Component Category: --Fuel pins
19 documents found
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Documentation of the SILOE experiments results (Experiment S2) Dokumentation der SILOE Ergebnisse (Versuch S2)
Glauner, W.;Plitz, HKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--1210 - German - 1977
Abstract: The performance during operation of a defective sodium cooled oxide fuel rod is to be determined. For this purpose, oxide fuel rods are provided with an artificial defect in a series of tests and operated for about two months each in a sodium loop of the SILOE reactor in Grenoble. The data and mode of LMFBR operating conditions, implying partial load and full load as well as the typically slow power cyclings. That means, that LOF and TOP behavior are not investigated. Three objectives were pursued in these tests: 1. Investigation into the behaviour of the defective fuel rod power, especially questions related to defect growth. 2. Development and verification of measuring methods allowing to detect defects. 3. Determination of fuel and fission gas release from the rod and their distribution and deposition in sodium systems. The first test (S2) was performed in 1976 with a fresh fuel rod. The results obtained on the three topics indicated above are reported
Key words: coolant loops;failed element detection;fission product release;fuel element failure;international cooperation;knk-2 reactor;reactor safety experiments;siloe reactor
R&D Category: -Failure detection
display the document: 34086307.pdf
Influence of fuel pin bowing on the temperature distribution in fuel pin cladding tubes in case of sodium cooling. Experimental results Einfluss der Stabverbiegung auf die Temperaturverteilung in Brennstabhuellrohren bei Natriumkuehlung - Experimentelle Ergebnisse -
Moeller, R.;Tschoeke, H.;Kolodziej, MKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.02.23P01D - German - 1978
Abstract: The influence of rod bowing on the local temperature distribution was measured with turbulent sodium flow in the cladding tubes of a 19-rod bundle mock-up of the SNR 300 Mark Ia fuel element. Such measurements have been carried out for the first time. The results presented in this report are part 1 of the experimental evaluation not yet completed. The major results are: 1. When a rod on the first ring gets deformed towards a neighbour on the second ring with a gap reduction from the nominal value of 100 % down to 20 %, the maximum azimuthal temperature difference of the outer rod increases by about 60 %. 2. The maximum azimuthal temperature difference of a rod on the first ring increases by a factor of 2, if it is approached by a neighbour on the same ring. 3. The reduction in cross section of a subchannel by rod bowing results only locally in distinct temperature rises, i.e. in the adjacent cladding tubes. Rods of the next but one row are no more subject to noticeable changes in temperature
Key words: bowing;deformation;design;fuel assemblies;knk-2 reactor;sodium;temperature distribution;testing;thermal hydraulics;turbulent flow
R&D Category: Thermo mechanical properties of systems during normal and beyond-design operating regimes and materials science
display the document: 34086298.pdf
Detection of the first fuel pin failure in KNK II Detektion des ersten defekten Brennstabs in der KNK II
Hoffmann, G.;Jacobi, S.;Jonatzke, O.;Letz, K.D.;Schmitz, GKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.02.17P22A - German - 1979
Abstract: This report describes the detection of the first failed fuel pin in KNK II on April 1st, 1979. The DND signals of the background of both DND monitors installed near the main sodium pipes are compared with the signals after the beginning of the failure. The free fuel surface was estimated at about 1 mm''2 from the signal amplitudes. Immediately after the beginning of the failure the online-gamma-spectrometer started a special measurement, this spectrum is also compared with the background spectrum
Key words: defects;delayed neutron analysis;failed element detection;fuel element failure;fuel pins;gamma spectroscopy;knk-2 reactor;neutron detection;on-line control systems;reactor safety
R&D Category: -Failure detection
display the document: 34086280.pdf
Technical specifications for the fuel pin of the carbide element in the test zone of KNK II/2 Technische Spezifikationen fuer den Brennstab des Karbidelementes der Testzone von KNK II/2
Freund, D.;Jacobi, O.;Ritzhaupt-Kleissl, H.-J.;Steiner, HKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.01.16P66A - German - 1981
Abstract: Uranium-Plutonium-Mixed Carbide fuel is investigated as an alternative fast breeder fuel to the actual mixed oxide because of some special properties. As a completion of the carbide irradiation program of KfK/PSB the operation of a 19-pin bundle in KNK II was foreseen. On the basis of the national and international experience a reference concept was defined for that purpose. Among others, the following data were fixed: pin diameter 8.5 mm, clad thickness 0.55 mm, fuel smear density 75 %, He-bonding, maximum nominal linear rating 800 W/cm. The present report contains the specifications for the fuel pin including fissile and fertile materials as well as for structural materials. The fuel pins fabricated according to these specifications will guarantee the expected operational behavior
Key words: design;fertile materials;fissile materials;fuel assemblies;fuel pins;knk-2 reactor;mixed carbide fuels;specifications
R&D Category: any or undefined
display the document: 34087771.pdf
Dismantling and post-irradiation examination of the two first defective fuel pins of the KNK-II. Die Zerlegung und Nachuntersuchung des ersten und zweiten defektiven KNK II-Brennelemente
Enderlein, H.;Kathol, W. (Kernforschungszentrum Karlsruhe G.m.b.H. (Germany, F.R.). Hauptabteilung Kerntechnische Betriebe;Kernforschungszentrum Karlsruhe G.m.b.H. (Germany, F.R.). Projekt Schneller Brueter)KFK--3278 - German - 1982
Abstract: The report contained the dismantling and the post irradiation examination of the two first defective fuel elements of the KNK II-reactor. The construction of the dismantling device and the process of dismantling of the fuel elements are described. The main aim of the examination of the fuel pins is to find the defective pin and to establish the cause of the pin damage. The most important steps for this are shown, also a few of the results. Finally improvements to a planned second dismantling device are described. (orig.)
Key words: failed element detection;fuel assemblies;fuel assembly dismantling;fuel element failure;fuel pins;knk-2 reactor;post-irradiation examination
R&D Category: Safety aspects
display the document: 13696679.pdf
Reprocessing of KNK II reactor fuel rods at the MILLI plant. Wiederaufarbeitung von KNK II-Brennstaeben in der MILLI
Bleyl, H.J.;Ochsenfeld, W. (Kernforschungszentrum Karlsruhe G.m.b.H. (Germany, F.R.). Inst. fuer Heisse Chemie)KFK--3290 - German - 1982
Abstract: To demonstrate a closed fuel cycle with recycling of uranium and plutonium, a KNK II reactor fuel element with a burn-up of 1.3% after a decay period of about 23 months has been reprocessed in the MILLI laboratory extraction plant according to the PUREX process. Three extraction cycles have been used. First, a coordination cycle with uranium and plutonium as end products. Secondly, a uranium/plutonium separation cycle with the plutonium fraction as end product, and thirdly a remote-controlled decontamination cycle for the uranium end product. The uranium or plutonium end products have been used for refabrication. Details of reprocessing are described, and the operating results of this process are reported. (RB)
Key words: decontamination;efficiency;knk-2 reactor;laboratory equipment;mixed oxide fuels;plutonium;purex process;solvent extraction;uranium
R&D Category: any or undefined
display the document: 13713539.pdf
Design report for core assemblies KNK II/2: Fuel pins with high density fuel Auslegungsbericht fuer Kernelemente KNK II/2: Brennstaebe mit hoher Dichte
Fenneker, KINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.04214.9 - German - 1982
Abstract: The design report describes the mechanical and thermal behavior of fuel pins with higher fuel density (94 - 95.5 %) in the second core of KNK II with a residence time of 455 equivalent full-power days. The pins will be loaded into the central position and one position on the first assembly ring. The tasks and the design of the fuel pins are described, and the criteria, methods and results for the design of fuel pins with high density are presented. The admissibility of the loadings for cladding and fuel, to be expected during the operation in KNK II/2, is demonstrated
Key words: burnup extension;calculation methods;cladding;density;design;fuel assemblies;fuel pellets;fuel pins;knk-2 reactor
R&D Category: Reactor physics
display the document: 34085704.pdf
KNK II on-line gamma spectrometer: Documentation of measurement results of the defected pin experiments from 28.10.1981 till 22.6.1982 KNK II on-line -Gammaspektrometer: Messwert-Dokumentation der Defektstabexperimente vom 28.10.1981 bis 22.6.1982
Hoffmann, G.;Letz, K.DKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.02.17P82A - German - 1982
Abstract: From October 28, 1981 till June 22, 1982 three experiments with different artificially defected pins have been performed at KNK II. The paper shows the measured values collected by the on-line gamma spectroscope during these experiments. For comparison, the results of background measurements from July 5 to August 4, 1982 are added
Key words: cover gas;failed element monitors;fuel element failure;fuel pins;gamma spectroscopy;knk-2 reactor;on-line systems;reactor safety;testing
R&D Category: -Failure and failure propagation mechanisms
display the document: 34086287.pdf
Design Report for a 19-pin carbide test-bundle in a ring-subassembly of the test zone of KNK II/2 Auslegungsbericht fuer ein 19-Stab Karbidtestbuendel in einem Ringelement auf der Kranzposition 201 der Testzone KNK II/2
Haefner, H.EKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.01.16P83A - German - 1982
Abstract: This report describes a 19-rod carbide test bundle in an annular oxide ring element placed at the position 201 of the test zone in the second core of KNK II as well as its behavior during the period of operation. The selected fuel rod concept includes low pellet density and a relatively large gap width as well as helium bonding between fuel and cladding. Characteristic design and operation data are: rod diameter 8.5 mm, pellet diameter 7.0 mm, maximum nominal linear rating 800 W/cm, maximum nominal burnup 70 MWd/kgHM. This report exclusively deals with the carbide test bundle and its individual components. It describes methods, criteria and results concerning the design. The annular carrier element with its head and foot is treated in a separate report. The loadability of the test bundle and its individual components is demonstrated by generally valid standards for strength criteria
Key words: annular fuel elements;burnup;design;fuel assemblies;interstitial helium generation;knk-2 reactor;mixed carbide fuels
R&D Category: any or undefined
display the document: 34087772.pdf
Steady-state irradiation experiments. Stationaere Bestrahlungsexperimente
Geithoff, D. (Kernforschungszentrum Karlsruhe G.m.b.H. (Germany, F.R.). Inst. fuer Material- und Festkoerperforschung 3 - Teilinstitut Brennelemente)KFK--3505 - German - 1983
Abstract: This paper describes the steady-state irradiation experiments DFR-350, RAPSODIE-I and DFR-455 to be milestones in the development of the SNR Mk Ia fuel rod concept and also a number of relevant results. For the two defective fuel elements from the KNK-2 reactor, in particular for the BE 202 IA, the status of the fuel rods is described on the basis of results obtained at the various stages of post-irradiation examination. The comparison of these results with those from previous experiments shows the value of such results for these rods. Thus the fuel rod behaviour in different circumstances is evaluated in qualitative terms. (orig.)
Key words: fuel element failure;fuel pins;irradiation capsules;irradiation devices;irradiation procedures;knk-2 reactor;post-irradiation examination
R&D Category: Thermo mechanical properties of systems during normal and beyond-design operating regimes and materials science
display the document: 15028668.pdf
Fuel assembly NY-308 Compilation of the fuel and fuel pin fabrication data from the T264 data bank system BESEX Das KNK II/2 Brennelement NY-308 Zusammenstellung der Brennstoff- und Brennstabfertigungs-Daten aus dem T264-Datenbanksystem BESEX
Patzer, GINTERATOM GmbH, Bergisch Gladbach (Germany)
IA--54.06863.8 - German - 1986
Abstract: The fuel assembly NY-308 will be the first assembly of the second core of KNK II to undergo post-irradiation examinations. It had reached a residence time of 273.5 equivalent full-power days. For the planning of the post-irradiation examinations and as support for a valuation of their results, the data of the fuel and fuel pin fabrication are presented in this report on the basis of the data bank system BESEX. The presentation is given in form of assembly cross-sections and in different tables, which are compiled according to different view points
Key words: burnup;data compilation;fissile materials;fuel assemblies;fuel pins;knk-2 reactor;post-irradiation examination
R&D Category: Reactor physics
display the document: 34085712.pdf
International experience with the bundle behavior of fuel elements of sodium cooled reactors. Derivation of a figure of merit for the judgement of fuel pin bundle parameters with respect to abrasion due to thermoelastic pin-pin interaction Internationaler Erfahrungsstand zum Buendelverhalten von SNR-Brennelementen. Richtgroesse zur vergleichenden Beurteilung der Buendelparameter bezueglich Verschleiss infolge thermoelastischer Stab/Stab-Wechselwirkung
Toebbe, HINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.07375.3 - German - 1987
Abstract: The report describes the status of experience with respect to the abrasion behavior of bundles in standard fuel elements and test elements with wire or grid spacing in the reactors Rapsodie fortissimo, Phenix, DFR, PFR, EBR-II, FFTF, JOYO and KNK II. With the help of simple considerations concerning thermoelastic pin-pin interactions a figure of merit is deduced from the different bundle parameters, which allows a comparative judgement of the parameters of different bundle concepts
Key words: abrasion;dfr reactor;ebr-2 reactor;fuel assemblies;fuel pins;international cooperation;joyo reactor;knk-2 reactor;performance;pfr reactor;phenix reactor;rapsodie reactor;spacers;thermoelasticity
R&D Category: Thermo mechanical properties of systems during normal and beyond-design operating regimes and materials science
display the document: 34085726.pdf
Influence of deposits on fuel pins and pin spacers of the fuel subassemblies on the temperature increase distribution of the fuel subassemblies in KNK II/2 Einfluss von Ablagerungen auf den Brennstaeben und Abstandshaltern der Brennelemente auf die Aufwaermspannenverteilung der Brennelemente der KNK II/2
Heinecke, JINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.07431.9 - German - 1987
Abstract: Post-irradiation examinations of two fuel subassemblies of KNK II/2 have shown deposits of impurities of the sodium on the fuel pins and the pin spacers. It is shown in the report, that these deposits can be the origin of the differences between the measured and the pre-calculated temperature increases of the fuel subassemblies
Key words: deposits;fuel assemblies;knk-2 reactor;post-irradiation examination;sodium;spacers;temperature distribution;thermal hydraulics
R&D Category: Thermo mechanical properties of systems during normal and beyond-design operating regimes and materials science
display the document: 34085728.pdf
Fuel pin failures in the second core of KNK II, Experiences and valuation Brennstabschaeden im zweiten Kern der KNK II, Erfahrungen und Bewertung
Kernforschungszentrum Karlsruhe GmbH (Germany), Kernkraftwerk-Betriebsgesellschaft mbH (DE), INTERATOM GmbH, Bergisch Gladbach (DE)IA--75.16997.3 - German - 1987
Abstract: The second core of KNK II has reached until now a residence time of 432 equivalent full-power days (efpd) within the licensed 455 efpd. A license application for a residence time extension to 720 efpd has been supplied. Four fuel assemblies had been unloaded after the occurrence of DND-signals. The post-irradiation examinations of the test assembly NY-308 and of the driver assembly NW-302 showed wear marks on the cladding surface in the area of the upper pin spacer. One fuel pin of the test assembly NY-308 and two fuel pins of the driver assembly NW-302 experienced a cladding failure in the area of maximum interaction with the spacers. The findings show, that the wear marks have a systematic origin, but the failures do occur only stochastically on single pins. It is proved, that no safety related problems for the nominal operation and for accidental situations have to be expected even after 720 efpd. It is ensured, that the plant can be operated within its design and licensing limits
Key words: cladding;delayed neutron analysis;fuel element failure;knk-2 reactor;neutron detection;post-irradiation examination;reactor operation;risk assessment;wear
R&D Category: -Failure and failure propagation mechanisms
display the document: 34087398.pdf
Influence of fabrication parameters on the operational behavior of fuel pins Einfluss von Herstellungs-Parametern auf das Betriebsverhalten von Brennstaeben
Ritzhaupt-Kleissl, H.-J.;Elbel, H.;Heck, MKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.01.02P17F - German - 1987
Abstract: During the last recent years investigations on structure and properties of high dense FBR fuel types were performed. One of the most important parameters is the thermal conductivity. As could be observed, microcracks in the material can influence the thermal conductivity by up to about 20 %. The occurrence of these microcracks is related to local stoichiometry changes in the fuel. By pre-test modelling calculations the influence of the following fuel fabrication parameters on the fuel pin behavior was studied: fuel stoichiometry, pellet diameter, purity of the backfill gas and sintering atmosphere. These calculations show, that a reduction of fuel stoichiometry from O/M=1.97 to 1.93 results in a centerline temperature increase of about 8 %. The influence of a change in backfill gas composition from 90 % He to 50 % He is less pronounced. A larger pellet diameter leads, generally, to higher centerline temperatures during operation
Key words: cracks;fabrication;fuel elements;irradiation;knk-2 reactor;mechanical properties;microstructure;performance;sintering;stoichiometry;thermal conductivity
R&D Category: Thermo mechanical properties of systems during normal and beyond-design operating regimes and materials science
display the document: 34087753.pdf
Experiments on thermohydraulically induced fuel rod oscillations in a sodium flow. THIBO-Experiments Experimente zu thermohydraulisch induzierten Brennstab-Oszillationen im Natrium Strom. THIBO-Experimente
Bojarsky, E;Deckers, H.;Lehning, H.;Piel, D.;Reiser, H.;Schmidt, LKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.11.12P06B - German - 1989
Abstract: The fuel rod claddings of the sodium cooled fast reactor KNK II showed damage in the form of wear marks and cracks. There is some evidence indicating that this damage is caused not by hydraulically induced vibrations but by low-frequency rod bowing due to the joint impacts of sodium heating and sodium flow. In order to investigate this supposed behavior of fuel pins, the THIBO (standing for thermohydraulically induced fuel pin oscillations) experiments have been performed in the sodium loop of the IMF III institute since November 1987 with an electrically heated test pin in an annular channel. These experiments have so far been successful inasmuch as it has been possible to generate under given conditions the anticipated variations in coolant channel temperatures and the periodical movements of the test pin corresponding to them, and to influence them by variation of operating parameters. Following a short description of the test facility, the test program as well as the essential test results are contained in the report
Key words: bowing;coolant loops;fuel pins;fuel rods;knk-2 reactor;mechanical vibrations;performance testing;sodium;thermal hydraulics
R&D Category: Thermo hydraulics in all operating, shut-down and accident regimes
display the document: 34086305.pdf
Synthesis Report on the understanding of failed LMFBR fuel element performance Zusammenfassender Bericht zum Verstaendnis des Verhaltens von LMFBR Brennstabfehlern
Plitz, H.;Bagley, K.;Harbourne, BKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.11.05P37B - German - 1990
Abstract: In the coarse of LMFBR operation fuel element failures cannot entirely be avoided as experienced during the operation of PFR, PHENIX and KNK II, where 44 failed fuel elements have been registered between 1978 and 1989. In earlier irradiations, post irradiation examinations showed mixed oxide pin diameter increases up to pin pitch distance, urging to stress reactor safety questions on the potential of fuel pin failure propagation within pin bundles. The chemical interaction of sodium with mixed oxide fuel is regarded to be the key for the understanding of failed fuel behavior. Valuable results on the failed fuel pin behavior during operation were obtained from the SILOE sodium loop test. Based on the bulk of experience with the detection of fuel pin failures, with the continued operation and with the handling of failed pins respectively elements, one can state: 1. All fuel pin failures have been detected securely in time and have been located. 2. Small defects are developing slowly. 3. Even large defects at end-of-life pins resulted in limited fuel loss. 4. Clad failures behave benign in main aspects. 5. The chemical interaction of sodium with mixed oxide is an important factor in the behavior of failed fuel pins, especially at high burnup. 6. Despite different pin designs and different operation conditions, on the basis of 44 failed elements in PFR, PHENIX and KNK II no pin-to-pin propagation was observed and fuel release was rather low, often not detectable. 7. In no case hazard conditions affecting reactor safety have been experienced
Key words: burnup;defects;failures;fast reactors;fuel element failure;fuel-coolant interactions;international cooperation;knk-2 reactor;lmfbr type reactors;performance testing;risk assessment;sodium
R&D Category: -Failure and failure propagation mechanisms
display the document: 34086303.pdf
IAMBUS, a computer code for the design and performance prediction of fast breeder fuel rods
Toebbe, HINTERATOM GmbH, Bergisch Gladbach (Germany)
IA--54.08000.1 - English - 1990
Abstract: IAMBUS is a computer code for the thermal and mechanical design, in-pile performance prediction and post-irradiation analysis of fast breeder fuel rods. The code deals with steady, non-steady and transient operating conditions and enables to predict in-pile behavior of fuel rods in power reactors as well as in experimental rigs. Great effort went into the development of a realistic account of non-steady fuel rod operating conditions. The main emphasis is placed on characterizing the mechanical interaction taking place between the cladding tube and the fuel as a result of contact pressure and friction forces, with due consideration of axial and radial crack configuration within the fuel as well as the gradual transition at the elastic/plastic interface in respect to fuel behavior. IAMBUS can be readily adapted to various fuel and cladding materials. The specific models and material correlations of the reference version deal with the actual in-pile behavior and physical properties of the KNK II and SNR 300 related fuel rod design, confirmed by comparison of the fuel performance model with post-irradiation data. The comparison comprises steady, non-steady and transient irradiation experiments within the German/Belgian fuel rod irradiation program. The code is further validated by comparison of model predictions with post-irradiation data of standard fuel and breeder rods of Phenix and PFR as well as selected LWR fuel rods in non-steady operating conditions
Key words: cracks;friction;fuel assemblies;fuel rods;fuel-cladding interactions;i codes;international cooperation;knk-2 reactor;mechanical properties;snr reactor;steady-state conditions;thermal analysis;transients
R&D Category: -Analytic and numeric methods
display the document: 34087385.pdf
THIBO experiments. Experiments on thermohydraulically induced fuel rod oscillations in a sodium flow. Final report
Bojarsky, E.;Deckers, H.;Lehning, H.;Piel, D.;Reiser, H.;Schmidt, LKernforschungszentrum Karlsruhe GmbH (Germany). Inst. fuer Materialforschung;Kernforschungszentrum Karlsruhe GmbH (Germany). Projekt Nukleare Sicherheitsforschung
KFK--4798 - English - 1991
Abstract: The KNK II in Karlsruhe experienced fuel element damage which could not be traced back to hydraulically excited vibrations. Instead, some indications pointed to low-frequency fuel rod oscillations caused by temperature differences over the circumference of the fuel rod as a result of the high specific rod power and the clearance of fuel rods in their spacers. In 1988, specific experiments were started in the sodium loop of the IMF III to investigate this phenomenon (THIBO experiments). The rod movements were made visible and detected in a reproducible way. In 1989, another series of tests, THIBO II, have been run in a second test section. In this case, the cooling channel area was reduced so much that the thermohydraulic conditions very closely approximate those existing in the KNK II reactor. The experiments have shown that fuel rods may start moving already at relatively low sodium temperature increase and low partial loads, respectively, even if the rod clearance in the spacer was set to realistically low levels. (orig.)
Key words: cracks;flow rate;fuel rods;hydraulics;image scanners;in pile loops;knk-2 reactor;mass transfer;oscillations;sodium;spacers;temperature distribution;thermocouples;thermodynamics
R&D Category: Reactor physics
display the document: 23002234.pdf