data supported for several Public Elementary Schools of the Comunidad Valenciana. And the second one is the experience of the author of the present work in his career of a music teacher in an Elementary School. The departure point of the present Thesis are the pedagogical and clinic studies about the response of people towards the music, those studies have given rise to this work as is reflected in the introduction section. Quantitative and qualitative data provided by Elementary Schools and the class analysis have made possible this action research describing what most of teachers have ever noticed and what is exposed in a concise way with this study. Intrinsically the study of music creates connections with other areas contributing in student’s intelligence. The thesis is original due to its research is focused in a specific area neatly identifiable making easier to the professor the access to knowledge which could improve his pedagogical job and consequently could improve students’ learning abilities. Another original aspect in this Thesis is the class analysis in the pedagogical area, since in this case it is important to keep in mind the direct participants in musical teaching procedure, these are the music professors and music students

Assessment of a methodology to mesh the spatial domain in the proximity of the boundary conditions for one-dimensional gas dynamic calculation

[EN] Solution of governing equations for one-dimensional compressible unsteady flow has been performed traditionally using a homogenously distributed spatial mesh. In the resulting node structure, the internal nodes are solved by applying a shock capturing finite difference numerical method whereas the solution of the end nodes, which define the boundary conditions of the pipe, is undertaken by means of the Method of Characteristics. Besides the independent solution of every method, the coupling between the information obtained by the method of characteristics and the finite difference method is key in order to reach a good accuracy in gas dynamics modeling. The classical spatial mesh could provide numerical problems leading the boundary to generate lack of mass, momentum and energy conservation because of the interpolation methodology usually applied to draw the characteristics and path lines from its departure point at calculation time to the end of the pipe during the next time-step. To deal with this undesirable behavior, in this work a modification of the traditional grid including an extra node close to the boundary is proposed in order to explore its ability to provide numerical results with higher conservation fulfillment. © 2010 Elsevier Ltd.J.R. Serrano; Arnau Martínez, FJ.; Piqueras, P.; Reyes Belmonte, MA. (2011). Assessment of a methodology to mesh the spatial domain in the proximity of the boundary conditions for one-dimensional gas dynamic calculation. Mathematical and Computer Modelling. 54:1747-1752. doi:10.1016/j.mcm.2010.11.073S174717525

Design and Testing a Bespoke Cylinder Head Pulsating Flow Generator for a Turbocharger Gas Stand

Most turbocharger gas stands are designed to map performance under steady flow conditions. However, when connected to an internal combustion engine (ICE), the turbine is exposed to pulsatile flow. In order to enable a full analysis of the unsteady flow and turbocharger performance, it is crucial to quantify unsteady flow effects in the gas stand tests. This paper presents the development and use of bespoke experimental hardware that aims to generate flows in a gas-stand with characteristics similar to that produced by an ICE. This is achieved using a specially modified cylinder head placed between the hot supply and the turbocharger. The device has been designed, manufactured and tested on the gas stand showing its usefulness to study the energy exchange between the engine and the turbine. Testing a turbocharger where a cylinder is deactivated showed large changes in the instantaneous turbocharger speed, pressure and temperature profiles. These unsteady characteristics resulted in a change in the turbocharger behaviour. The insights into unsteady characteristics is expected to contribute to both engine calibration and turbocharger design. It also demonstrates the novelty of the approach in delivering a means to replicate hot, engine-like flow unsteadiness and thereby a wider, more representative data set.<br/

Determination of heat flows inside turbochargers by means of a one dimensional lumped model

In the present paper, a methodology to calculate the heat fluxes inside a turbocharger from diesel passenger car is presented. The heat transfer phenomenon is solved by using a one dimensional lumped model that takes into account both the heat fluxes between the different turbocharger elements, as well as the heat fluxes between the working fluids and the turbocharger elements. This heat transfer study is supported by the high temperature differences between the working fluids passing through a typical diesel turbocharger. These flows are the hot exhaust gases coming from the diesel engine exhaust passing through the turbine, the fresh air taken by the compressor, and the lubrication oil passing through the housing. The model has been updated to be used with a new generation of passenger car turbochargers using an extra element in the heat transfer phenomenon that is the water cooling circuit. This procedure allows separating the aerodynamic from the heat transfer effects, permitting to study the behavior of compressor and turbine in a separated way. (C) 2011 Elsevier Ltd. All rights reserved.Olmeda González, PC.; Dolz Ruiz, V.; Arnau Martínez, FJ.; Reyes Belmonte, MA. (2013). Determination of heat flows inside turbochargers by means of a one dimensional lumped model. Mathematical and Computer Modelling. 57(7-8):1847-1852. doi:10.1016/j.mcm.2011.11.078S18471852577-

Propiedades psicométricas de la Escala de Motivación Académica de los Adolescentes (EMAA) en una muestra representativa de estudiantes de instituto de la República Dominicana

Within the growing body of research that has focused on academic success, academic motivation has gathered considerable attention. The aim of this this research is to present the first validation of the Adolescents’ Academic Motivation Scale (AAMS). Total sample was composed by 1712 students of secondary education from two districts in the Dominican Republic. The main measurement outcome was the AAMS. Results from the CFA were satisfactory: χ2(5) = 57.73, p &lt; .001; CFI = .970; RMSEA = .079 [.061, .097], and SRMR = .024. IRT analyses favored the two-parameter logistic model, indicating that items were not equally discriminant. Structural Equation Model with latent variables in which academic motivation was a significant predictor of grades resulted in excellent fit: χ2(53) = 182.76, p &lt; .001; CFI = .980; RMSEA = .038 90% CI [.032, .044], and SRMR = .025. In sum, this work presents an exhaustive psychometric analysis of the AAMS in a representative sample of high school Dominican students.Entre el creciente cuerpo de investigación que se ha centrado en el éxito académico, la motivación académica ha captado considerable atención. El objetivo de esta investigación es presentar la primera validación de la Escala de Motivación Académica de los Adolescentes (EMAA). La muestra total estuvo compuesta por 1712 estudiantes de secundaria de dos distritos de la República Dominicana. La medida principal fue la EMAA. Los resultados del AFC fueron satisfactorios: χ2(5) = 57.73, p &lt; .001; CFI = .970; RMSEA = .079, 90% CI [.061, .097], y SRMR = .024. Los análisis de TRI favorecieron al modelo logístico de dos parámetros, indicando que los ítems no fueron igualmente discriminativos. El Modelo de Ecuaciones Estructurales en el que la motivación académica predecía de forma estadísticamente significativa las calificaciones obtuvo un ajuste excelente: χ2(53) = 182.76, p &lt; .001; CFI = .980; RMSEA = .038 [.032, .044], and SRMR = .025. En resumen, este trabajo presenta un exhaustivo análisis psicométrico de la EMAA en una muestra representativa de estudiantes dominicanos de instituto