Browsing by Author "Rubio, A."
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Item A comparative study on the performance of ventilated brake discs manufactured in different advanced materials(2001) Goñi, J.; Mitxelena, I.; Rubio, A.; Coleto, J.; Terrón, A.; García, A.; Sánchez, J.; Centros PRE-FUSION TECNALIA - (FORMER); Tecnalia Research & Innovation; MercadoTwo different aluminium alloy materials have been used to produce ventilated brake discs, on one hand, AS17G0.6 hypereutectic alloy and on the other hand, AS7G0.6 reinforced with 20% in wt. of SiC particles. The casting production technique used has been Low Pressure Casting (LPC) and some of the brake discs have been heat treated using a T6 treatment. Once the ventilated brake discs were produced and machined, they were tested in a dynamometer in order to compare the performance under service conditions of the aluminum alloy and grey cast iron (GCI) discs currently used in the market.Item Implementation of an operational oceanometeorological system for the basque country(2010) Gaztelumendi, S.; González, M.; Egaña, J.; Rubio, A.; Gelpi, I. R.; Fontán, A.; De Alda, K. Otxoa; Ferrer, L.; Alchaarani, N.; Mader, J.; Uriarte, Ad; WEATHER AND CLIMATE INTELLIGENCE FOR BUSINESSIn this contribution, the most relevant aspects of the ITSASEUS project are shown. Under this acronym, several works are carried out by the partners (EUVE and AZTI-Tecnalia) in order to implement an operational oceano-meteorological system for providing daily a 72-hour forecast for the Basque Country region and its influence areas. The system combines meteorological, wave and hydrodynamic modelling at several scales together with field observations. The meteorological model used is the MM5 mesoscale model with a nested domains configuration, in which the GFS (Global Forecast System) is used for providing the lateral and initial conditions. The wave and hydrodynamic models used are the Wavewatch-III and ROMS, respectively. Preliminary results are promising and show the forecast subsystems ability to predict oceano-meteorological variables in the Basque Country region.Item Influence of the processing parameters on glass mat reinforced thermoplastic (GMT) stamping(1992) Rubio, A.; Eguizabal, P.; Mendizabal, M. A.; Liceaga, J. F.; Tecnalia Research & Innovation; POLIMEROS; Centros PRE-FUSION TECNALIA - (FORMER)The influence of both the processing parameters and mould geometry on the mechanical properties and surface quality of polypropylene based glass mat reinforced thermoplastic (gmt) parts was studied. The parameters controlled were the forming pressure, the temperature in the surface of the blank, and the mould temperature. The influence of the geometry was also studied using three different moulds. It was seen that the mechanical properties did not vary substantially for the ranges of temperature and pressure used. Some differences were seen among the data collected from different moulds and a correlation existed between the surface quality of the parts and the mould temperature and design.Item Natural fibre composites for automotive applications(2005) Rubio, A.; Elizetxea, C.; Calleja, N.; Gaztelumendi, I.; Gaballah, I.; Mishra, B.; Solozabal, R.; Tanaka, M.; POLIMEROS; Centros PRE-FUSION TECNALIA - (FORMER)The main advantage of the use of composite materials is related to their intrinsic lightweight. In this way, labour and transport costs will be strongly decreased, and the total weight of the manufactured part will be minimised. The reduction of weight implies a considerable reduction of fuel consumption with the consequent respect to the environment. Although glass fibres, as plastics, are not intrinsically harmful to the environment, some of their products can be dangerous or, at least, environment "unfriendly". The health hazards of dealing with glass fibres have been already mentioned. A second drawback of these materials regards their recyclability because it requires costly separation procedures. It is clear that from this point of view natural fibre offer more possibilities for a complete recyclability allowing the development of «eco-waste» technologies and products. This work has been carried out within the European Growth Project G5RD-CT1999-00147 "Eco-Efficient Technologies and Products based on Natural Fibre Composites-ECOFINA".Item ROCOV scheme for Fault Detection and Location in HVDC sytems(2019-07) Díaz, J.; Abarrategi, O.; Larruskain, D.M.; Perez-Basante, A.; Rubio, A.; POWER ELECTRONICS AND SYSTEM EQUIPMENTA reliable DC fault protection system is essential for the development of HVDC grids. Therefore, this paper deals with the voltage derivative ROCOV scheme to locate and detect DC faults. The algorithm is able to differentiate internal and external faults considerably fast. The proposed algorithm is analyzed in a HVDC grid with different fault case scenarios. Finally, the ROCOV protection thresholds are discussed.Item Silicate chain formation in the nanostructure of cement-based materials(2007) Ayuela, A.; Dolado, J. S.; Campillo, I.; De Miguel, Y. R.; Erklzia, E.; Sánchez-Portal, D.; Rubio, A.; Porro, A.; Echenique, P. M.; Tecnalia Research & Innovation; Tecnología; ECOEFICIENCIA DE PRODUCTOS DE CONSTRUCCIÓNCement-based materials are ubiquitous in almost all built environment. In spite of this, little is known about the formation and the role played by the silicate chains always present in the cement nanostructure. By means of first principles simulations we provide compelling evidence on the pivotal role played by certain ionic species in the formation of the silicate chains inside the cementitious matrix. Moreover, we corroborate the experimental evidence which shows that the length of the most stable chains with m Si atoms follows a magic-number sequence: m=3n-1 with n=1,2,... Our results have been applied in the development of new higher performance cement-based materials by adding nanosilica.Item Ventilated brake discs manufactured in aluminium matrix composites and hypereutectic aluminium alloys(2003) Goñi, J.; Coleto, J.; Egizabal, P.; Rubio, A.; García, A.; Sanchez, J.; Centros PRE-FUSION TECNALIA - (FORMER); Mercado; Tecnalia Research & InnovationTwo different aluminium alloy materials have been used to produce ventilated brake discs, on one hand, AS17G0.6 hypereutectic alloy and on the other hand, AS7G0.6 reinforced with 20% in wt. of SiC particles. The casting production technique used has been Low Pressure Casting (LPC) and some of the brake discs have been heat treated using a T6 treatment. Once the ventilated brake discs were produced and machined, they were tested in a dynamometer in order to compare the performance under service conditions of the aluminium alloy and grey cast iron (GCI) discs currently used in the market.