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The transport of hydrogen isotopes through the elements that make up a fusion reactor, and their corresponding interaction with these materials, have a direct impact on its operation. Consequently, it is essential to master in advance their transport parameters in the different materials proposed to constitute the elements that will compound the fusion reactors, and, consequently, this is one of the main lines of fusion investigation. For reasons of technology, safety and viability, it would be desirable to have the possibility of experimenting only with protium and, from these values, to extrapolate those of deuterium and, above all, tritium. To do so, the classical atomic theory establishes that the ratio of these parameters is inversely proportional to square root of their mass ratio. However, discrepancies have been detected, so its verification has become fundamental. For this reason, this study presents the analysis of a series of tests of permeability carried out at the Fusion Materials Laboratory (UPV/EHU) using protium and deuterium with some samples of SS316 and EUROFER steels, in order to contrast the isotope effect, as well as the variables that could influence its adjustment. The results show that 316 steels present an isotope effect much closer to the theoretical one, while EUROFER steels differ more, increasing their isotopic ratio of permeabilities with temperature. In both cases, the trends are in line with published results.

The characterization of hydrogen transport parameters is essential for a good prediction of its behavior and a correct design of the elements that will make up nuclear fusion reactors. It is therefore essential to determine the isotopic ratio of the transport parameters between protium (H), deuterium (D) and tritium (T), both for economic and safety reasons. Classical theory predicts that the ratio of their diffusivities and permeabilities should be proportional to the inverse square root of their atomic mass, while solubility values would be independent of their masses, but there are discrepancies in the literature. Despite this, it has not yet been possible to obtain either a correct value for the ratio or any uniform conclusion on the matter. This article presents a review of the works published in the field of the isotope effect of hydrogen permeability and diffusivity to date, focusing on protium and deuterium isotopes, which are the isotopes that have been most extensively analyzed experimentally. The conclusion is clear: the theoretical value cannot be stated to be correct and the results are very varied, although they seem to be related to the microstructure of the material tested. In addition, some factors that could have an influence on it have been analyzed, which would be interesting to take into account for future studies.

The current energy consumption system requires a radical change due to obvious factors, especially environmental problems, but also due to sustainability over time. Therefore, it is essential to find alternatives to replace the fossil fuels that are so widely used today. In this context, nuclear fusion energy is presented as a technological option that can solve many of the problems that will arise in the medium term. Throughout the article, the most important characteristics of this energy source will be exposed, as well as the theoretical basis of this technology. In addition, the development of technology over time, the status of the current ITER international project and the main objectives it pursues will be presented. Finally, and taking into account all the previous points, a presentation of the Fusion Materials Laboratory located at the Faculty of Engineering Bilbao (EIB/BIE) will be made, explaining the goals that it satisfies in order to understand its need and developing the description of the different facilities.; Gaur egun daukagun energia-kontsumoaren sistemak erabateko aldaketaren beharra du, faktore nabariengatik, batez ere suertatzen diren ingurumen-arazoengatik, baina baita denboran zeharreko jasangarritasunagatik ere. Hori dela eta, ezinbestekoa da alternatibak aurkitzea hainbeste erabiltzen diren erregai fosilak ordezkatzeko. Testuinguru horretan, fusio-energia nuklearra aurkezten da epe ertainera sortuko diren arazo asko konpon ditzakeen aukera teknologiko bezala. Artikuluan zehar, energia-iturri horren ezaugarri garrantzitsuenak azalduko dira; bai eta teknologiaren oinarri fisikoak ere. Horrez gain, teknologiak denboran zehar izandako garapena, gaur egungo ITER nazioarteko proiektuaren egoera eta horrek bilatzen dituen helburu nagusiak aurkeztuko dira. Azkenik, aurreko puntu guztiak kontuan hartuz, Bilboko Ingeniaritza Eskolan dagoen Fusio Materialen Laborategiaren aurkezpena egingo da, asetzen dituen beharrak azalduz haren eginkizuna ulertzek

The objective of this study was to characterize radon concentrations registered in the Radiological Surveillance Network of the Basque country in relation to local meteorological parameters, and to determine its behaviour under heatwave events. For this purpose, radon measurements and meteorological parameters from June 2012 to June 2015 were analysed at two sites, Bilbao and Vitoria (northern Spain), in a region characterized by complex orography, causing large temporal and spatial variability in meteorological conditions. Yearly, seasonal, and diurnal cycle differences and similarities were investigated at both sites. The temporal evolution of radon concentration was analysed at both sites during the two heatwave periods officially identified by the State Meteorological Agency (8–11 August 2012 and 17–23 August 2012). The analysis revealed two different patterns of radon concentrations, in terms of both time and intensity, under this synoptic pattern, making it also possible to identify regional transport channels of radon concentrations between the two sites. This set of results evidences the adequate position of both stations to represent the spatial and temporal evolution of radiological variables continuously in this region.

This paper presents a meteorological approach to identify local and remote sources driving the variability of surface daily radon concentrations. To this purpose, hourly 222Rn concentration and surface meteorological measurements, and air mass trajectories at Bilbao station (northern Iberian Peninsula) during the period 2017–2018 have been taken as reference. To investigate the potential transport pathways and potential 222Rn sources, the backward trajectory cluster analysis, trajectory sector analysis (TSA), and potential source contribution function (PSCF) are applied. On average, the diurnal 222Rn cycle shows the expected behaviour, with larger concentrations during the night and minimum concentrations during the daylight hours, with differences in the seasonal amplitudes. According to daily differences between maximum and baseline values, 222Rn daily cycles were grouped into six groups to identify meteorological conditions associated with each amplitude, and potential source areas and transport routes of 222Rn over Bilbao. The trajectory cluster and the TSA method show that the main airflow pathways are from the south, with small displacement, and the northeast, while the analysis of surface wind speed and direction indicates that the highest amplitudes of 222Rn concentrations are registered under the development of sea-land breezes. The PSCF method identified south-western and north-eastern areas highly contributing to the 222Rn concentration. These areas are confirmed by comparing with the radon flux map and the European map of uranium concentration in soil. The results have demonstrated the need in combining the analysis of local and regional/synoptic factors in explaining the origin and variability of 222Rn concentrations.

[EN] Ferritic-martensitic steels are candidate materials for blanket structural components of future thermonuclear fusion reactors. However, the tritium inventory that can be retained in different components of the reactor and its ability to migrate through the walls of any material may affect the correct operation of any fusion device. Therefore, the permeability of hydrogen isotopes through ferritic-martensitic steels, which depends on its metallurgical composition, becomes a key issue. The European Fusion Development Agreement (EFDA) supplied 9 Fe alloys with controlled chemical alloying element contents and microstructure. The main alloying elements were C, Cr and P and they appeared in various concentrations in the 9 alloys. They were experimentally analyzed by means of the gas evolution permeation technique with temperatures ranging from 423 K to 823 K and for high purity hydrogen loading pressures ranging from 5.0 x 102 Pa to 1.5 x 105 Pa. The transport regime turned out to be diffusive and it was studied in depth, so that the permeability of each alloy was characterized by an Arrhenius-type regression for the aforementioned temperature range. This work summarizes all the experimental measurements carried out for the permeability of hydrogen through the 9 alloys. It provides a quantification of the influence of the composition of the alloy on this transport parameter, posing different mathematical expressions for the variation of the permeability as a function of the contents of C, Cr and P.

186 p., La alta dependencia del sistema energético actual con respecto a los combustibles fósiles es un problema al que la humanidad debe hacer frente. Más allá de las consideraciones medioambientales que se puedan asociar a la combustión de los propios combustibles fósiles, las reservas de los mismos son finitas y a largo plazo se verán agotadas. Para afrontar esta situación se plantea el uso de la energía nuclear de fusión como opción tecnológica alternativa a medio plazo. En términos generales se espera que la fusión nuclear pueda suponer una fuente de energía masiva inagotable, limpia y segura.En este contexto el proyecto ITER pretende demostrar la viabilidad tecnológica de la fusión nuclear por confinamiento magnético mediante la construcción de un reactor de fusión que obtenga una potencia superior a la aportada para ponerlo en marcha. Uno de los elementos críticos de este tipo de reactores son las envolturas regeneradoras, a través de las que se debe extraer la energía generada por las reacciones de fusión y, a su vez, proporcionar todo el tritio necesario para mantener la reacción termonuclear durante la vida de la planta.Los materiales que constituirán los diferentes componentes de las futuras plantas de fusión estarán sujetos a la interacción con los isótopos de hidrógeno. El conocimiento de esta interacción resulta fundamental, sobre todo en las mencionadas envolturas regeneradoras, ya que condiciona la viabilidad de regeneración de tritio. Se debe recoger el tritio generado y transportarlo adecuadamente sin que se produzcan pérdidas sustanciales por difusión y absorción en el seno de dichos materiales, de manera que la gestión del combustible tritio se realice de manera eficiente.Todas las envolturas regeneradoras propuestas para ser ensayadas en ITER utilizarán un acero ferrítico-martensítico de baja activación neutrónica como material estructural. Resulta fundamental, por tanto, conocer los parámetros de transporte de los isótopos de hidrógeno en dichos aceros

Helburuak: Ikasmaterial hau Euskal Herriko Unibertsitateko (UPV/EHU) Bilboko Ingeniaritza Goi Eskola Teknikoan (IGET) Makina Hidraulikoak irakasgaian 2004-2005 ikasturtetik 2010-2011 ikasturtera bitartean proposatu diren azterketetako enuntziatuen bilduma bat da. Ariketa horietan, makina hidrauliko guztien artean, bereziki turbomakinak landu dira helburu hauekin: Industria mailan fluidoekin lan egiten duten instalazioen eta makinen kalkuluetan trebetasuna hartzea. Ponpaketa-instalazioetan ponpen aukeraketa egitea, funtzionamendu-puntuak zehaztea, lan-baldintza egokiak zeintzuk diren ulertzea eta ager daitezkeen arazoak aurreikustea. Elektrizitatea lortzeko erabiltzen diren turbina hidraulikoen kalkuluak lantzea: aukeraketa, dimentsionaketa, funtzionamendua, antzekotasuna eta abar. Norentzat: Ikasmaterial hau Ingeniaritza Industrialeko 5. mailako Fluidoen Instalazioak eta Makinak izeneko irakasgaian erabiltzeko aproposa da. Horrez gain, Ingeniaritza Industrialeko Hidraulikari dagokion espezialitatean bereziki eta baita beste alor batzuetan ere erabilgarria izan daiteke: Fluidoen Mekanika, Instalazio Hidraulikoak... Orokorrean, Makina Hidraulikoekin zerikusia duten gaiak lantzen dituen edozein ikaslerentzat prestatutako lana da., Liburu honetan atal hauek agertzen dira: 1.- Hitzaurrea, 2.- Ponpak 3.- Turbinak, 4.-Emaitzak