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Eggenstein-Leopoldshafen, Germany

Ionete E.I.,National RandD Institute for Cryogenics and Isotopic Technologies | Monea B.,National RandD Institute for Cryogenics and Isotopic Technologies | Plusczyk C.,Institute for Technical Physics | Ionete R.E.,National RandD Institute for Cryogenics and Isotopic Technologies
Fusion Engineering and Design | Year: 2013

This paper conducts an experiment and a three-dimensional (3D) modeling study for the absorption of hydrogen and deuterium on a storage tank with titanium sponge bed in order to simulate the real working conditions of a tritium storage system prior to tritium service. The 3D model is further numerically implemented and experimentally validated. The model is composed of an energy balance, mass balance and momentum balance and hydriding reaction kinetics. These differential equations are solved using finite element method. The experimental consisting in absorption of hydrogen and deuterium gas was made in batch made, under vacuum condition. Before absorption, an activation of the titanium bed was performed. A number of loading and releasing operations typically required in tritium handling loops were conducted using one bed containing a well determined quantity of titanium sponge. A comparison between theoretical results and experimental data has found that the gas was not uniformly absorbed on the metal bed volume. This work provides an important platform to understand the phenomena during tritium absorption on a titanium storage bed and the development of a real-time tritium storage control system. © 2013 Elsevier B.V. Source

Schlosser M.,Institute for Technical Physics | Fischer S.,Institute for Technical Physics | Hotzel M.,Institute for Nuclear Physics | Kafer W.,Institute for Nuclear Physics
Proceedings of the International School of Physics "Enrico Fermi" | Year: 2012

The aim of the Karlsruhe Tritium Neutrino experiment (KATRIN) is the direct (model-independent) measurement of the neutrino mass. For that purpose a windowless gaseous tritium source is used, with a tritium throughput of 40 g/day. In order to reach the design sensitivity of 0.2 eV/c 2 (90% C.L.) the key parameters of the tritium source, i.e. the gas inlet rate and the gas composition, have to be stabilized and monitored at the 0.1% level (1σ). Any small change of the tritium gas composition will manifest itself in non-negligible effects on the KATRIN measurements; therefore, Laser Raman spectroscopy (LARA) is the method of choice for the monitoring of the gas composition because it is a non-invasive and fast in-line measurement technique. In this paper, the requirements of KATRIN for statistical and systematical uncertainties of this method are discussed. An overview of the current performance of the LARA system with respect to precision will be given. In addition, two complementary approaches of intensity calibration are presented. © Società Italiana di Fisica. Source

Toigo V.,Consorzio RFX | Boilson D.,ITER Organization | Bonicelli T.,Fusion for Energy F4E | Piovan R.,Consorzio RFX | And 117 more authors.
Nuclear Fusion | Year: 2015

The ITER project requires additional heating by two neutral beam injectors, each accelerating to 1 MV a 40 A beam of negative deuterium ions, to deliver to the plasma a power of about 17 MW for one hour. As these requirements have never been experimentally met, it was recognized as necessary to setup a test facility, PRIMA (Padova Research on ITER Megavolt Accelerator), in Italy, including a full-size negative ion source, SPIDER, and a prototype of the whole ITER injector, MITICA, aiming to develop the heating injectors to be installed in ITER. This realization is made with the main contribution of the European Union, through the Joint Undertaking for ITER (F4E), the ITER Organization and Consorzio RFX which hosts the Test Facility. The Japanese and the Indian ITER Domestic Agencies (JADA and INDA) participate in the PRIMA enterprise; European laboratories, such as IPP-Garching, KIT-Karlsruhe, CCFE-Culham, CEA-Cadarache and others are also cooperating. Presently, the assembly of SPIDER is on-going and the MITICA design is being completed. The paper gives a general overview of the test facility and of the status of development of the MITICA and SPIDER main components at this important stage of the overall development; then it focuses on the latest and most critical issues, regarding both physics and technology, describing the identified solutions. © 2015 EURATOM. Source

Neumann H.,Institute for Technical Physics | Mayrhofer R.,RUAG RUAG Space GmbH | Richter T.,Institute for Technical Physics
IOP Conference Series: Materials Science and Engineering | Year: 2015

Complex, non-developable surfaces require a tailored multi-layer insulation (MLI) for lowest heat load. The most experiments showing the heat transfer through MLI are performed under quasi-ideal conditions determining the principle insulation quality. But the surface to be insulated in real cryostats implies feed-throughs and other non-developable surface parts. The thermal performance of MLI is degraded significantly at cutting points. To investigate this degrading effect a LN2-filled cylinder with a diameter of 219 mm and a length of 1820 mm was insulated with MLI and the heat load was measured by means of calorimetry. In addition the heat load to an insulated cylinder with eighteen branches was measured. Both cylinders have the same surface of 1.37 m2 for a comparison of the results. This article describes the experiments with different ways of tailoring the MLI for the cylinder with branches and discusses their results. It was shown that the cutting points at the branches have a significant degrading influence on the thermal performance of MLI. Source

Haas H.,Institute for Technical Physics | Day Chr.,Institute for Technical Physics | Herzog F.,Messer Group GmbH
AIP Conference Proceedings | Year: 2012

The Karlsruhe Institute of Technology (KIT) has been carrying out research and development in the field of vacuum cryopumps for nuclear fusion devices over the last decade. Together with the development activities also experience in the operation of the needed cryogenic systems necessary for such type of large scale cryopumps was collected. Due to the specific requirements of a large fusion device, such as ITER, the cryogenic distribution is based on gaseous helium at the needed temperature levels rather than liquid nitrogen or liquid helium. KIT has set up a large scale research facility, called TIMO-2, fully equipped with supercritical helium supply at large flow rates to be able to perform cryogenic tests of components under ITER-relevant conditions. During first test campaigns at TIMO-2 with a large scale model cryopump the ITER cryosorption vacuum pumping concept was successfully validated. After major refurbishments and upgrades, the TIMO-2 facility is now ready for the acceptance tests of the ITER torus cryopump. This paper describes the modified test facility TIMO-2 with particular attention to the available cryogenic supply at different temperature levels. The new 100 K helium supply facility will be described in detail. © 2012 American Institute of Physics. Source

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