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230 244 190 ; S ; [EN] Wind energy importance has increased over the past decades. Energy generation by small turbines installed near urban locations has experienced noticeable growth. This work is focused on the development of a design methodology for a low power blade well suited for all the wind operation conditions. First, a complete Design of Experiments will be presented using the low computational cost tool Blade Element Momentum Theory (BEMT) in order to discard those designs which are clearly not suited to the requirements of the system. Later, the remaining were analyzed using a Computational Fluid Dynamics (CFD) methodology in order to account for three dimensional effects. The value of the left slope of the non-dimensional power curve has been found to be a key parameter for the design. This methodology has been validated with experimental results available from NREL Phase VI wind turbine, allowing to conclude that BEMT is capable to provide with pre-design accurate results which, nevertheless, should corrected by CFD. The results of the proposed design are analyzed and compared to the CFD predictions of a commercial existing blade designed to comply with similar working. For the proposed design, predictions indicate better behavior in terms of maximum power and controllability. Torregrosa, AJ.; Gil, A.; Quintero-Igeño, P.; Tiseira, A. (2019). Enhanced design methodology of a low power stall regulated wind turbine. BEMT and MRF-RANS combination and comparison with existing designs. Journal of Wind Engineering and Industrial Aerodynamics. 190:230-244. https://doi.org/10.1016/j.jweia.2019.04.019

1 19 13 11 ; S ; [EN] Over the past few decades, the aerodynamic improvements of turbocharger turbines contributed significantly to the overall efficiency augmentation and the advancements in downsizing of internal combustion engines. Due to the compact size of automotive turbochargers, the experimental measurement of the complex internal aerodynamics has been insufficiently studied. Hence, turbine designs mostly rely on the results of numerical simulations and the validation of zero-dimensional parameters as efficiency and reduced mass flow. To push the aerodynamic development even further, a precise validation of three-dimensional flow patterns predicted by applied computational fluid dynamics (CFD) methods is in need. This paper presents the design of an up-scaled volute-stator model, which allows optical experimental measurement techniques. In a preliminary step, numerical results indicate that the enlarged geometry will be representative of the flow patterns and characteristic non-dimensional numbers at defined flow sections of the real size turbine. Limitations due to rotor-stator interactions are highlighted. Measurement sections of interest for available measurement techniques are predefined. The authors disclose receipt of the following financial support for the research, authorship, and/or publication of this article: This work was partly sponsored by the program "Ayuda a Primeros Proyectos de Investigacion (PAID-06-18), Vicerrectorado de Investigacion, Innovacion y Transferencia de la Universitat Politecnica de Valencia (UPV), Spain". The support given to Ms. N.H.G. by Universitat Politecnica de Valencia through the "FPI-Subprograma 2" (No.FPI-2018-S2-1368) grant within the "Programa de Apoyo para la Investigacion y Desarrollo (PAID-01-18)" is gratefully acknowledged Tiseira, A.; Navarro, R.; Inhestern, LB.; Hervás-Gómez, N. (2020). Design and Numerical Analysis of Flow Characteristics in a Scaled Volute and Vaned Nozzle of Radial Turbocharger Turbines. Energies. 13(11):1-19. ...

[EN] Nowadays, the turbocharger has become one of the key components for automotive spark-ignition engine improvements (fed with both liquid and gaseous fuels), as a support for the boosting and downsizing concept to reduce fuel consumption and exhaust emission. In gasoline engines, the usage of the waste-gate valve typically regulates the maximum boost pressure in the turbocharger system, to protect the engine and the turbocharger at high engine speeds. To improve the transient response at low engine speeds two-stage turbocharger is widely used. Two-stage systems are composed of several valves to regulate the flow to control the boosting of the system. Like, a by-pass valve between the turbines, a check valve between the compressor and a waste-gate valve for the low-pressure turbines. This paper deals with a methodology for characterizing the discharge coefficient of an electronic waste-gate valve in the turbocharger. To estimate the gas flow over the same in one-dimensional models, an empirical model is correlated and validated. For this, a constant stream experimental work has been carried out on a test rig at different valve position openings, with high turbine inlet temperatures. Finally, an optimal MAP of discharge coefficient has been drawn out through interpolation method, which can integrate into the full one-dimensional turbocharged engine model system, to calculate the actual mass flow through the waste-gate valve. ; The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was partially funded by FEDER and Government of Spain through Project TRA2016-79185-R. ; Serrano, J.; Arnau Martínez, FJ.; Tiseira ., AO.; Samala, V. (2017). Experimental procedure for the characterization of turbocharger s waste-gate discharge coefficient. Advances in Mechanical Engineering. 9(10):1-9. https://doi.org/10.1177/1687814017728242 ; S ; 1 ; 9 ; 9 ; 10

1 9 10 ; S ; [EN] Nowadays, the turbocharger has become one of the key components for automotive spark-ignition engine improvements (fed with both liquid and gaseous fuels), as a support for the boosting and downsizing concept to reduce fuel consumption and exhaust emission. In gasoline engines, the usage of the waste-gate valve typically regulates the maximum boost pressure in the turbocharger system, to protect the engine and the turbocharger at high engine speeds. To improve the transient response at low engine speeds two-stage turbocharger is widely used. Two-stage systems are composed of several valves to regulate the flow to control the boosting of the system. Like, a by-pass valve between the turbines, a check valve between the compressor and a waste-gate valve for the low-pressure turbines. This paper deals with a methodology for characterizing the discharge coefficient of an electronic waste-gate valve in the turbocharger. To estimate the gas flow over the same in one-dimensional models, an empirical model is correlated and validated. For this, a constant stream experimental work has been carried out on a test rig at different valve position openings, with high turbine inlet temperatures. Finally, an optimal MAP of discharge coefficient has been drawn out through interpolation method, which can integrate into the full one-dimensional turbocharged engine model system, to calculate the actual mass flow through the waste-gate valve. The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was partially funded by FEDER and Government of Spain through Project TRA2016-79185-R. Serrano, J.; Arnau Martínez, FJ.; Tiseira ., AO.; Samala, V. (2017). Experimental procedure for the characterization of turbocharger s waste-gate discharge coefficient. Advances in Mechanical Engineering. 9(10):1-9. doi:10.1177/1687814017728242

[EN] During the last years, it is well known that the curricula of the different engineering firms have undergone drastic changes in all the countries belonging to the European Union. Specifically, one of the concepts that can be derived from the application of the Bologna Plan, and with which the Universitat Politècnica de València is specially committed, is the need to provide the student with a series of transversal competences, common to all similar degrees. , that are of help to him during the development of his professional life. One of the most widespread methods for the development of these competences is the design of group work for practical application. This work proposes a group project, developed within the framework of the subject of the third year of the Aerospace Engineering Degree (GIA), consisting of the design and construction of a glider demonstrator, with the aim of treating, jointly, several of the specific and transversal competences of the degree. A detailed description will be made of the design of the project and an analysis of the results obtained after its application, from the academic year 2015-2016 in the subject Aerospace Technology II ; [ES] Durante los últimos años, es bien sabido que los planes de estudio de las diferentes ingenierías han sufrido drásticos cambios en todos los países pertenecientes a la Unión Europea. En concreto, uno de los conceptos que se pueden derivar de la aplicación del Plan Bolonia, y con el que la Universitat Politècnica de València está especialmente comprometida, es la necesidad de proporcionar al alumno una serie de competencias trasversales, comunes a todas las titulaciones semejantes, que le sean de ayuda durante el desarrollo de su vida profesional. Uno de los métodos más extendidos para el desarrollo de estas competencias consiste en el diseño de trabajos en grupo de aplicación práctica. Este trabajo propone un proyecto grupal, desarrollado en el marco de la asignatura de tercer curso del Grado de Ingeniería Aeroespacial (GIA), consistente en el ...