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Sample records for 2mw triga mark

  1. Evaluation Of Reactor Coolant System Of Design Of Bandung TRIGA Mark II 2 MW Reactor

    An evaluation of reactor coolant system of Bandung TRIGA Mark II has been carried out. The evaluation is conducted for primary and secondary system, both for steady state and transient conditions. The evaluation is based on the analysis results done by the operator. In the steady state (i.e. normal operation), the maximum temperature of fuel element is 569.7C. A series of analysis covering various accident scenarios of LOPA and LOCA shows that the coolant system and ECCS able to maintain the fuel temperature less then 970C, then the fuel integrity is kept safe. However, the detail analysis using validated codes is still needed to support the actual safety analysis

  2. Tank Design Evaluation Of TRIGA Mark II Reactor For 2 MW Power

    . Design calculation, safety factor choosing, and welding procedure on tank design of Bandung nuclear reactor for 2 MW power have been evaluated. For design calculation, the evaluation has especially done based on material strength input which was used on tank thickness calculation. Evaluation on safety factor choosing has been done by comparing the result of final calculation after inputting the value of safety factor to the physics condition will be occurred. On welding procedure, the evaluation has been carried to see the chance will be occurred if the excising design followed. From this evaluation, it can be concluded that the calculation just done to meet the result of the calculation to the thickness of material has been excised so it can be assumed as proper material of tank reactor

  3. Benchmark analysis of the 2MW TRIGA MARK II Moroccan research reactor using the MCNP code and the latest nuclear data libraries

    This study deals with the neutronic analysis of the 2MW TRIGA MARK II Moroccan research reactor. The reactor was commissioned at Centre des Etudes Nucleaires de la Maamora (CENM) and it went critical on May 2, 2007. The 3-D continuous energy Monte Carlo code MCNP5 was used to develop a full model of the TRIGA reactor, using the maximum details allowed by the constructor General Atomics of USA. Continuous energy cross section data from the more recent nuclear data evaluations (ENDF/B-VI.8, ENDF/B-VII.0, JEFF-3.1, and JENDL-3.3) as well as S(α, β) thermal neutron scattering functions distributed with the MCNP code were used. The cross section libraries were generated by using the NJOY99 system updated to its more recent patch file 'up259'. The consistency and accuracy of both Monte Carlo simulation and neutron transport physics were established by benchmarking the TRIGA experiments. (author)

  4. The study of time-dependent neutronics parameters of the 2MW TRIGA Mark II Moroccan research reactor using BUCAL1 computer code

    The 2-MW TRIGA MARK II research reactor at Centre National de l'Energie, des Sciences et des Techniques Nucleaires (CNESTEN) achieved initial criticality on May 2, 2007 with 71 fuel elements. The reactor is designed to effectively implement the various fields of basic nuclear research, manpower and training and production of radioisotopes for their use in agriculture, industry and medicine. This work aims to study the time-dependent neutronics parameters of the TRIGA reactor for elaborating and planning of an in-core fuel management strategy to maximize the utilization of the TRIGA fluxes, using a new elaborated burnup computer code called 'BUCAL1'. The code can be used to aid in analysis, prediction, and optimization of fuel burnup performance in a nuclear reactor. It was developed to incorporate the neutron absorption tally/reaction information generated directly by MCNP5 code in the calculation of fissioned or neutron-transmuted isotopes for multi-fueled regions. The use of Monte Carlo method and punctual cross section data characterizing the MCNP code allows an accurate simulation of neutron life cycle in the reactor, and the integration of data on the entire energy spectrum, thus a more accurate estimation of results than deterministic code can do. Also, for the purpose of this study, a full-model of the TRIGA reactor was developed using the MCNP5 code. The validation of the MCNP model of the TRIGA reactor was made by benchmarking the reactivity experiments. (author)

  5. TRIGA Mark II benchmark experiment

    Experimental results of pulse parameters and control rod worth measurements at TRIGA Mark 2 reactor in Ljubljana are presented. The measurements were performed with a completely fresh, uniform, and compact core. Only standard fuel elements with 12 wt% uranium were used. Special efforts were made to get reliable and accurate results at well-defined experimental conditions, and it is proposed to use the results as a benchmark test case for TRIGA reactors

  6. TRIGA Mark II benchmark experiment

    The experimental results of startup tests after reconstruction and modification of the TRIGA Mark II reactor in Ljubljana are presented. The experiments were performed with a completely fresh, compact, and uniform core. The operating conditions were well defined and controlled, so that the results can be used as a benchmark test case for TRIGA reactor calculations. Both steady-state and pulse mode operation were tested. In this paper, the following steady-state experiments are treated: critical core and excess reactivity, control rod worths, fuel element reactivity worth distribution, fuel temperature distribution, and fuel temperature reactivity coefficient

  7. The Neutronic And Power Distribution Calculations For Triga 2 MW Reactor Using WIMS-D/4 And Citation Codes

    . The neutronic calculation has been carried out for TRIGA 2 MW reactor. These included criticality flux and power distributions. Computer code Citation which solves 7-groups, 3-dimensional hexagonal geometry has been used. The multi groups-cross-section is generated by the WIMS-D/4 code.This 7-group-39x39x38-mesh-points problem takes about 90 minutes on the Pentium-133 MHz PC. The calculation of the initial core of TRIGA 2 MW reactor shows that the excess reactivity of the core is 7,8% and the thermal fluxes in the irradiation positions are between 1.0-2.9*1013n cm-2s-1. The results are about 10% deviate from those calculated by General Atomics. In the initial core, the highest power is produced in the C-9 position. The fuel element in this position produces 30.7 k W thermal power

  8. TRIGA Mark-II, III reactor operation

    TRIGA Mark-II reactor has been primarily utilized as usual for the fundamental reactor experiments for university students. The annual operating time is 1,100 hours and the gross thermal output is 17,159 KWH, having consumed 0.88g of U-235. The reconstuction work for the control console of this reactor is now in progress and will be completed in early part of 1982. TRIGA Mark-III reactor has been operated mainly for radioisotope production, test pin irradiation and activation analysis, etc., as well as solid state physics experiments using the beamports. The annual operatino. time is amounted to 3,530 hours being the longest since the beginning of its criticality, and the gross thermal output is 4,113,013 KWH, whereas the U-235 consumption is estimated at 212.82 g. 462 samples were irradiated to produce 9 kinds of radioisotopes. In order to carry out the test pin irradiation experiment, the core configuration of TRIGA Mark-III was changed by loadinq 6 fresh fuels at G-ring as of July 1981 and a new irradiation facility consisting of 14 tubes was manufactured in place of Rotary Specimen Rack. Then 7 kinds of physics experiments were performed over a two week period to scrutinize the chanaed core characteristics. In addition, the present TRIGA Mark-III reactor fuel storage tank was enlarged and the distilled water production facility was renewed to improve its production efficiency. (Author)

  9. Utilization of Slovenian TRIGA Mark II reactor

    TRIGA Mark II research reactor at the Jozef Stefan Institute [JSI] is extensively used for various applications, such as: irradiation of various samples, training and education, verification and validation of nuclear data and computer codes, testing and development of experimental equipment used for core physics tests at a nuclear power plant. The paper briefly describes the aforementioned activities and shows that even such small reactors are still indispensable in nuclear science and technology. (author)

  10. Triga Mark III Reactor in paleotemperatures determination

    The Triga Mark III reactor produces neutron fluxes which are used to irradiate geologic specimens with age estimation purposes. Irradiation produces radioactive nucleus in the sample as well as: 39 Ar used in the age estimation 40 Ar/39 Ar ratio, and fission fragments for the age estimation by fission tracks detection. This document presents the basis for both methods, as well as the attained results, and has the purpose to perform joint experimentation in order to extend the usefulness of the method to paleotemperature determination. A brief comment about the associated problematic of the sample irradiation is made

  11. Decontamination of TRIGA Mark II reactor, Indonesia

    The TRIGA Mark II Reactor in the Centre for Research and Development Nuclear Technique Bandung has been partially decommissioned as part of an upgrading project. The upgrading project was carried out from 1995 to 2000 and is being commissioned in 2001. The decommissioning portion of the project included disassembly of some components of the reactor core, producing contaminated material. This contaminated material (grid plate, reflector, thermal column, heat exchanger and pipe) will be sent to the Decontamination Facility at the Radioactive Waste Management Development Centre. (author)

  12. Decommissioning of TRIGA Mark II type reactor

    The first research reactor in Korea, KRR 1, is a TRIGA Mark II type with open pool and fixed core. Its power was 100 kWth at its construction and it was upgraded to 250 kWth. Its construction was started in 1957. The first criticality was reached in 1962 and it had been operated for 36,000 hours. The second reactor, KRR 2, is a TRIGA Mark III type with open pool and movable core. These reactors were shut down in 1995, and the decision was made to decommission both reactors. The aim of the decommissioning activities is to decommission the KRR 2 reactor and decontaminate the residual building structures and site, and to release them as unrestricted areas. The KRR 1 reactor was decided to be preserve as a historical monument. A project was launched for the decommissioning of these reactors in 1997, and approved by the regulatory body in 2000. A total budget for the project was 20.0 million US dollars. It was anticipated that this project would be completed and the site turned over to KEPCO by 2010. However, it was discovered that the pool water of the KRR 1 reactor was leaked into the environment in 2009. As a result, preservation of the KRR 1 reactor as a monument had to be reviewed, and it was decided to fully decommission the KRR 1 reactor. Dismantling of the KRR 1 reactor takes place from 2011 to 2014 with a budget of 3.25 million US dollars. The scope of the work includes licensing of the decommissioning plan change, removal of pool internals including the reactor core, removal of the thermal and thermalizing columns, removal of beam port tubes and the aluminum liner in the reactor tank, removal of the radioactive concrete (the entire concrete structure will not be demolished), sorting the radioactive waste (concrete and soil) and conditioning the radioactive waste for final disposal, and final statuses of the survey and free release of the site and building, and turning over the site to KEPCO. In this paper, the current status of the TRIGA Mark-II type reactor

  13. Decommissioning of TRIGA Mark II type reactor

    Hwang, Dooseong; Jeong, Gyeonghwan; Moon, Jeikwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-10-15

    The first research reactor in Korea, KRR 1, is a TRIGA Mark II type with open pool and fixed core. Its power was 100 kWth at its construction and it was upgraded to 250 kWth. Its construction was started in 1957. The first criticality was reached in 1962 and it had been operated for 36,000 hours. The second reactor, KRR 2, is a TRIGA Mark III type with open pool and movable core. These reactors were shut down in 1995, and the decision was made to decommission both reactors. The aim of the decommissioning activities is to decommission the KRR 2 reactor and decontaminate the residual building structures and site, and to release them as unrestricted areas. The KRR 1 reactor was decided to be preserve as a historical monument. A project was launched for the decommissioning of these reactors in 1997, and approved by the regulatory body in 2000. A total budget for the project was 20.0 million US dollars. It was anticipated that this project would be completed and the site turned over to KEPCO by 2010. However, it was discovered that the pool water of the KRR 1 reactor was leaked into the environment in 2009. As a result, preservation of the KRR 1 reactor as a monument had to be reviewed, and it was decided to fully decommission the KRR 1 reactor. Dismantling of the KRR 1 reactor takes place from 2011 to 2014 with a budget of 3.25 million US dollars. The scope of the work includes licensing of the decommissioning plan change, removal of pool internals including the reactor core, removal of the thermal and thermalizing columns, removal of beam port tubes and the aluminum liner in the reactor tank, removal of the radioactive concrete (the entire concrete structure will not be demolished), sorting the radioactive waste (concrete and soil) and conditioning the radioactive waste for final disposal, and final statuses of the survey and free release of the site and building, and turning over the site to KEPCO. In this paper, the current status of the TRIGA Mark-II type reactor

  14. Decommissioning plan for the TRIGA mark-3

    TRIGA Mark-III (KRR-2) is the second research reactor in Korea. Construction of KRR-2 was started in 1969 and first criticality was achieved in 1972. After 24 years operation, KRR-2 has stopped its operation at the end of 1995 due to normal operation of HANARO. KRR-2 was then decided to decommission in 1996 by government. Decontamination and decommissioning (D and D) will be conducted in accordance with domestic laws and international regulations. Selected method of D and D will be devoted to protect workers and environment and to minimize radioactive wastes produced. The major D and D work will be conducted safely by using conventional industrial equipment because of relatively low radioactivity and contamination in the facility. When removing activated concrete from reactor pool, it will be installed a temporary containment and ventilation system. In this paper, structure of KRR-2 and method of D and D in each step are presented and discussed

  15. Decommissioning plan for TRIGA Mark-2

    Park, Seung Kook; Lee, B.J.

    1999-04-01

    Korea Research Reactor 1(KRR 1; TRIGA Mark-2) is the first reactor in Korea, but its decommissioning is underway due to its life. In this paper, presenting the reason and object of decommissioning KRR 1, then describing reactor structure and survey result of the facility, activation and contamination status around reactor and nearby equipment and vicinity. Estimating dose rate was evaluated for every work stage. Those of survey, evaluation and radiological status were considered to determine the safe and reasonable decommissioning methods. The order of decommissioning works are divided by section to minimize possible hazard. Proposed decommissioning plan is based on hazard and operability study to protect workers and residents from radiation expose. (author). 12 refs., 5 tabs., 6 figs.

  16. Decommissioning plan for TRIGA Mark-2

    Korea Research Reactor 1(KRR 1; TRIGA Mark-2) is the first reactor in Korea, but its decommissioning is underway due to its life. In this paper, presenting the reason and object of decommissioning KRR 1, then describing reactor structure and survey result of the facility, activation and contamination status around reactor and nearby equipment and vicinity. Estimating dose rate was evaluated for every work stage. Those of survey, evaluation and radiological status were considered to determine the safe and reasonable decommissioning methods. The order of decommissioning works are divided by section to minimize possible hazard. Proposed decommissioning plan is based on hazard and operability study to protect workers and residents from radiation expose. (author). 12 refs., 5 tabs., 6 figs

  17. TRIGA Mark-III reactor dismantling program

    The activation assessment of the main parts of the TRIGA Mark-III (KRR-2) was estimated to effectively dismantle the activated and contaminated areas. All of the method and the order for decommissioning the KRR-2 have been chosen as a result of the examination of the physical structure and radiological conditions of the reactor component. These decommissioning methods and orders were reviewed as part of the Hazard and Operability (HAZOP) studies for the project. Radiological assessment is also done to protect the workers and the environment from the dismantling work. License documents were submitted to the Ministry of Science and Technology (MOST) at the end of 1998. Practical work of the D and D will start at the end of 1999 once the government issues the license. Radiation protection plan was also set up to control the workers and environment. This paper summarized the main lines of those studies. (author)

  18. Planned Scientific programs around the Triga Mark 2 Reactor

    Full text: Nuclear techniques have been introduced to Morocco since the sixties. After the energy crisis of 1973, Morocco decides to create the National Center for Energy Sciences and Nuclear Techniques (CNESTEN) under the supervision of the Ministry of high Education and Research, with a research commercial and support vocation. CNESTEN is in charge of promoting nuclear application, to act as technical support for the authorities and to prepare the technological basis for nuclear power option. In 1998, CNESTEN started the construction of Nuclear Research Centre. The on going activities cover many sectors : earth and environmental sciences, high energy physics, safety and security, waste management. In 2001, CNESTEN started the construction of a 2MW TRiga Mark 2 Reactor, with the possibility to increase the power to 3 MW. The construction was achieved in January 2007. The operation of the reactor is expected for April 2007. The program of the utilization of the reactor was established with th contribution of the university and with the assistance of IAEA. Some of the experimental set-up installed around the reactor have been designed. CNESTEN has developed cooperation with Nuclear research centres from other countries and is receiving visitors and trainees mainly through the IAEA

  19. Results of MCNP analysis for Moroccan TRIGA Mark-II Reactor

    The construction work on the Moroccan Triga Mark II research reactor has already started and the first criticality is planned for the near future. The main objective of this study is to ensure that the calculations tools available at CNESTEN as the operator of this reactor are sufficiently adequate for the prediction of the neutronic and the operating characteristics of the first Moroccan research reactor. In this work, we have analyzed the 2 MW Triga Mark II reactor using the Monte Carlo code MCNP. In order to reduce possible errors due to inexact core geometry specification, a complete and exact 3D model of this reactor was developed. The parameters of interest in this study are the core excess reactivity, the critical size of the cold and clean core, the total reactivity worth of the control rods and the verification of the shutdown margin. (author)

  20. Decommissioning plan for TRIGA Mark-3

    Park, Seung Kook; Jung, Ki Jung

    1999-04-01

    TRIGA Mark-3(KRR-2) is the second research reactor in Korea. Construction of KRR-2 was started in 1969 and first criticality was achieved in 1972. After 24 years operation, KRR-2 has stopped its operation at the end of 1995 due to normal operation of HANARO. KRR-2 was then decided to decommission in 1996 by government. Decontamination and decommissioning(D and D) will be conducted in accordance with domestic laws and international regulations. Selected method of D and D will be devoted to protect workers and environment and to minimize radioactive wastes produced. The major D and D work will be conducted safely by using conventional industrial equipment because of relatively low radioactivity and contamination in the facility. When removing activated concrete from reactor pool, it will be installed a temporary containment and ventilation system. In this paper, structure of KRR-2 and method of D and D in each step are presented and discussed. (author). 12 refs., 8 tabs., 12 figs.

  1. Reconditioning of the TRIGA Mark III reactor

    The paper describes the activities carried out to recondition the TRIGA Mark III reactor at the Mexican Nuclear Centre, namely repair of its containment system, maintenance of its operational systems, and the obtaining of a licence for the facility and its operating staff. The process of initially obtaining the operating licence from the regulatory authority was affected by the existence of water leaks in the pool which were detected in March 1985 and were caused by corrosion in the reactor containment system. Reconditioning began with a series of activities aimed at locating, delimiting and repairing the areas damaged by corrosion and involved establishing criteria for selecting the most appropriate inspection, testing and repair methods. In order to obtain the operating licence, it was necessary to comply with various requirements laid down by the regulatory body. The most important requirements included: (a) repair of the reactor pool; (b) maintenance of its operational systems; (c) preparation and implementation of the Quality Control Programme; (d) updating of the Safety Report; (e) updating and preparation of operating, repair, radiation safety, emergency and administrative procedures; and (f) training of operating staff. In addition, the paper describes the work carried out at this reactor to widen its field of research and range of utilization. This work includes the reconditioning of a neutron diffractometer, the design and construction of a neutron diffractometer to determine the textures of materials, and the analysis of a new mixed core configuration based on fuels with 20% and 70% 235U enrichment. (author). 7 refs

  2. Analysis of safety limits of the Moroccan TRIGA MARK II research reactor

    Erradi, L.; Essadki, H.

    2001-06-01

    The main objective of this study is to check the ability of the Moroccan TRIGA MARK II research reactor, designed to use natural convection cooling, to operate at its nominal power (2 MW) with sufficient safety margins. The neutronic analysis of the core has been performed using Leopard and Mcrac codes and the parameters of interest were the power distributions, the power peaking factors and the core excess reactivity. The thermal hydraulic analysis of the TRIGA core was performed using the French code FLICA designed for transient and study state situations. The main safety related parameters of the core have been evaluated with special emphasises on the following: maximum fuel temperature, minimum DNBR and maximum void fraction. The obtained results confirm the designer predictions except for the void fraction.

  3. Analysis of safety limits of the Moroccan TRIGA MARK II research reactor

    The main objective of this study is to check the ability of the Moroccan TRIGA MARK II research reactor, designed to use natural convection cooling, to operate at its nominal power (2 MW) with sufficient safety margins. The neutronic analysis of the core has been performed using Leopard and Mcrac codes and the parameters of interest were the power distributions, the power peaking factors and the core excess reactivity. The thermal hydraulic analysis of the TRIGA core was performed using the French code FLICA designed for transient and study state situations. The main safety related parameters of the core have been evaluated with special emphasises on the following: maximum fuel temperature, minimum DNBR and maximum void fraction. The obtained results confirm the designer predictions except for the void fraction.

  4. Evaluation of TRIGA Mark II reactor in Turkey

    There are two research reactors in Turkey and one of them is the university Triga Mark II reactor which was in service since 1979 both for education and industrial application purposes. The main aim of this paper is to evaluate the spectrum of the services carried by Turkish Triga Mark II reactor. In this work, statistical distribution of the graduate works and applications, by using Triga Mark II reactor is examined and evaluated. In addition to this, technical and scientific uses of this above mentioned reactor are also investigated. It was already showed that the uses and benefits of this reactor can not be limited. If the sufficient work and service is given, NDT and industrial applications can also be carried economically. (orig.)

  5. TRIGA Mark II Ljubljana - spent fuel transportation

    The most important activity in 1999 was shipment of the spent fuel elements back to the United States for final disposal. This activity started already in 1998 with some governmental support. In July 1999 all spent fuel elements (219 pieces) from the TRIGA research reactor in Ljubljana were shipped back to the United Stated by the ship from the port Koper in Slovenia. At the same time shipment of the spent fuel from the research reactor in Pitesti, Romania, and the research reactor in Rome, Italy, was conducted. During the loading the radiation exposure to the workers was rather low. The loading and shipment of the spent nuclear fuel went very smoothly and according the accepted time table. During the last two years the TRIGA research reactor in Ljubljana has been in operation about 1100 hours per year and without any undesired shut-down. (authors)

  6. Preliminary feasibility study on TRIGA Mark-III upgrading

    The operation of a research and material testing reactor is required to meet rapidly increasing demands for radioisotopes to cope with domestic industrial growth and to respond to the material testing requirements for the localization of the nuclear power plant components. Therefore, the preliminary feasibility study on TRIGA Mark-III upgrading has been performed in regard to its technological and economic aspects. In this study, assumption is made in such a way that a 14 MW core is installed in the present TRIGA Mark-III pool. The nuclear analysis for this core shows that the average thermal neutron flux in the central experiment region is 1.8 x 1014n/cm2-sec, which meets the requirements of the large research and test reactor. Conceptural modification for the cooling system and radiation shielding structure has been suggested, and it shows that the TRIGA Mark-III can be upgraded to 14MW with a little change in the present structure. Our preliminary economic analysis shows that the TRIGA Mark-III upgrading would cost about half compared with the case of purchasing and installing a new research reactor on a new site. (author)

  7. Fast neutron flux determination of the STIF triga mark 2

    A Standard Triga Irradiation Facility (STIF) has been installed at Triga Mark 2 Reactor in Bandung. This facility is mainly used for experiment in the field of radiobiology. Using nickel as threshold detector, the measurement of fast flux has been carried out. The reaction is 58Ni(n,p)58Co. This detector has been chosen on account of its advantages, which are : long half life of Co-58, the absence of radioactivities obscuring the Co-58, easy measurement of 0,810 MeV gamma. The result of the measurement is 6,87 x 109 n/cm2 sec at 1000Kw power. (author)

  8. Thermal spectra of the TRIGA Mark III reactor; El espectro termico del reactor TRIGA Mark III

    Macias B, L.R.; Palacios G, J. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1998-07-01

    The diffraction phenomenon is gave in observance of the well known Bragg law in crystalline materials and this can be performance by mean of X-rays, electrons and neutrons among others, which allows to do inside the field of each one of these techniques the obtaining of measurements focussed at each one of them. For the present work, it will be mentioned only the referring to X-ray and neutron techniques. The X-ray diffraction due to its properties just it does measurements which are known in general as superficial measurements of the sample material but for the properties of the neutrons, this diffraction it explores in volumetric form the sample material. Since the neutron diffraction process depends lots of its intensity, then it is important to know the neutron source spectra that in this case is supplied by the TRIGA Mark III reactor. Within of diffraction techniques a great number of them can be found, however some of the traditional will be mentioned such as the identification of crystalline samples, phases identification and the textures measurement. At present this last technique is founded on the dot of a minimum error and the technique of phases identification performs but not compete with that which is obtained by mean of X-rays due to this last one has a major resolution. (Author)

  9. Safety analysis and optimization of the core fuel reloading for the Moroccan TRIGA Mark-II reactor

    Highlights: • Additional fresh fuel elements must be added to the reactor core. • TRIGA reactor could safely operate around 2 MW power with 12% fuel elements. • Thermal–hydraulic parameters were calculated and the safety margins are respected. • The 12% fuel elements will have no influence on the safety of the reactor. - Abstract: The Moroccan TRIGA MARK II reactor core is loaded with 8.5% in weight of uranium standard fuel elements. Additional fresh fuel elements must periodically be added to the core in order to remedy the observed low power and to return to the initial reactivity excess at the End Of Cycle. 12%-uranium fuel elements are available to relatively improve the short fuel lifetime associated with standard TRIGA elements. These elements have the same dimensions as standards elements, but with different uranium weight. The objective in this study is to demonstrate that the Moroccan TRIGA reactor could safely operate, around 2 MW power, with new configurations containing these 12% fuel elements. For this purpose, different safety related thermal–hydraulic parameters have been calculated in order to ensure that the safety margins are largely respected. Therefore, the PARET model for this TRIGA reactor that was previously developed and combined with the MCNP transport code in order to calculate the 3-D temperature distribution in the core and all the most important parameters like the axial distribution of DNBR (Departure from Nucleate Boiling Ratio) across the hottest channel. The most important conclusion is that the 12% fuel elements utilization will have no influence on the safety of the reactor while working around 2 MW power especially for configurations based on insertions in C and D-rings

  10. TRIGA MARK-II source term

    ORIGEN 2.2 are employed to obtain data regarding γ source term and the radio-activity of irradiated TRIGA fuel. The fuel composition are specified in grams for use as input data. Three types of fuel are irradiated in the reactor, each differs from the other in terms of the amount of Uranium compared to the total weight. Each fuel are irradiated for 365 days with 50 days time step. We obtain results on the total radioactivity of the fuel, the composition of activated materials, composition of fission products and the photon spectrum of the burned fuel. We investigate the differences of results using BWR and PWR library for ORIGEN. Finally, we compare the composition of major nuclides after 1 year irradiation of both ORIGEN library with results from WIMS. We found only minor disagreements between the yields of PWR and BWR libraries. In comparison with WIMS, the errors are a little bit more pronounced. To overcome this errors, the irradiation power used in ORIGEN could be increased a little, so that the differences in the yield of ORIGEN and WIMS could be reduced. A more permanent solution is to use a different code altogether to simulate burnup such as DRAGON and ORIGEN-S. The result of this study are essential for the design of radiation shielding from the fuel

  11. TRIGA MARK-II source term

    Full-text: ORIGEN 2.2 are employed to obtain data regarding g source term and the radio-activity of irradiated TRIGA fuel. The fuel composition are specified in grams for use as input data. Three types of fuel are irradiated in the reactor, each differs from the other in terms of the amount of Uranium compared to the total weight. Each fuel are irradiated for 365 days with 50 days time step. We obtain results on the total radioactivity of the fuel, the composition of activated materials, composition of fission products and the photon spectrum of the burned fuel. We investigate the differences of results using BWR and PWR library for ORIGEN. Finally, we compare the composition of major nuclides after 1 year irradiation of both ORIGEN library with results from WIMS. We found only minor disagreements between the yields of PWR and BWR libraries. In comparison with WIMS, the errors are a little bit more pronounced. To overcome this errors, the irradiation power used in ORIGEN could be increased a little, so that the differences in the yield of ORIGEN and WIMS could be reduced. A more permanent solution is to use a different code altogether to simulate burnup such as DRAGON and ORIGEN-S. The result of this study are essential for the design of radiation shielding from the fuel. (author)

  12. TRIGA MARK-II source term

    Usang, M. D., E-mail: mark-dennis@nuclearmalaysia.gov.my; Hamzah, N. S., E-mail: mark-dennis@nuclearmalaysia.gov.my; Abi, M. J. B., E-mail: mark-dennis@nuclearmalaysia.gov.my; Rawi, M. Z. M. Rawi, E-mail: mark-dennis@nuclearmalaysia.gov.my; Abu, M. P., E-mail: mark-dennis@nuclearmalaysia.gov.my [Bahagian Teknologi Reaktor, Agensi Nuklear Malaysia, 43000 Kajang (Malaysia)

    2014-02-12

    ORIGEN 2.2 are employed to obtain data regarding γ source term and the radio-activity of irradiated TRIGA fuel. The fuel composition are specified in grams for use as input data. Three types of fuel are irradiated in the reactor, each differs from the other in terms of the amount of Uranium compared to the total weight. Each fuel are irradiated for 365 days with 50 days time step. We obtain results on the total radioactivity of the fuel, the composition of activated materials, composition of fission products and the photon spectrum of the burned fuel. We investigate the differences of results using BWR and PWR library for ORIGEN. Finally, we compare the composition of major nuclides after 1 year irradiation of both ORIGEN library with results from WIMS. We found only minor disagreements between the yields of PWR and BWR libraries. In comparison with WIMS, the errors are a little bit more pronounced. To overcome this errors, the irradiation power used in ORIGEN could be increased a little, so that the differences in the yield of ORIGEN and WIMS could be reduced. A more permanent solution is to use a different code altogether to simulate burnup such as DRAGON and ORIGEN-S. The result of this study are essential for the design of radiation shielding from the fuel.

  13. TRIGA MARK-II source term

    Usang, M. D.; Hamzah, N. S.; J. B., Abi M.; M. Z., M. Rawi; Abu, M. P.

    2014-02-01

    ORIGEN 2.2 are employed to obtain data regarding γ source term and the radio-activity of irradiated TRIGA fuel. The fuel composition are specified in grams for use as input data. Three types of fuel are irradiated in the reactor, each differs from the other in terms of the amount of Uranium compared to the total weight. Each fuel are irradiated for 365 days with 50 days time step. We obtain results on the total radioactivity of the fuel, the composition of activated materials, composition of fission products and the photon spectrum of the burned fuel. We investigate the differences of results using BWR and PWR library for ORIGEN. Finally, we compare the composition of major nuclides after 1 year irradiation of both ORIGEN library with results from WIMS. We found only minor disagreements between the yields of PWR and BWR libraries. In comparison with WIMS, the errors are a little bit more pronounced. To overcome this errors, the irradiation power used in ORIGEN could be increased a little, so that the differences in the yield of ORIGEN and WIMS could be reduced. A more permanent solution is to use a different code altogether to simulate burnup such as DRAGON and ORIGEN-S. The result of this study are essential for the design of radiation shielding from the fuel.

  14. Component and operation experience of reactor TRIGA MARK II

    Reactor TRIGA MARK II is Jozef Stefan Institute's research reactor. It has been operating since 1966. A probabilistic approach of reactor safety estimation was used first in 1989 when a Probabilistic Safety Analysis (PSA) of the reactor was performed. A lack of reactor component data was found as the major problem in probabilistic assessment. It was decided to continue the work with specific data base development. The project has been divided in two phases. In the first phase specific data from year 1985 to 1990 were collected. In the second phase the collected data were treated. The comparison of generic and specific data showed significant difference between the generic and specific data and leads to a conclusion that a generic data based PSA has a limited credibility indicating that there is a need to build a specific data base for research reactors. The TRIGA MARK II research reactor has three major purposes: operator training, research involving neutrons and isotope production. The paper represents specific data base formation for TRIGA MARK II research reactor in Podgorica. Specific data on reactor scrams, components operation and human errors were collected. The data of fifteen components were estimated by classical and Bayesian method. The results of both methods are very different. Because of good specific data the results of classical methods were preferred. The comparison of specific and generic data showed that there is a great need to build a specific data base for research reactors. It is expected to use the specific data for existing PSA of TRIGA MARK II reactor reevaluation and optimisation of its operation. (authors)

  15. Power stabilization in CREN-K TRIGA Mark II reactor

    In order to eliminate power oscillations in the TRIGA MARK II reactor at the 'Centre Regional d'Etudes Nucleaires de Kinshasa' (CREN-K), Zaire, specially made adapters were put around the control rods in the top grid plate. The paper briefly describes how investigations were made to find out the basic reason of the power oscillations and the way these adapters were conceived and installed. (author)

  16. EVALUATION OF COOLING INSTRUMENTATION SYSTEM OF TRIGA MARK II REACTOR OF BANDUNG

    Evaluation of cooling instrumentation system of Triga Mark II reactor has been done. The reactor has been upgraded from 1 MW to 2 MW. The increasing of power is performed by changing the reactor components and systems. The reactor cooling system has important role in reactor operation, the system transfers heat produced in the core. The operation of the cooling system needed to be back up with qualified instrumentation. Evaluation has been done by doing analysis and observing the equipment design, type and clarification, performance study of instrumentation and system related to cooling system. It is known that the performance and system of Triga mark II reactor included the cooling system. It is also obtained the characteristic data of primary and secondary cooling system, piping diagram and instrumentation, emergency core cooling system. The cooling system has 4 measurement, i.e. flow rate, input and output temperature to heat exchanger, and electricity conductivity of water. The measurement can be observed from the reactor console. From this evaluation it is concluded that cooling system instrumentation followed the required criteria

  17. Accident scenarios of the TRIGA Mark II reactor in Vienna

    The safety report of the TRIGA Mark II reactor in Vienna includes three accident scenarios and their deterministic dose consequences to the environment. The destruction of the cladding of the most activated fuel element, the destruction of all fuel elements and a plane crash were considered scenarios in that report. The calculations were made in 1978 with the software program named STRISK. In this paper, the program package PC Cosyma was applied on the TRIGA Mark II reactor in Vienna and the deterministic consequences of the scenarios to the environment were updated. The fission product inventories of all fuel elements were calculated with ORIGEN2. To get meteorological data of the atmospheric condition around the release area, a weather station was installed. The release parameters were taken from the safety report or were replaced by worst case parameters. This paper focuses on two accident scenarios: the destruction of the cladding of the fuel element with the highest activity content and the case of a large plane crash. The current accident scenarios show good agreement with the calculations from 1978, hence no technical modifications in the safety report of the TRIGA reactor Vienna were necessary. Even in the very worst case scenario - complete destruction of all fuel elements in a large plane crash - the expected doses in the Atominstitut's neighborhood remain moderate.

  18. Accident scenarios of the TRIGA Mark II reactor in Vienna

    Villa, Mario, E-mail: mvilla@ati.ac.a [Vienna University of Technology, Atominstitut, Stadionallee 2, 1020 Wien (Austria); Haydn, Markus [Vienna University of Technology, Atominstitut, Stadionallee 2, 1020 Wien (Austria); Steinhauser, Georg, E-mail: georg.steinhauser@ati.ac.a [Vienna University of Technology, Atominstitut, Stadionallee 2, 1020 Wien (Austria); Boeck, Helmuth [Vienna University of Technology, Atominstitut, Stadionallee 2, 1020 Wien (Austria)

    2010-12-15

    The safety report of the TRIGA Mark II reactor in Vienna includes three accident scenarios and their deterministic dose consequences to the environment. The destruction of the cladding of the most activated fuel element, the destruction of all fuel elements and a plane crash were considered scenarios in that report. The calculations were made in 1978 with the software program named STRISK. In this paper, the program package PC Cosyma was applied on the TRIGA Mark II reactor in Vienna and the deterministic consequences of the scenarios to the environment were updated. The fission product inventories of all fuel elements were calculated with ORIGEN2. To get meteorological data of the atmospheric condition around the release area, a weather station was installed. The release parameters were taken from the safety report or were replaced by worst case parameters. This paper focuses on two accident scenarios: the destruction of the cladding of the fuel element with the highest activity content and the case of a large plane crash. The current accident scenarios show good agreement with the calculations from 1978, hence no technical modifications in the safety report of the TRIGA reactor Vienna were necessary. Even in the very worst case scenario - complete destruction of all fuel elements in a large plane crash - the expected doses in the Atominstitut's neighborhood remain moderate.

  19. Ljubljana TRIGA Mark II, 40 years of successful operation

    The research reactor TRIGA Mark II at the 'Jozef Stefan' Institute is located in the vicinity of Ljubljana. It was designed by General Atomics. It was commissioned in 1966 and reconstructed and equipped for pulse mode operation in 1991. It is a 250 kW light water pool type reactor cooled by natural convection and designed for training, research with neutrons and isotope production. The reactor has accumulated 40 years of continuous operation without any failure of major equipment or any event violating safety limits. After reconstruction, the reactor was loaded with fresh, low enriched fuel elements. All spent fuel elements were shipped back to the USA in 1999. Ten fresh fuel elements were exported to France in July 2007. The questions related to nuclear safety are treated in detail in a TRIGA Mark II Safety Analysis Report. The enforcement is provided by national and international bodies. New regulations for research reactors are currently under preparation in Slovenia. The requirement for a research reactor periodic safety review will be included in new regulations. The graded approach to safety is taken into account. Application of the IAEA 'Code of Conduct on the Safety of Research Reactors' will be accomplished through the new regulations pertaining to all stages in the life of the reactor. TRIGA has been playing an important role in developing nuclear technology and safety culture in Slovenia. At present it is planned that the reactor will operate at least until 2016. (author)

  20. Preliminary neutronic design of TRIGA Mark II Reactor

    It is very important to analyse the behaviour of the research reactors, since, they play a key role in developing the power reactor technology and radiation applications such as isotope generation for medical treatments. In this study, the neutronic behaviour of the TRIGA MARK II reactor, owned and operated by Istanbul Technical University is analysed by using the SCALE code system. In the analysis, in order to overcome the disadvantages of special TRIGA codes, such as TRIGAP, the SCALE code system is chosen to perform the calculations. TRIGAP and similar codes have limited geometrical (one-dimensional geometry) and cross sectional options (two-group calculations), however, SCALE has the capability of wider range of geometrical modelling capability (three-dimensional modelling is possible) and multi-group calculations are possible

  1. Analysis of safety limits of the Moroccan TRIGA MARK II research reactor

    A 2 MW TRIGA MARK II research reactor has been designed by General Atomics (GA) for the National Centre for Energy and Nuclear Sciences and Techniques (CNESTEN) in Morocco. This TRIGA reactor has the particularity of being the only TRIGA reactor designed to operate at the power level of 2 MW with the use of natural convection cooling. The main objective of this study is to check the ability of the reactor to operate at its nominal power with sufficient safety margins. The analysis of the reactor core starts from the basic reactor cells calculations which were performed for all the reactor cells using the LEOPARD code. The zone averaged group constants provided by cell calculations are used to compute the multiplication factor keff of the cold and clean core using the diffusion theory code Mcrac which is a recent version of the earlier code EXTERMINATOR-2. The main objective of the core calculations is to predict the core excess reactivity in cold zero power conditions and the power peaking factors which are very important data for the thermal hydraulic analysis of the core. For the maximum power peaking factors, our results agree with the values given by the reactor designer. Concerning the core excess reactivity, our results from both XY and RZ core calculations models lead to higher values than the results given by GA (about +2000 pcm). However, we should mention that GA results correspond probably to the minimum core excess reactivity which is guaranteed. The thermal hydraulic analysis of the TRIGA core was performed using the French code FLICA developed in CEA/Saclay for transient and study state thermal hydraulic analysis of a large variety of reactor cores. The objective of this analysis is to evaluate the main safety related parameters of the core and to ensure that they are within the safety limits in any operating conditions. The parameters considered in our study are: maximum fuel temperature, minimum DNBR and maximum void fraction. The obtained results

  2. Temperature feedback of TRIGA MARK-II fuel

    Usang, M. D., E-mail: mark-dennis@nuclearmalaysia.gov.my; Minhat, M. S.; Rabir, M. H.; Rawi, M. Z. M. [Malaysia Nuclear Agency, Bangi, 43000 Kajang, Selangor (Malaysia)

    2016-01-22

    We study the amount of temperature feedback on reactivity for the three types of TRIGA fuel i.. ST8, ST12 and LEU fuel, are used in the TRIGA MARK II reactor in Malaysia Nuclear Agency. We employ WIMSD-5B for the calculation of kin f for a single TRIGA fuel surrounded by water. Typical calculations of TRIGA fuel reactivity are usually limited to ST8 fuel, but in this paper our investigation extends to ST12 and LEU fuel. We look at the kin f of our model at various fuel temperatures and calculate the amount reactivity removed. In one instance, the water temperature is kept at room temperature of 300K to simulate sudden reactivity increase from startup. In another instance, we simulate the sudden temperature increase during normal operation where the water temperature is approximately 320K while observing the kin f at various fuel temperatures. For accidents, two cases are simulated. The first case is for water temperature at 370K and the other is without any water. We observe that the higher Uranium content fuel such as the ST12 and LEU have much smaller contribution to the reactivity in comparison to the often studied ST8 fuel. In fact the negative reactivity coefficient for LEU fuel at high temperature in water is only slightly larger to the negative reactivity coefficient for ST8 fuel in void. The performance of ST8 fuel in terms of negative reactivity coefficient is cut almost by half when it is in void. These results are essential in the safety evaluation of the reactor and should be carefully considered when choices of fuel for core reconfiguration are made.

  3. Temperature feedback of TRIGA MARK-II fuel

    Usang, M. D.; Minhat, M. S.; Rabir, M. H.; M. Rawi M., Z.

    2016-01-01

    We study the amount of temperature feedback on reactivity for the three types of TRIGA fuel i.. ST8, ST12 and LEU fuel, are used in the TRIGA MARK II reactor in Malaysia Nuclear Agency. We employ WIMSD-5B for the calculation of kin f for a single TRIGA fuel surrounded by water. Typical calculations of TRIGA fuel reactivity are usually limited to ST8 fuel, but in this paper our investigation extends to ST12 and LEU fuel. We look at the kin f of our model at various fuel temperatures and calculate the amount reactivity removed. In one instance, the water temperature is kept at room temperature of 300K to simulate sudden reactivity increase from startup. In another instance, we simulate the sudden temperature increase during normal operation where the water temperature is approximately 320K while observing the kin f at various fuel temperatures. For accidents, two cases are simulated. The first case is for water temperature at 370K and the other is without any water. We observe that the higher Uranium content fuel such as the ST12 and LEU have much smaller contribution to the reactivity in comparison to the often studied ST8 fuel. In fact the negative reactivity coefficient for LEU fuel at high temperature in water is only slightly larger to the negative reactivity coefficient for ST8 fuel in void. The performance of ST8 fuel in terms of negative reactivity coefficient is cut almost by half when it is in void. These results are essential in the safety evaluation of the reactor and should be carefully considered when choices of fuel for core reconfiguration are made.

  4. Temperature feedback of TRIGA MARK-II fuel

    We study the amount of temperature feedback on reactivity for the three types of TRIGA fuel i.. ST8, ST12 and LEU fuel, are used in the TRIGA MARK II reactor in Malaysia Nuclear Agency. We employ WIMSD-5B for the calculation of kin f for a single TRIGA fuel surrounded by water. Typical calculations of TRIGA fuel reactivity are usually limited to ST8 fuel, but in this paper our investigation extends to ST12 and LEU fuel. We look at the kin f of our model at various fuel temperatures and calculate the amount reactivity removed. In one instance, the water temperature is kept at room temperature of 300K to simulate sudden reactivity increase from startup. In another instance, we simulate the sudden temperature increase during normal operation where the water temperature is approximately 320K while observing the kin f at various fuel temperatures. For accidents, two cases are simulated. The first case is for water temperature at 370K and the other is without any water. We observe that the higher Uranium content fuel such as the ST12 and LEU have much smaller contribution to the reactivity in comparison to the often studied ST8 fuel. In fact the negative reactivity coefficient for LEU fuel at high temperature in water is only slightly larger to the negative reactivity coefficient for ST8 fuel in void. The performance of ST8 fuel in terms of negative reactivity coefficient is cut almost by half when it is in void. These results are essential in the safety evaluation of the reactor and should be carefully considered when choices of fuel for core reconfiguration are made

  5. The current status of Bandung Triga Mark II reactor, Indonesia

    Full text: The Bandung TRIGA Mark II Reactor - Indonesia was started-up on October 10, 1964 and it has been operated at power level of 250 kw. The facility has been, operated for research, production of radioisotopes and training. In 1971, the reactor has been upgraded from 250 kw to 1000 kw. Since that time the facility has been safely operating at various power levels of a maximum 1000 kw until February 1996, even though the reactor tank is kept unchanged. For a highly reliable reactor that can back-up the Ga Siwabessy Multipurpose Reactor - Jakarta, Indonesia, in producing sufficient radioisotopes, a higher power reactor is needed. This can be accomplished by increasing the thermal power of current TRIGA Mark II Bandung Reactor to 2000 kw as well as by enhancing the inherent and engineered safety features of the current reactor. The upgrading of reactor power shall ensure the increasing of neutron flux in the beam ports; hence the experiments such as neutron radiography, time of flight spectrometry and other nuclear physic experiments can be conducted better. For that the reactor tank, the number and configuration of fuel element, instrumentation and control rod, primary cooling system, secondary cooling system, water treatment system, shielding, etc. have been changed, and an Emergency Core Cooling System (ECCS) was added. One additional control rod, core configuration modification and enhancement of reactor shielding, shall increase the safety margin so that the reactor could be operated at a maximum power of 2000 kw. At the middle of May 2000 cold test (non-nuclear commissioning) was done, and continued to hot test (nuclear commissioning). Since June 24, 2000 the TRIGA Mark II Bandung has been operated at 2000 kw

  6. Neutron Imaging Using Neutrons From TRIGA MARK II PUSPATI Reactor

    This article reports about the implementation of neutron imaging work utilizing neutron beam from TRIGA MARK II PUSPATI collimation channels. Two methods have been implemented namely radiography and tomography. Advantage of these methods is the fact that, radiograms are obtained from normal radiographic imaging methodology and they are the projections used for tomographic image reconstruction. Therefore, both radiogram and tomogram are obtained consecutively. The method has been implemented on the round robin test sample for contrast and resolution measurement and also to some archaeological objects. (author)

  7. Operational experience data base of TRIGA Mark II reactor

    Two kinds of operational data available from operator logs: component failure-event data and abnormal event scenario information can be effectively used in PSA. Most operating data collection systems are aimed at improving the safety and availability of research reactors or commercial plants. This paper describes our failure-event data collection scheme, suitable for reliability and safety evaluations. Following the proposed data collection scheme the last five years operational experience was analysed and computerized data base for Triga Mark II reactor was developed. (orig.)

  8. Thermal - hydraulic analysis of the ITU TRIGA Mark - II reactor

    Experimental and analytical studies have been performed to find out the temperature distribution, as a function of reactor power, in the TRIGA Mark-II reactor at Istanbul Technical University. A two-dimensional computer code was written in FORTRAN-77 language numerically solves heat conduction equation using finite difference method at the steady state. The calculated results for fuel temperature and coolant temperature distribution in the reactor core for different reactor power were compared with the experimental data. Agreements between experiment and results from the computer program are fairly good

  9. Accident scenarios of the TRIGA Mark II reactor in Vienna

    The safety report of the TRIGA Mark II reactor in Vienna includes three accident scenarios and their deterministic dose consequence to the environment. The destruction of the most activated fuel element, the destruction of all fuel elements and a plane crash were treated scenarios in that report. The calculations were made in 1978 with the computer program STRISK. In this work, the program package PC COSYMA was applied on the TRIGA Mark II reactor in Vienna and the deterministic consequences of the scenarios to the environment were updated. The fission product inventories of all fuel elements were taken from a calculation with ORIGEN2. To get meteorological data of the atmospheric condition around the release area, a weather station was installed. The release parameters were taken from the safety report or were replaced by worst case parameters. Further on, a fourth scenario for the case of a small plane crash was added. For the sake of completeness all scenarios were calculated with different atmospheric conditions. In this paper only two accident scenarios are presented, the destruction of the fuel element with the highest activity content and the case of a large plane crash, which means a totally destruction of the reactor hall. (author)

  10. The optimal control of ITU TRIGA Mark II Reactor

    In this study, optimal control of ITU TRIGA Mark-II Reactor is discussed. A new controller has been designed for ITU TRIGA Mark-II Reactor. The controller consists of main and auxiliary controllers. The form is based on Pontragyn's Maximum Principle and the latter is based on PID approach. For the desired power program, a cubic function is chosen. Integral Performance Index includes the mean square of error function and the effect of selected period on the power variation. YAVCAN2 Neutronic - Thermal -Hydraulic code is used to solve the equations, namely 11 equations, dealing with neutronic - thermal - hydraulic behavior of the reactor. For the controller design, a new code, KONTCAN, is written. In the application of the code, it is seen that the controller controls the reactor power to follow the desired power program. The overshoot value alters between 100 W and 500 W depending on the selected period. There is no undershoot. The controller rapidly increases reactivity, then decreases, after that increases it until the effect of temperature feedback is compensated. Error function varies between 0-1 kW. (author)

  11. Ljubljana TRIGA Mark II, 40 years of successful operation

    The research reactor TRIGA Mark II is part of the Jozef Stefan Institute, located near Ljubljana. It was built by General Atomics. The research reactor was commissioned in 1966 and in 1991 it was reconstructed and equipped for pulse mode operation. The reactor TRIGA Mark II is a typical 250 kW light water reactor cooled by natural convection. It is designed for training in reactor operation and technology, research with neutrons and isotope production. It has been used for experiments in the following fields: solid state physics, neutron radiography, reactor physics including burn up measurements and calculations, boron neutron capture therapy, environmental studies and researches of advanced materials. The reactor has accumulated 40 years of continuous operation without any failure of major equipment or any event violating safety standards. There has been no release of radioactivity into the environment exceeding limiting values prescribed by the regulatory requirements. Major refurbishment included installation of a pulse rod, reconstruction of control mechanisms and control units, replacement of the primary coolant pumps with new ones, modification of a spent fuel storage pool and installation of new pneumatic mail. The United States nuclear non-proliferation policy provided Slovenia with the opportunity to return the spent fuel from the research reactor TRIGA Mark II back to the USA. After reconstruction, the reactor was loaded with fresh low enrichment fuel elements and all spent fuel elements were shipped back to the USA in July 1999. At present there are 94 fuel elements with 20% enriched uranium on site. All questions related to nuclear safety are treated in detail in a Safety Analysis Report. Its operation is regulated by several national and international nuclear laws, regulations and standards. The enforcement is provided by national and international bodies: Slovenian Nuclear Safety Administration (SNSA), Health Inspectorate of the Republic of Slovenia

  12. Monte Carlo simulation of the TRIGA mark 2 criticality experiment

    The criticality analysis of the TRIGA-2 bench-mark experiment at the Musashi Institute of Technology Research Reactor (MuITR, 100 kW) was performed by the three-dimensional continuous-energy Monte Carlo code (MCNP4A). To minimize errors due to an inexact geometry model, all fresh fuel and control rods as well as vicinity of the core were precisely modeled. Core multiplication factors (Keff) in the initial core critical experiment and in the excess reactivity adjustment for the several fuel-loading patterns as well as the fuel element reactivity worth distributions were used in the validation process of the physical model and neutron cross section data from the ENDF/B-V evaluation. The calculated Keff overestimated the experimental data by 1.0% for both the initial core and the several fuel-loading arrangements (fuel or graphite element was added only to the outer-ring), but the discrepancy increased to 1.8% for the some fuel-loading patterns (graphite element was positioned in the inner-ring). The comparison result of the fuel element worth distribution showed above tendency. Al in all, the agreement between the MCNP predictions and the experimentally determined values is good, which indicates that the Monte Carlo model is enough to simulate criticality of the TRIGA-2 reactor. (author)

  13. Decommissioning of the ICI TRIGA Mark I reactor

    Parry, D.R.; England, M.R.; Ward, A. [BNFL, Sellafield (United Kingdom); Green, D. [ICI Chemical Polymers Ltd, Billingham (United Kingdom)

    2000-07-01

    This paper considers the fuel removal, transportation and subsequent decommissioning of the ICI TRIGA Mark I Reactor at Billingham, UK. BNFL Waste Management and Decommissioning carried out this work on behalf of ICI. The decommissioning methodology was considered in the four stages to be described, namely Preparatory Works, Reactor Defueling, Intermediate Level Waste Removal and Low Level Waste Removal. This paper describes the principal methodologies involved in the defueling of the reactor and subsequent decommissioning operations, highlighting in particular the design and safety case methodologies used in order to achieve a solution which was completed without incident or accident and resulted in a cumulative radiation dose to personnel of only 1.57 mSv. (author)

  14. Testing Of Secondary Cooling Component Of TRIGA Mark Reactor

    The aim of this activity is to improve the knowledge of the mechanical testing technology of the research reactor cooling pipe material. The way which was chosen is through a series of testing to know the mechanical properties of carbon steel pipe used in TRIGA-MARK II secondary cooling pipe. Scopes of these testing activities are tensile testing, hardness testing, chemical composition analysis, and metallography analysis. Visual examination shows that thickness of the pipe was reduced over the range 0.31-1.76 mm and there was scales inside the pipe about 7.1-9.1 mm. Result of the mechanical testing shows that ultimate tensile strength, yield strength, elongation and. hardness of that material are 39 kg mm2, 34 kg/mm2, 38 %, and HV161, respectively. That yield strength value is on the design range

  15. Decommissioning of the ICI TRIGA Mark I reactor

    This paper considers the fuel removal, transportation and subsequent decommissioning of the ICI TRIGA Mark I Reactor at Billingham, UK. BNFL Waste Management and Decommissioning carried out this work on behalf of ICI. The decommissioning methodology was considered in the four stages to be described, namely Preparatory Works, Reactor Defueling, Intermediate Level Waste Removal and Low Level Waste Removal. This paper describes the principal methodologies involved in the defueling of the reactor and subsequent decommissioning operations, highlighting in particular the design and safety case methodologies used in order to achieve a solution which was completed without incident or accident and resulted in a cumulative radiation dose to personnel of only 1.57 mSv. (author)

  16. MCNP simulation of the TRIGA Mark II benchmark experiment

    The complete 3D MCNP model of the TRIGA Mark II reactor is presented. It enables precise calculations of some quantities of interest in a steady-state mode of operation. Calculational results are compared to the experimental results gathered during reactor reconstruction in 1992. Since the operating conditions were well defined at that time, the experimental results can be used as a benchmark. It may be noted that this benchmark is one of very few high enrichment benchmarks available. In our simulations experimental conditions were thoroughly simulated: fuel elements and control rods were precisely modeled as well as entire core configuration and the vicinity of the core. ENDF/B-VI and ENDF/B-V libraries were used. Partial results of benchmark calculations are presented. Excellent agreement of core criticality, excess reactivity and control rod worths can be observed. (author)

  17. Ageing Management in the CENM Triga Mark II Research Reactor

    Physical ageing is one of the most important factors that may reduce the safety margins calculated in the design of safety system components of a research reactor. In this context, special efforts are necessary for ensuring the safety of research reactors through appropriate ageing management actions. The paper deals with the overall aspects of the ageing management system of the Moroccan TRIGA Mark II research reactor. The management system covers among others, management of structures, critical components inspections, the control command system and nuclear instrumentation verification. The paper presents also how maintenance and periodic testing are organized and managed in the reactor module. Practical examples of ageing management actions of some systems and components during recent years are presented. (author)

  18. The reactor noise analysis for a TRIGA Mark-II

    For the purpose of measurement of reactor kinetic parameter, rossi-α experiment in TRIGA Mark-II reactor are performed. The past neutron noise measurement which is using HARDWARE have had defects of inaccuracy. In this study, I developed SOFTWARE to betterment of these defects and using it investigated α which is reciprocal of prompt period. To collect neutron pulses, developed data acquisition system using 16 bit personal computer (IBM-AT) and developed pascal language program to analysis neutron pulses. As a result of experiment, α is 103, 5, 155.6, 172.7, 238.7, 266.5 (1/sec) at -1, -20, -40, -60, -80, (cent) respectively, and compare it with other experiment data convinced accurate, know S/B ratio must be larger then 10% and in case of thermal reactor, low power reactor such as AGN-201 is needed to neutron noise analysis. (Author)

  19. Control System Dynamics Analysis Of TRIGA Mark II Bandung

    The root locus analysis of TRIGA MARK II reactor was performed. The parameters were calculated based from the experimental data. The experiment was performed between 100 kW to 1 MW of power, average fuel temperature was 189oC and water average temperature was 37.3oC to measure temperature and xenon poisoning feedback. On the design analysis of PID system the characteristic of the controller are gain K=2.72, tp=13.65 seconds, Mp=0.0075%, Ti=4.1 seconds and Td=0.24 seconds. The controller transient time is less than 30 seconds and the settling time is less than 2% as well

  20. Operating experience at the Reed College TRIGA Mark I facility

    Full text: Reed College is unique among small liberal arts colleges in that it operates a TRIGA Mark I reactor (250 kw - steady stage). There is no full time staff and all operators are undergraduate students in physics and chemistry. Training of new operators is done through a weekly seminar run throughout the school year with intensive work during January or summer vacation periods. 16 of 21 students who have taken the licensing exams have received their license. The Reactor has logged about 165 MW hrs of operation, which is equivalent to an average of 4 hours at full power per week. Most of this time has been used for sample activation, primarily neutron activation analysis with reactor training and testing operations next. Significant amounts of time have also been spent for demonstration operations for high school groups and the general public (800-1000 visitors annually) and neutron radiography. A consortium of seven local colleges has been organized to increase facility utilization. This consortium is now being funded by two local electric power companies who are planning to build nuclear power plants. Some major problems that have arisen in 3 1/2 years of operation are: 1. Slave system 2. Rotary specimen rack locking pin 3. Rapid wear of primary water system pressure gauges 4. Count rate channel preamp and bistable circuit 5. Fishing pole 6. Reg rod drive motor failure 7. % power channel UIC short and sticking scam relay. These problems have not caused a significant amount of down time and generally we have been able to run experiments on schedule. However, with the limited staff we have available, any problem is time-consuming. Finally, I would like to suggest that Gulf Energy and Environmental Systems stock the more expensive items of a TRIGA reactor (e.g., control rod drive motors, ion chambers, etc.) so that they can be readily replaced in the event of failure. (author)

  1. Computational analysis of neutronic parameters of CENM TRIGA Mark II research reactor

    The CENM TRIGA MARK II reactor is part of the National Center for Energy, Sciences and Nuclear Techniques (CNESTEN). It's a standard design 2MW, natural-convection-cooled reactor with a graphite reflector containing 4 beam tubes and a thermal column. The reactor has several applications in different fields as industry, agriculture, medicine, training and education. In the present work a computational study has been carried out in the framework of neutronic parameters studies of the reactor. A detailed MCNP model that include all elements of the core and surrounding structures has been developed to calculate different parameters of the core (The effective multiplication factor, reactivity experiments comprising control rods worth, excess reactivity and shutdown margin). Further calculations have been carried out to calculate the neutron flux profiles at different locations of the reactor core. The cross sections used are processed from the library provided with MCNP5 and based on the ENDF/B-VII with continuous dependence in energy and special treatment of thermal neutrons in lightweight materials. (author)

  2. Fuel element situation and performance data TRIGA Mark II reactor

    Electronic data acquisition of the position and movement of Triga fuel elements (FE) in the TRIGA II Vienna reactor was the objective of this project. Using one month power data and the Fuel element position in core it is possible to calculate their burnup. Fuel element performance data during 1962 to 2003 are provided. (nevyjel)

  3. 44 years of operation - The successful fuel history of the TRIGA Mark II reactor Vienna

    A review is given on the fuel element situation of the TRIGA Mark II reactor Vienna after 44 years of operation. Since March 7th, 1962, the TRIGA Mark II reactor Vienna operates with an average of 263 MWh per year, which corresponds to a uranium burn-up of 11.5 g per year. Presently we have 82 TRIGA fuel elements in the core, 51 of them are old aluminium clad elements from the initial criticality while the rest are stainless steel clad elements which had been added later to compensate the uranium consumption. (author)

  4. Proposal of LDR Ir-192 Production in the TRIGA Mark II Research Reactor

    Karimzadeh, S.; Khan, R.; Boeck, H., E-mail: Sam.karimzadeh@ati.ac.a, E-mail: Nrustam@ati.ac.a, E-mail: Boeck@ati.ac.a [Institute of Atomic and Subatomic Physics (ATI), Vienna University of Technology (TU-Vienna) Stadionallee 2, 1020-Vienna (Austria)

    2011-07-01

    The TRIGA MARK II research reactor in Vienna provides some irradiation positions with different flux distribution. In this regard, a case study is under investigation to appraise the possibility of medical radioisotope production in Vienna. For this purpose, neutron flux mapping and the axial neutron flux distribution are calculated by MCNP5 for the TRIGA Mark II core. This paper describes the feasibility of Low Dose Rate (LDR) {sup 192}Ir production in the core of the low power research reactor. (author)

  5. Proposal of LDR Ir-192 Production in the TRIGA Mark II Research Reactor

    The TRIGA MARK II research reactor in Vienna provides some irradiation positions with different flux distribution. In this regard, a case study is under investigation to appraise the possibility of medical radioisotope production in Vienna. For this purpose, neutron flux mapping and the axial neutron flux distribution are calculated by MCNP5 for the TRIGA Mark II core. This paper describes the feasibility of Low Dose Rate (LDR) 192Ir production in the core of the low power research reactor. (author)

  6. On Line Measurement of Reactivity Worth of TRIGA Mark-II Research Reactor Control Rods

    Nusrat Jahan; Mamunur M. Rashid; F. Ahmed; M. G. S. Islam; M. Aliuzzaman; Islam, S.M.A

    2011-01-01

    The reactivity worth measurement system for control rods of the TRIGA MARK-II research reactor of Bangladesh has been design and developed. The theory of the kinetic technique of measuring reactivity has been used by this measurement system. The system comprises of indigenous hardware and software for online acquisition of neutron flux signals from reactor console and then computes the reactivity worth accordingly. Here for the TRIGA MARK-II research reactor, the reactivity measurement system...

  7. About the safety analysis of Istanbul TRIGA Mark II reactor

    The accidents potentially related to the operation of TRIGA Mark-II reactor have been analysed in Safety Analysis Report of ITU Research Reactor, with special consideration being given to site characteristics. The maximum credible accident which can take place in a swimming pool type research reactor - accidental dropping of a fuel element into of the critical reactor core - is considered. In the safety analysis of pool type reactors BORAX accident is also included. The following events are abnormal incidents that should be taken into account: 1. Cladding rupture. 2. Reactivity accident. 3. Loss of coolant accident. Fission product release during an accident is analysed. Even though the possibility is believed to be exceedingly remote, the most unfavourable assumptions are made: the rapid insertion of the total excess' reactivity in the reactor operating at a power less then 1 kW; Coincidence of the reactivity insertion and loss of coolant accident; Cladding rupture occurring at one of the highest power density fuel elements as a consequence; Emergency ventilation system failure, leading to a vanishing filter efficiency. It is shown that, even under this most unfavourable condition, the maximum radiation to which the nearby inhabitants will be subjected, is 3.8 x 10-2 mRem per 1/2 hr. Even in the hypothetical case of the coincidence of four abnormal incidents the resulting radiation dose to the population does not exceed much the magnitude of the permissible dose of the ICRP recommendations

  8. Thermal spectra of the TRIGA Mark III reactor

    The diffraction phenomenon is gave in observance of the well known Bragg law in crystalline materials and this can be performance by mean of X-rays, electrons and neutrons among others, which allows to do inside the field of each one of these techniques the obtaining of measurements focussed at each one of them. For the present work, it will be mentioned only the referring to X-ray and neutron techniques. The X-ray diffraction due to its properties just it does measurements which are known in general as superficial measurements of the sample material but for the properties of the neutrons, this diffraction it explores in volumetric form the sample material. Since the neutron diffraction process depends lots of its intensity, then it is important to know the neutron source spectra that in this case is supplied by the TRIGA Mark III reactor. Within of diffraction techniques a great number of them can be found, however some of the traditional will be mentioned such as the identification of crystalline samples, phases identification and the textures measurement. At present this last technique is founded on the dot of a minimum error and the technique of phases identification performs but not compete with that which is obtained by mean of X-rays due to this last one has a major resolution. (Author)

  9. Perturbation analysis of the TRIGA Mark II reactor Vienna

    The safety design of a nuclear reactor needs to maintain the steady state operation at desired power level. The safe and reliable reactor operation demands the complete knowledge of the core multiplication and its changes during the reactor operation. Therefore it is frequently of interest to compute the changes in core multiplication caused by small disturbances in the field of reactor physics. These disturbances can be created either by geometry or composition changes of the core. Fortunately if these changes (or perturbations) are very small, one does not have to repeat the reactivity calculations. This article focuses the study of small perturbations created in the Central Irradiation Channel (CIC) of the TRIGA mark II core to investigate their reactivity influences on the core reactivity. For this purpose, 3 different kinds of perturbations are created by inserting 3 different samples in the CIC. The cylindrical void (air), heavy water (D2O) and Cadmium (Cd) samples are inserted into the CIC separately to determine their neutronics behavior along the length of the core. The Monte Carlo N-Particle radiation transport code (MCNP) is applied to simulate these perturbations in the CIC. The MCNP theoretical predictions are verified by the experiments performed on the current reactor core. The behavior of void in the whole core and its dependence on position and water fraction is also presented in this article. (orig.)

  10. Perturbation analysis of the TRIGA Mark II reactor Vienna

    Khan, R. [Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad (Pakistan); Villa, M.; Stummer, T.; Boeck, H. [Vienna Univ. of Technology (Austria). Atominstitut; Saeedbadshah [International Islamic Univ., Islamabad (Pakistan)

    2013-04-15

    The safety design of a nuclear reactor needs to maintain the steady state operation at desired power level. The safe and reliable reactor operation demands the complete knowledge of the core multiplication and its changes during the reactor operation. Therefore it is frequently of interest to compute the changes in core multiplication caused by small disturbances in the field of reactor physics. These disturbances can be created either by geometry or composition changes of the core. Fortunately if these changes (or perturbations) are very small, one does not have to repeat the reactivity calculations. This article focuses the study of small perturbations created in the Central Irradiation Channel (CIC) of the TRIGA mark II core to investigate their reactivity influences on the core reactivity. For this purpose, 3 different kinds of perturbations are created by inserting 3 different samples in the CIC. The cylindrical void (air), heavy water (D2O) and Cadmium (Cd) samples are inserted into the CIC separately to determine their neutronics behavior along the length of the core. The Monte Carlo N-Particle radiation transport code (MCNP) is applied to simulate these perturbations in the CIC. The MCNP theoretical predictions are verified by the experiments performed on the current reactor core. The behavior of void in the whole core and its dependence on position and water fraction is also presented in this article. (orig.)

  11. TRIGA Mark II Criticality Benchmark Experiment with Burned Fuel

    The experimental results of criticality benchmark experiments performed at the Jozef Stefan Institute TRIGA Mark II reactor are presented. The experiments were performed with partly burned fuel in two compact and uniform core configurations in the same arrangements as were used in the fresh fuel criticality benchmark experiment performed in 1991. In the experiments, both core configurations contained only 12 wt% U-ZrH fuel with 20% enriched uranium. The first experimental core contained 43 fuel elements with average burnup of 1.22 MWd or 2.8% 235U burned. The last experimental core configuration was composed of 48 fuel elements with average burnup of 1.15 MWd or 2.6% 235U burned. The experimental determination of keff for both core configurations, one subcritical and one critical, are presented. Burnup for all fuel elements was calculated in two-dimensional four-group diffusion approximation using the TRIGLAV code. The burnup of several fuel elements was measured also by the reactivity method

  12. Different microprocessor controlled devices for ITU TRIGA Mark II reactor

    In this paper the design of a period meter and multichannel thermometer, which are controlled by a microprocessor, in order to be used at ITU TRIGA Mark-II Reactor is presented. The system works as a simple microcomputer, which includes a CPU, a EPROM, a RAM, a CTC, a PIO, a PIA a keyboard and displays, using the assembly language. The period meter can work either with pulse signal or with analog signal depending on demand of the user. The period is calculated by software and its range is -99,9 sec, to +2.1 sec. When the period drops +3 sec, the system gives alarm illuminating a LED. The multichannel thermometer has eight temperature channels. Temperature channels can manually or automatically be selected. The channel selection time can be adjusted. The thermometer gives alarm illuminating a LED, when the temperature rises to 600 C. Temperature data is stored in the RAM and is shown on a display. This system provides us to use four spare thermocouples in the reactor. (orig.)

  13. Neutronic Analysis of the 3 MW TRIGA MARK II Research Reactor, Part II: Benchmark Analysis of TRIGA Experiments

    The three-dimensional continuous-energy Monte Carlo code MCNP4C was used to develop a versatile and accurate full-core model of the TRIGA MARK II research reactor at AERE, Savar. Thr consistency and accuracy of both the Monte Carlo simulation and neutron transport physics was established by benchmarking the TRIGA experiments. Analysis of neutron flux and reactivity experiments comprising control rod worths, critical rod height, excess reactivity and shutdown margin were used in the validation process. Calculations of fast neutron flux, and fuel and graphite element worths distribution are also presented. Good agreement between the experiments and MCNP calculations indicate that the simulation of TRIGA reactor is treated adequately. (author)

  14. Transient behavior during reactivity insertion in the Moroccan TRIGA Mark II reactor using the PARET/ANL code

    Boulaich, Y., E-mail: boulaich@cnesten.org.ma [CEN-Maamora, CNESTEN, Rabat (Morocco); Nacir, B. [CEN-Maamora, CNESTEN, Rabat (Morocco); El Bardouni, T. [Radiations and Nuclear Systems Laboratory, University Abdelmalek Essaadi, Faculty of Sciences of Tetouan (Morocco); CEN-Maamora, CNESTEN, Rabat (Morocco); Boukhal, H. [Radiations and Nuclear Systems Laboratory, University Abdelmalek Essaadi, Faculty of Sciences of Tetouan (Morocco); Chakir, E. [LHESIR, Department of Physics, Faculty of Sciences, Kénitra (Morocco); El Bakkari, B.; El Younoussi, C. [CEN-Maamora, CNESTEN, Rabat (Morocco)

    2015-04-01

    Highlights: • PARET model for the Moroccan TRIGA MARK II reactor has been developed. • Transient behavior under reactivity insertion has been studied based on PARET code. • Power factors required by PARET code have been calculated by using MCNP5 code. • The dependence on time of the main thermal-hydraulic parameters was calculated. • Results are largely far to compromise the thermal design limits. - Abstract: A three dimensional model for the Moroccan 2 MW TRIGA MARK II reactor has been developed for thermal-hydraulic and safety analysis by using the PARET/ANL and MCNP5 codes. This reactor is located at the nuclear studies center of Mâamora (CENM), Morocco. The model has been validated through temperature measurements inside two instrumented fuel elements located near the center of the core, at various power levels, and also through the power and fuel temperature evolution after the reactor shutdown (SCRAM). The axial distributions of power factors required by the PARET code have been calculated in each fuel element rod by using MCNP5 code. Based on this thermal-hydraulic model, a safety analysis under the reactivity insertion phenomenon has been carried out and the dependence on time of the main thermal-hydraulic parameters was calculated. Results were compared to the thermal design limits imposed to maintain the integrity of the clad.

  15. Transient behavior during reactivity insertion in the Moroccan TRIGA Mark II reactor using the PARET/ANL code

    Highlights: • PARET model for the Moroccan TRIGA MARK II reactor has been developed. • Transient behavior under reactivity insertion has been studied based on PARET code. • Power factors required by PARET code have been calculated by using MCNP5 code. • The dependence on time of the main thermal-hydraulic parameters was calculated. • Results are largely far to compromise the thermal design limits. - Abstract: A three dimensional model for the Moroccan 2 MW TRIGA MARK II reactor has been developed for thermal-hydraulic and safety analysis by using the PARET/ANL and MCNP5 codes. This reactor is located at the nuclear studies center of Mâamora (CENM), Morocco. The model has been validated through temperature measurements inside two instrumented fuel elements located near the center of the core, at various power levels, and also through the power and fuel temperature evolution after the reactor shutdown (SCRAM). The axial distributions of power factors required by the PARET code have been calculated in each fuel element rod by using MCNP5 code. Based on this thermal-hydraulic model, a safety analysis under the reactivity insertion phenomenon has been carried out and the dependence on time of the main thermal-hydraulic parameters was calculated. Results were compared to the thermal design limits imposed to maintain the integrity of the clad

  16. Analysis of JSI TRIGA MARK II reactor physical parameters calculated with TRIPOLI and MCNP

    New computational model of the JSI TRIGA Mark II research reactor was built for TRIPOLI computer code and compared with existing MCNP code model. The same modelling assumptions were used in order to check the differences of the mathematical models of both Monte Carlo codes. Differences between the TRIPOLI and MCNP predictions of keff were up to 100 pcm. Further validation was performed with analyses of the normalized reaction rates and computations of kinetic parameters for various core configurations. - Highlights: • TRIGA Benchmark keff calculated with the TRIPOLI code. • Reaction rate profiles in TRIGA calculated with TRIPOLI code. • TRIPOLI model of the JSI TRIGA was validated. • TRIGA Kinetic parameters were calculated with TRIPOLI code. • All results are in good agreement, largest discrepancies due to nuclear data

  17. Analysis of cocked fuel elements in the AFRRI TRIGA Mark-F reactor

    The Armed Forces Radiobiology Research Institute (AFRRI) TRIGA Mark-F pulsing reactor has experienced eight cocked fuel elements during the period 5 November 1974 through 17 February 1982. Although there are no adverse health and safety consequences associated with their occurrence and there is no credible potential for system damage, cocked TRIGA fuel elements do cause inconvenience to the reactor staff and a temporary delay in operations. This paper presents the history of cocked TRIGA fuel elements at AFRRI, discusses possible mechanisms for their occurrence, and outlines a plan to isolate and ultimately determine their actual cause

  18. Numerical simulation of non-steady state neutron kinetics of the TRIGA Mark II reactor Vienna

    Riede, Julia; Boeck, Helmuth

    2013-01-01

    This paper presents an algorithm for numerical simulations of non-steady states of the TRIGA MARK II reactor in Vienna, Austria. The primary focus of this work has been the development of an algorithm which provides time series of integral neutron flux after reactivity changes introduced by perturbations without the usage of thermal-hydraulic / neutronic numerical code systems for the TRIGA reactor in Vienna, Austria. The algorithm presented takes into account both external reactivity changes...

  19. Twenty years of operation of Ljubljana's TRIGA Mark II reactor

    Twenty years have now passed since the start of the TRIGA Mark II reactor in Ljubljana. The reactor was critical on May 31, 1966. The total energy produced until the end of May 1986 was 14.048 MWh or 585 MWd. For the first 14 years (until 1981) the yearly energy produced was about 600 MWh, since 1981 the yearly energy produced was 1000 MWh when a routine radioactive isotopes production started for medical use as well as other industrial applications, such as doping and irradiation with fast neutrons of silicon monocrystals, production of level indicators (irradiated cobalt wire), production of radioactive iridium for gamma-radiography, leak detection in pipes by sodium, etc. Besides these, applied research around the reactor is being conducted in the following main fields, where- many unique methods have been developed or have found their way into the local industry or hospitals: neutron radiography, neutron induced auto-radiography using solid state nuclear track detectors, nondestructive methods for assessment of nuclear burn-up, neutron dosimetry, calculation of core burn-up for the optimal in-core fuel management strategy. The solvent extraction method was developed for the everyday production of 99mTc, which is the most widely used radionuclide in diagnostic nuclear medicine. The methods were developed for the production of the following isotopes: 18F, 85mKr, 24Na, 82Br, 64Zn, 125I. Neutron activation analysis represents one of the major usages for the TRIGA reactor. Basic research is being conducted in the following main fields: solid state physics (elastic and inelastic scattering of the neutrons), neutron dosimetry, neutron radiography, reactor physics and neutron activation analysis. The reactor is used very extensively as a main instrument in the Reactor Training Centre in Ljubljana where manpower training for our nuclear power plant and other organisations has been performed. Although the reactor was designed very carefully in order to be used for

  20. Steady-state thermal-hydraulic analysis of the Moroccan TRIGA MARK II reactor by using PARET/ANL and COOLOD-N2 codes

    Research highlights: → The COOLOD/N2 and PARET/ANL codes were used for a steady-state thermal-hydraulic and safety analysis of the 2 MW TRIGA MARK II reactor located at the Nuclear Studies Center of Maamora (CENM), Morocco. → The main objective of this study is to ensure the safety margins of different safety related parameters by steady-state calculations at full power level (2 MW). → The most important conclusion is that all obtained values of DNBR, fuel center and surface temperature, cladding surface temperature and coolant temperature across the hottest channel are largely far to compromise safety of the reactor. - Abstract: The COOLOD/N2 and PARET/ANL codes were used for a steady-state thermal-hydraulic and safety analysis of the 2 MW TRIGA MARK II reactor located at the Nuclear Studies Center of Maamora (CENM), Morocco. In order to validate our PARET/ANL and COOLOD-N2 models, the fuel center temperature as function of core power was calculated and compared with the corresponding experimental values. The comparison indicates that the calculated values are in satisfactory agreement with the measurement. The main objective of this study is to ensure the safety margins of different safety related parameters by steady-state calculations at full power level (2 MW). Therefore, we have calculated the departure from nucleate boiling ratio (DNBR), fuel center and surface temperature, cladding surface temperature and coolant temperature profiles across the hottest channel. The most important conclusion is that all obtained values are largely far to compromise safety of the reactor.

  1. Steady-state thermal-hydraulic analysis of the Moroccan TRIGA MARK II reactor by using PARET/ANL and COOLOD-N2 codes

    Boulaich, Y., E-mail: boulaich@cnesten.org.m [CEN-Maamora, CNESTEN, Rabat (Morocco); Radiations and Nuclear Systems Laboratory, University Abdelmalek Essaadi, Faculty of Sciences of Tetuan (Morocco); Nacir, B. [CEN-Maamora, CNESTEN, Rabat (Morocco); El Bardouni, T.; Zoubair, M. [Radiations and Nuclear Systems Laboratory, University Abdelmalek Essaadi, Faculty of Sciences of Tetuan (Morocco); El Bakkari, B. [CEN-Maamora, CNESTEN, Rabat (Morocco); Radiations and Nuclear Systems Laboratory, University Abdelmalek Essaadi, Faculty of Sciences of Tetuan (Morocco); Merroun, O. [Radiations and Nuclear Systems Laboratory, University Abdelmalek Essaadi, Faculty of Sciences of Tetuan (Morocco); El Younoussi, C. [CEN-Maamora, CNESTEN, Rabat (Morocco); Radiations and Nuclear Systems Laboratory, University Abdelmalek Essaadi, Faculty of Sciences of Tetuan (Morocco); Htet, A. [CEN-Maamora, CNESTEN, Rabat (Morocco); Boukhal, H. [Radiations and Nuclear Systems Laboratory, University Abdelmalek Essaadi, Faculty of Sciences of Tetuan (Morocco); Chakir, E. [LRM/EPTN, Department of Physics, Faculty of Sciences, Kenitra (Morocco)

    2011-01-15

    Research highlights: The COOLOD/N2 and PARET/ANL codes were used for a steady-state thermal-hydraulic and safety analysis of the 2 MW TRIGA MARK II reactor located at the Nuclear Studies Center of Maamora (CENM), Morocco. The main objective of this study is to ensure the safety margins of different safety related parameters by steady-state calculations at full power level (2 MW). The most important conclusion is that all obtained values of DNBR, fuel center and surface temperature, cladding surface temperature and coolant temperature across the hottest channel are largely far to compromise safety of the reactor. - Abstract: The COOLOD/N2 and PARET/ANL codes were used for a steady-state thermal-hydraulic and safety analysis of the 2 MW TRIGA MARK II reactor located at the Nuclear Studies Center of Maamora (CENM), Morocco. In order to validate our PARET/ANL and COOLOD-N2 models, the fuel center temperature as function of core power was calculated and compared with the corresponding experimental values. The comparison indicates that the calculated values are in satisfactory agreement with the measurement. The main objective of this study is to ensure the safety margins of different safety related parameters by steady-state calculations at full power level (2 MW). Therefore, we have calculated the departure from nucleate boiling ratio (DNBR), fuel center and surface temperature, cladding surface temperature and coolant temperature profiles across the hottest channel. The most important conclusion is that all obtained values are largely far to compromise safety of the reactor.

  2. Neutronic and thermal-hydraulic analysis of new irradiation channels inside the Moroccan TRIGA Mark II research reactor core.

    Chham, E; El Bardouni, T; Benaalilou, K; Boukhal, H; El Bakkari, B; Boulaich, Y; El Younoussi, C; Nacir, B

    2016-10-01

    This study was conducted to improve the capacity of radioisotope production in the Moroccan TRIGA Mark II research reactor, which is considered as one of the most important applications of research reactors. The aim of this study is to enhance the utilization of TRIGA core in the field of neutron activation and ensure an economic use of the fuel. The main idea was to create an additional irradiation channel (IC) inside the core. For this purpose, three new core configurations are proposed, which differ according to the IC position in the core. Thermal neutron flux distribution and other neutronic safety parameters such as power peaking factors, excess reactivity, and control rods worth reactivity were calculated using the Monte Carlo N-Particle Transport (MCNP) code and neutron cross-section library based on ENDF/B-VII evaluation. The calculated thermal flux in the central thimble (CT) and in the added IC for the reconfigured core is compared with the thermal flux in the CT of the existing core, which is taken as a reference. The results show that all the obtained fluxes in CTs are very close to the reference value, while a remarkable difference is observed between the fluxes in the new ICs and reference. This difference depends on the position of IC in the reactor core. To demonstrate that the Moroccan TRIGA reactor could safely operate at 2MW, with new configurations based on new ICs, different safety-related thermal-hydraulic parameters were investigated. The PARET model was used in this study to verify whether the safety margins are met despite the new modifications of the core. The results show that it is possible to introduce new ICs safely in the reactor core, because the obtained values of the parameters are largely far from compromising the safety of the reactor. PMID:27552124

  3. Transient rod failure in a pulsing TRIGA Mark I reactor

    Full text: On July 7, 1970 the University of Texas at Austin TRIGA Mark I Pulsing Reactor experienced a failure of the transient control rod. Although no danger to personnel or damage to the reactor other than the pulse rod occurred, the failure was promptly reported to the USAEC regional compliance office. The first indication of an abnormal situation was unusual multiplication behavior during the first start-up of the day. As usual for steady state operation, the operator removed the transient rod and began to withdraw the shim and regulating rods. After partial withdrawal, he noticed that the count rate was not increasing as rapidly as was customary. While remaining at the console,the operator had a technician make a visual inspection of the core. The technician observed the transient drive rod was swinging freely in the pool and the poison section was detached. It was concluded, based on the indications of the.reactor instrumentation and visual inspection, that the transient control rod had broken off and remained in position in the core. The regulating and shim rods were inserted and the transient rod was manually cranked to the down position. The manual manipulation of the transient rod, instead of dropping the rod by gravity, was used so that the connecting rod could be reinserted in the control rod guide tube. The reactor core was then partially unloaded so that a critical mass was not present. The transient rod drive and connecting rod were removed from the pool. The poison section was retrieved from its position in the core by welding a tap to a long rod and tapping into the top of the poison section. Visual inspection of the poison section showed that the weld joining the male threads on the poison section to the main body of the control rod had failed. The threads remained screwed in the control rod drive shaft upon separation and the poison section remained fully inserted in the core. A new control rod was fabricated by Gulf General Atomic and shipped

  4. The research reactor TRIGA Mark II of the Johannes Gutenberg-University Mainz

    Hampel, Gabriele; Eberhardt, Klaus [Mainz Univ. (Germany). Inst. of Nuclear Chemistry

    2012-10-15

    The TRIGA Mark II research reactor of the University of Mainz was built in the 1960ies on the initiative of Fritz Strassmann, co-discoverer of the fission, at that time the director of the Institute for Inorganic and Nuclear Chemistry. On August 3{sup rd}, 1965 the TRIGA Mainz reached first criticality with the insertion of the 57{sup th} fuel element in the reactor core. Two years later, in April 1967, the Nobel Prize laureate Otto Hahn initiated the first of now more than 18,000 pulses at the official inauguration. Since then, the TRIGA Mainz has operated without failure about 200 days per year. The TRIGA Mainz can be operated in the steady state mode at power levels ranging up to 100 kW{sub th}, depending on the requirements of the different experiments. Pulse-mode operation is also possible. (orig.)

  5. The research reactor TRIGA Mark II of the Johannes Gutenberg-University Mainz

    The TRIGA Mark II research reactor of the University of Mainz was built in the 1960ies on the initiative of Fritz Strassmann, co-discoverer of the fission, at that time the director of the Institute for Inorganic and Nuclear Chemistry. On August 3rd, 1965 the TRIGA Mainz reached first criticality with the insertion of the 57th fuel element in the reactor core. Two years later, in April 1967, the Nobel Prize laureate Otto Hahn initiated the first of now more than 18,000 pulses at the official inauguration. Since then, the TRIGA Mainz has operated without failure about 200 days per year. The TRIGA Mainz can be operated in the steady state mode at power levels ranging up to 100 kWth, depending on the requirements of the different experiments. Pulse-mode operation is also possible. (orig.)

  6. The Application of Estimator Module for Controlling of TRIGA Mark II Reactor

    The estimator module application for control TRIGA Mark II reactor have been done. This application have purpose to help operator quickly and exactly when they control reactor reactivity. Which this module, if in the reactor will do experiment ( neutron activation, radioisotope production ect.) so the operator not need to calculate probability of reactivity changes. The result of estimator is close to measurements result (< 7 sec.), it is cause estimator can be used as equipment that can be used to help operation of TRIGA Mark II. (author)

  7. Power calibrations for TRIGA reactors

    The purpose of this paper is to establish a framework for the calorimetric power calibration of TRIGA reactors so that reliable results can be obtained with a precision better than ± 5%. Careful application of the same procedures has produced power calibration results that have been reproducible to ± 1.5%. The procedures are equally applicable to the Mark I, Mark II and Mark III reactors as well as to reactors having much larger reactor tanks and to TRIGA reactors capable of forced cooling up to 3 MW in some cases and 15 MW in another case. In the case of forced cooled TRIGA reactors, the calorimetric power calibration is applicable in the natural convection mode for these reactors using exactly the same procedures as are discussed below for the smaller TRIGA reactors (< 2 MW)

  8. TRIGA mark-II,III reactor safety re-evaluation

    For two years of 1990 and 1991, the safety of TRIGA Mk-II and III reactor has been re-evaluated. For this, domestic rules on research reactors has been reviewed, and as it was judged that standards on research reactors in USA is applicable to our ones it was evaluated whether TRIGA Mk-II and III reactors satisfy these standards. The site parameters and the environmental impacts during normal operation and hypothetical accident conditions have been analysed, and those parts for reactor facility and structure have been rewritten to fit SAR standard format based on the review of old SAR and maintenance manuals reflecting changes after the construction. Based on this re-evaluation, SAR, Technical Specifications, Radiation Emergency Plan, Environment Report, various procedures,etc. will be amended by the reactor management project. (Author)

  9. Triga mark-II,III reactor safety re-evaluation

    In order to revise safety analysis report of old TRIGA reactors, safety re-evaluation of these reactor was started for necessary parts. This report contains the first year results of the project scheduled for two years. The guide lines of safety re-evaluation was made by translating that of nuclear power plant from the view point of TRIGA reactor confirming the basic safety philosophy as much as possible. First of all, sections of reactor history and comparison with similar reactors are made, since the actual operation records, changes, any modification of similar reactors constructed after then, etc., are realistic and valuable data from the safety aspect of old reactor. For the effectiveness of nuclear analysis, a PC based analysis system using WIMS-D/4 and VENTURE was established, and a program for the natural convection cooling analysis of TRIGA reactor was developed. As a result of thermal-hydraulic analysis it was confirmed that the operation limit of fuel temperature set at 650 deg C without any logical reason is very close to the DNB limit. (Author)

  10. Decontamination and decommissioning project status of the TRIGA Mark-II and III reactors in Korea

    The decontamination and decommissioning (D and D) project of the TRIGA Mark-II and Mark-III was started in January 1997, after their shutdown in 1995 due to their life and the operation of a new research reactor, HANARO, at the KAERI site in Taejon. Preparation of the decommissioning plan and environmental impact assessment, and setting up of licensing procedure and documentation for the project were performed in 1997. At the end of 1997, Hyundai Engineering Company (HEC) was selected as the main contractor to do design and licensing documentation for the D and D of both reactors. British Nuclear Fuels Plc. (BNFL) was the technical assisting partner to Heck. Licensing documents were submitted to the Ministry of Science and Technology (MOST) at the end of 1998. And the Korea Institute of Nuclear Safety (KINS) is reviewing the documents. Practical work of the D and D will start at the end of 1999 upon the government issues the license. In the meantime, July 1998, all spent fuels from the TRIGA Mark-II and III were safely transported to the US. The foremost part of the D and D work will be the TRIGA Mark-III reactor hall that will be used as a temporary storage of radioactive waste produced during the D and D work, and followed by the TRIGA Mark-II and auxiliary facilities. This paper summarizes the current status and future plans for the D and D work. (author)

  11. Determination of neutronic fluxes in research nuclear reactor of Triga Mark I and WWRS types

    In this paper is presented the determination of the thermal, epithermal and fast neutron fluxes, using neutron activation analysis technique, for two research nuclear reactors of different design: the Triga Mark I reactor was designed by Gulf General Atomic Co in USA and the WWRS reactor was designed in the URSS, both in the 50's years. (Author)

  12. Measuring temperature coefficient of TRIGA MARK I reactor by noise analysis

    The transfer function of TRIGA MARK I Reactor is measured at power zero (5w) and power 118Kw, in the frequency range of 0.02 to 0.5 rd/s. The method of intercorrelation between a pseudostochasticbinary signal is used. A simple dynamic model of the reactor is developed and the coefficient of temperature is estimated

  13. The startup tests for TRIGA Mark II at the Institute for Nuclear Energy

    This paper briefly describes the start-up tests for TRIGA Mark-II at the Institute for Nuclear Energy and some of the problems during the construction. This Report consists of three parts: 1. Shield Construction and Installation of ITU-TRR Components. 2. Start-up Experiments. 3. Experience Gained in Operation and Maintenance

  14. Experience in the operation and maintenance of the Austrian TRIGA Mark II reactor

    The Austrian TRIGA Mark II reactor ia in operation since March 1962. The reactor instrumentation, core design and irradiation facilities and operation are described. Besides steady state power and pulse operation, square wave operation has been installed 1968, allowing power squares up to 750 kW. A Survey of reactor operation and experiments is given

  15. Monte Carlo analysis of Musashi TRIGA mark II reactor core

    Matsumoto, Tetsuo [Atomic Energy Research Laboratory, Musashi Institute of Technology, Kawasaki, Kanagawa (Japan)

    1999-08-01

    The analysis of the TRIGA-II core at the Musashi Institute of Technology Research Reactor (Musashi reactor, 100 kW) was performed by the three-dimensional continuous-energy Monte Carlo code (MCNP4A). Effective multiplication factors (k{sub eff}) for the several fuel-loading patterns including the initial core criticality experiment, the fuel element and control rod reactivity worth as well as the neutron flux measurements were used in the validation process of the physical model and neutron cross section data from the ENDF/B-V evaluation. The calculated k{sub eff} overestimated the experimental data by about 1.0%{delta}k/k for both the initial core and the several fuel-loading arrangements. The calculated reactivity worths of control rod and fuel element agree well the measured ones within the uncertainties. The comparison of neutron flux distribution was consistent with the experimental ones which were measured by activation methods at the sample irradiation tubes. All in all, the agreement between the MCNP predictions and the experimentally determined values is good, which indicated that the Monte Carlo model is enough to simulate the Musashi TRIGA-II reactor core. (author)

  16. Numerical simulation of non-steady state neutron kinetics of the TRIGA Mark II reactor Vienna

    Riede, Julia

    2013-01-01

    This paper presents an algorithm for numerical simulations of non-steady states of the TRIGA MARK II reactor in Vienna, Austria. The primary focus of this work has been the development of an algorithm which provides time series of integral neutron flux after reactivity changes introduced by perturbations without the usage of thermal-hydraulic / neutronic numerical code systems for the TRIGA reactor in Vienna, Austria. The algorithm presented takes into account both external reactivity changes as well as internal reactivity changes caused by feedback mechanisms like effects caused by temperature changes of the fuel and poisoning effects. The resulting time series have been compared to experimental results.

  17. Current research projects at the Austrian TRIGA Mark II. Location of failed fuel elements in Austrian TRIGA Mark II

    The system developed at the Atominstitut monitors the radioactive Krypton- and Xenon nuclides in the primary water circuitry and allows selective control of any fuel element for its fission gas release. A suspected fuel element is enclosed in an underwater capsule attached in the reactor tank. Water is pumped along the fuel element to a vacuum degasser where the gases are separated from the tank water. The degassed water is returned to the reactor pool while the gases are pumped to a very sensitive proportional counter. The fuel elements of the TRIGA core were checked by the described procedure

  18. Research programs carried out at the TRIGA Mark II reactor Vienna

    Research programs carried out at the TRIGA Mark II reactor Vienna are reported in the presentation. Many of the research programs presented at the previous TRIGA Conference in Istambul have been completed and a number of new research programs have been started some of them in cooperation or with support of the International Atomic Energy Agency. The most important project titles are: (1) Development of a laser surveillance system for spent fuel pools, (2) Identification of LWR fuel bundeles by magnetic scanning, and (3) Test of fission chambers in intense gamma fields. A damaged TRIGA fuel rod which was stored for more than 20 years has been cut in October 1983 into several pieces. The U-Zr-H samples are now being used for burn-up calibration as they contain only Cs-137. (orig.)

  19. Activation of TRIGA Mark II research reactor concrete shield

    To determine neutron activation inside the TRIGA research reactor concrete body a special sample-holder for irradiation inside horizontal channel was developed and tested. In the sample-holder various samples can be irradiated at different concrete shielding depths. In this paper the description of the sample-holder, experiment conditions and results of long-lived activation measurements are given. Long-lived neutron-induced gamma-ray-emitting radioactive nuclides in the samples were measured with HPGe detector. The most active long-lived radioactive nuclides in ordinary concrete samples were found to be 60Co and 152Eu and in barytes concrete samples 60Co, 152Eu and 133Ba. Measured activity density of all nuclides was found to decrease almost linearly with depth in logarithmic scale. (author)

  20. Computer code for the thermal-hydraulic analysis of ITU TRIGA Mark-II reactor

    Istanbul Technical University (ITU) TRIGA Mark-II reactor core consists of ninety vertical cylindrical elements located in five rings. Sixty-nine of them are fuel elements. The reactor is operated and cooled with natural convection by pool water, which is also cooled and purified in external coolant circuits by forced convection. This characteristic leads to consider both the natural and forced convection heat transfer in a 'porous-medium analysis'. The safety analysis of the reactor requires a thermal-hydraulic model of the reactor to determine the thermal-hydraulic parameters in each mode of operation. In this study, a computer code cooled TRIGA-PM (TRIGA - Porous Medium) for the thermal-hydraulic analysis of ITU is considered. TRIGA Mark-II reactor code has been developed to obtain velocity, pressure and temperature distributions in the reactor pool as a function of core design parameters and pool configuration. The code is a transient, thermal-hydraulic code and requires geometric and physical modelling parameters. In the model, although the reactor is considered as only porous medium, the other part of the reactor pool is considered partly as continuum and partly as porous medium. COMMIX-1C code is used for the benchmark purpose of TRIGA-PM code. For the normal operating conditions of the reactor, estimations of TRIGA-PM are in good agreement with those of COMMIX-1C. After some more improvements, this code will be employed for the estimation of LOCA scenario, which can not be analyses by COMMIX-1C and the other multi-purpose codes, considering a break at one of the beam tubes of the reactor

  1. Immobilization of ion exchange radioactive resins of the TRIGA Mark III nuclear reactor; Inmovilizacion de resinas de intercambio ionico radiactivas del reactor nuclear Triga Mark III

    Garcia M, H.; Emeterio H, M.; Canizal S, C. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, C.P. 11801 Mexico D.F. (Mexico)

    2000-07-01

    This work has the objective to develop the process and to define the agglutinating material which allows the immobilization of the ion exchange radioactive resins coming from the TRIGA Mark III nuclear reactor contaminated with Ba-133, Co-60, Cs-137, Eu-152, and Mn-54 through the behavior analysis of different immobilization agents such as: bitumens, cement and polyester resin. According to the International Standardization the archetype samples were observed with the following tests: determination of free liquid, leaching, charge resistance, biodegradation, irradiation, thermal cycle, burned resistance. Generally all the tests were satisfactorily achieved, for each agent. Therefore, the polyester resin could be considered as the main immobilizing. (Author)

  2. Using TRIGA Mark II research reactor for irradiation with thermal neutrons

    Kolšek, Aljaž, E-mail: aljaz.kolsek@gmail.com; Radulović, Vladimir, E-mail: vladimir.radulovic@ijs.si; Trkov, Andrej, E-mail: andrej.trkov@ijs.si; Snoj, Luka, E-mail: luka.snoj@ijs.si

    2015-03-15

    Highlights: • Monte Carlo N-Particle Transport Code was used to design and perform calculations. • Characterization of the TRIGA Mark II ex-core irradiation facilities was performed. • The irradiation device was designed in the TRIGA irradiation channel. • The use of the device improves the fraction of thermal neutron flux by 390%. - Abstract: Recently a series of test irradiations was performed at the JSI TRIGA Mark II reactor for the Fission Track-Thermoionization Mass Spectrometry (FT-TIMS) method, which requires a well thermalized neutron spectrum for sample irradiation. For this purpose the Monte Carlo N-Particle Transport Code (MCNP5) was used to computationally support the design of an irradiation device inside the TRIGA model and to support the actual measurements by calculating the neutron fluxes inside the major ex-core irradiation facilities. The irradiation device, filled with heavy water, was designed and optimized inside the Thermal Column and the additional moderation was placed inside the Elevated Piercing Port. The use of the device improves the ratio of thermal neutron flux to the sum of epithermal and fast neutron flux inside the Thermal Column Port by 390% and achieves the desired thermal neutron fluence of 10{sup 15} neutrons/cm{sup 2} in irradiation time of 20 h.

  3. Using TRIGA Mark II research reactor for irradiation with thermal neutrons

    Highlights: • Monte Carlo N-Particle Transport Code was used to design and perform calculations. • Characterization of the TRIGA Mark II ex-core irradiation facilities was performed. • The irradiation device was designed in the TRIGA irradiation channel. • The use of the device improves the fraction of thermal neutron flux by 390%. - Abstract: Recently a series of test irradiations was performed at the JSI TRIGA Mark II reactor for the Fission Track-Thermoionization Mass Spectrometry (FT-TIMS) method, which requires a well thermalized neutron spectrum for sample irradiation. For this purpose the Monte Carlo N-Particle Transport Code (MCNP5) was used to computationally support the design of an irradiation device inside the TRIGA model and to support the actual measurements by calculating the neutron fluxes inside the major ex-core irradiation facilities. The irradiation device, filled with heavy water, was designed and optimized inside the Thermal Column and the additional moderation was placed inside the Elevated Piercing Port. The use of the device improves the ratio of thermal neutron flux to the sum of epithermal and fast neutron flux inside the Thermal Column Port by 390% and achieves the desired thermal neutron fluence of 1015 neutrons/cm2 in irradiation time of 20 h

  4. Decontamination and decommissioning project status of the TRIGA Mark II and III in Korea

    TRIGA Mark-II, the first research reactor in Korea, has operated since 1962, and the second one, TRIGA Mark-III since 1972. Both of them had their operation phased out in 1995 due to their lives and operation of the new research reactor, HANARO (High-flux Advanced Neutron Application Reactor) at the Korea Atomic Energy Institute (KAERI) in Taejon. Decontamination and decommissioning (D and D) project of TRIGA Mark-II and Mark-III was started in January 1997 and will be completed in December 2002. The first year of the project, work was performed in preparation of the decommissioning plan, start of the environmental impact assessment and setup licensing procedure and documentation for the project with cooperation of Korea Institute of Nuclear Safety (KINS). Hyundai Engineering Company (HEC) is the main contractor to do design and licensing documentation for the D and D of both reactors. British Nuclear Fuels plc (BNFL) is the technical assisting partner of HEC. The decommissioning plan document was submitted to the Ministry of Since and Technology (MOST) for the decommissioning license in December 1998, and it expecting to be issued a license in mid 1999. The goal of this project is to release the reactor site and buildings as an unrestricted area. This paper summarizes current status and future plan for the D and D project. (author)

  5. Decontamination and decommissioning project status of the TRIGA Mark II and III in Korea

    Paik, S.T.; Park, S.K.; Chung, K.W.; Chung, U.S.; Jung, K.J. [Nuclear Fuel Cycle Development Group, Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-08-01

    TRIGA Mark-II, the first research reactor in Korea, has operated since 1962, and the second one, TRIGA Mark-III since 1972. Both of them had their operation phased out in 1995 due to their lives and operation of the new research reactor, HANARO (High-flux Advanced Neutron Application Reactor) at the Korea Atomic Energy Institute (KAERI) in Taejon. Decontamination and decommissioning (D and D) project of TRIGA Mark-II and Mark-III was started in January 1997 and will be completed in December 2002. The first year of the project, work was performed in preparation of the decommissioning plan, start of the environmental impact assessment and setup licensing procedure and documentation for the project with cooperation of Korea Institute of Nuclear Safety (KINS). Hyundai Engineering Company (HEC) is the main contractor to do design and licensing documentation for the D and D of both reactors. British Nuclear Fuels plc (BNFL) is the technical assisting partner of HEC. The decommissioning plan document was submitted to the Ministry of Since and Technology (MOST) for the decommissioning license in December 1998, and it expecting to be issued a license in mid 1999. The goal of this project is to release the reactor site and buildings as an unrestricted area. This paper summarizes current status and future plan for the D and D project. (author)

  6. Decontamination and decommissioning project status of the TRIGA mark-2±3 research reactors

    TRIGA Mark-II, the first research reactor in Korea, has operated since 1962, and the second one, TRIGA Mark-III since 1972. Both of them had their operation phased out in 1995 due to their lives and operation of the new research reactor, HANARO at the Korea Atomic Energy Research Institute (KAERI) in Taejeon. Decontamination and decommissioning (D and D) project of the TRIGA Mark-II and Mark-III was started in January 1997 and will be completed in December 2002. In the first year of the project, work was performed in preparation of the decommissioning plan, start of the environmental impact assessment and setup licensing procedure and documentation for the project with cooperation of Korea Institute of Nuclear Safety (KINS). In 1998, Hyundai Engineering Company (HEC) is the main contractor to do design and licensing documentation for the D and D of both reactors. British Nuclear Fuels plc (BNFL) is technical assisting partner of HEC. The decommissioning plan document was submitted to the Ministry of Science and Technology (MOST) for the decommissioning license in December 1998, and it expecting to be issued a license at the end of September 1999. The goal of this project is to release the reactor site and buildings as an unrestricted area. This paper summarizes current status and future plan for the D and D project

  7. New practical exercises at the JSI TRIGA Mark II reactor

    Since the 1990s the Jozef Stefan Institute (JSI) TRIGA reactor has been extensively used for performing training in experimental reactor physics. In 2012 we upgraded some of the existing and introduced some new exercises. The pulse mode operation exercise was upgraded by installation of new data acquisition system. The critical experiment exercise was improved by adding a new detector inside the reactor core and changing the data acquisition system. Now we monitor neutron population with two independent fission chambers on different locations. In the past the void reactivity coefficient exercise was performed by inserting Al tube into various positions in the reactor core and measuring the corresponding reactivity changes. In order to make the exercise more realistic, we installed a pneumatic system for generating air bubbles just below the core. The aim of the exercise is to measure reactivity changes versus flow rate and air bubble position. The second new exercise was measurement of water activation. In this exercise we installed special system which pumps the water through the core at a constant flow rate to the reactor platform, where the water activity is measured. The purpose of the exercise is to measure the 16N and 19O gamma line intensity and dose rate versus reactor power. The third new exercise, named in core flux mapping, was performed by measuring the axial fission rate distribution at various radial positions in the core. We used CEA - developed mini fission chambers and a special home developed system for moving the fission chamber in axial direction and measuring the count rate versus fission chamber position. In the paper the experiments are presented together with results. (author)

  8. The possibility of gamma ray sterilization by using ITU TRIGA Mark II reactor

    Gamma rays are one of the effective method for sterilization which is preferred for a long time. Generally Co-60 radioisotope sources betatrons or accelerators are used for the sterilization. In this work, it was aimed to find the possibilities of the sterilization by gamma rays obtained in ITU TRIGA Mark-II radial tube. Radiation dosages are measured in the radial tube and several medical products are irradiated. Irradiation is arranged according to the desired dosages. Irradiated sterilized goods (mainly medical products) tested and checked at the Governmental Medical Health Center and results compared with literature. It can be seen that this kind of irradiation is a good tool for sterilization. Unfortunately, because of the stability of the radial tube and impracticality of the system it is rather difficult to compete with industrial system using Co-60 and accelerators. Nevertheless, this type of irradiation is also applicable for the purpose of the sterilization by using ITU TRIGA Mark II. (author)

  9. Fuel Management Strategies for a Possible Future LEU Core of a TRIGA Mark II Vienna

    Khan, R.; Villa, M.; Steinhauser, G.; Boeck, H. [Vienna University of Technology-Atominstitut (Austria)

    2011-07-01

    The Vienna University of Technology/Atominstitut (VUT/ATI) operates a TRIGA Mark II research reactor. It is operated with a completely mixed core of three different types of fuel. Due to the US fuel return program, the ATI have to return its High Enriched Uranium (HEU) fuel latest by 2019. As an alternate, the Low Enrich Uranium (LEU) fuel is under consideration. The detailed results of the core conversion study are presented at the RRFM 2011 conference. This paper describes the burn up calculations of the new fuel to predict the future burn up behavior and core life time. It also develops an effective and optimized fuel management strategy for a possible future operation of the TRIGA Mark II with a LEU core. This work is performed by the combination of MCNP5 and diffusion based neutronics code TRIGLAV. (author)

  10. Fuel Management Strategies for a Possible Future LEU Core of a TRIGA Mark II Vienna

    The Vienna University of Technology/Atominstitut (VUT/ATI) operates a TRIGA Mark II research reactor. It is operated with a completely mixed core of three different types of fuel. Due to the US fuel return program, the ATI have to return its High Enriched Uranium (HEU) fuel latest by 2019. As an alternate, the Low Enrich Uranium (LEU) fuel is under consideration. The detailed results of the core conversion study are presented at the RRFM 2011 conference. This paper describes the burn up calculations of the new fuel to predict the future burn up behavior and core life time. It also develops an effective and optimized fuel management strategy for a possible future operation of the TRIGA Mark II with a LEU core. This work is performed by the combination of MCNP5 and diffusion based neutronics code TRIGLAV. (author)

  11. Radioactive waste management plan for TRIGA Mark-II and III deecommissioning activities

    A radioavtive waste management plan was set-up for the decontamination and decommissioning of the TRIGA Mark II and III. They were categorized by the radioactivity and by the physical properties, solid , liquid, gaseous radioactive waste. The gaseous waste will be treated by the existing filtration equipment. The use of temporary containment with a portable ventilation system is planned during the dismantling work where there is the potential to generate particles. Liquid radioactive waste will be concentrated by a natural evaporator and the concentrate will then be solidified by using cement. All of the solid wastes will be packed in a 4 m3 ISO container and stored until a final disposal facility for low- and intermediate-level radioactive waste is operational. This paper covers a general plan of the radioactive waste management during the TRIGA Mark-II and III decontamination and decommissioning activities. (author)

  12. Modification of the radial beam port of ITU TRIGA Mark II research reactor for BNCT applications

    This paper aims to describe the modification of the radial beam port of ITU (İstanbul Technical University) TRIGA Mark II research reactor for BNCT applications. Radial beam port is modified with Polyethylene and Cerrobend collimators. Neutron flux values are measured by neutron activation analysis (Au–Cd foils). Experimental results are verified with Monte Carlo results. The results of neutron/photon spectrum, thermal/epithermal neutron flux, fast group photon fluence and change of the neutron fluxes with the beam port length are presented. - Highlights: • Using MCNP5, radial beam port of ITU TRIGA Mark II research reactor is modified. • Polyethylene and Cerrobend collimators are used to modify the beam port. • Results of two-group neutron/photon flux are presented. • Monte Carlo results are compared with experimental results

  13. Applicable regulations and development of surveillance experiments of criticality approach in the TRIGA III Mark reactor

    In the procedure elaborated to repair the vessel of TRIGA III Mark reactor is required to move toward two tanks of temporal storage the fuel elements which are in operation and the spent fuel elements which are in decay inside the reactor pool. The National Commission of Nuclear Safety and Safeguards (CNSNS) has requested as protection measure that it is carried out a surveillance of the criticality approach of the temporal storages. This work determines the main regulation aspects that entails an experiment of criticality approach, moreover, informing about the results obtained in the developing of this experiments. The regulation aspects are not exclusives for this work in the TRIGA Mark III reactor but they also apply toward any assembling of fissile material. (Author)

  14. Visual examination program of the TRIGA Mark II reactor Vienna with the nuclear underwater telescope

    The visual inspection programm carried out during a three month shut-period at the TRIGA Mark II reactor Vienna is described. Optical inspection of all welds inside the reactor tank was carried out with an underwater telescope developed by the Central Research Institute of Physics, Budapest, Hungary. It is shown that even after 23 years of reactor operation all tank internals were found to be in good condition and minor defects can be easily repaired by remote handling tools. (Author)

  15. Data base formation for important components of reactor TRIGA MARK II

    The paper represents specific data base formation for reactor TRIGA MARK II in Podgorica. Reactor operation data from year 1985 to 1990 were collected. Two groups of collected data were formed. The first group includes components data and the second group covers data of reactor scrams. Time related and demand related models were used for data evaluation. Parameters were estimated by classical method. Similar data bases are useful everywhere where components unavailabilities may have severe drawback. (author)

  16. Analysis of JSI TRIGA MARK II reactor physical parameters calculated with TRIPOLI and MCNP.

    Henry, R; Tiselj, I; Snoj, L

    2015-03-01

    New computational model of the JSI TRIGA Mark II research reactor was built for TRIPOLI computer code and compared with existing MCNP code model. The same modelling assumptions were used in order to check the differences of the mathematical models of both Monte Carlo codes. Differences between the TRIPOLI and MCNP predictions of keff were up to 100pcm. Further validation was performed with analyses of the normalized reaction rates and computations of kinetic parameters for various core configurations. PMID:25576735

  17. Characterization of the TRIGA Mark II reactor full-power steady state

    Cammi, Antonio; Zanetti, Matteo; Chiesa, Davide; Clemenza, Massimiliano; Pozzi, Stefano; Previtali, Ezio; Sisti, Monica; Magrotti, Giovanni; Prata, Michele; Salvini, Andrea

    2015-01-01

    In this work, the characterization of the full-power steady state of the TRIGA Mark II nuclear reactor of the University of Pavia is performed by coupling Monte Carlo (MC) simulation for neutronics with "Multiphysics" model for thermal-hydraulics. Neutronic analyses have been performed starting from a MC model of the entire reactor system, based on the MCNP5 code, that was already validated in fresh fuel and zero-power configuration (in which thermal effects are negligible) using the availabl...

  18. 3-D flux distribution and criticality calculation of TRIGA Mark-II

    In this work, the static calculation of the (I.T.U. TRIGA Mark-II) flux distribution has been made. The three dimensional, r-θ-z, representation of the core has been used. In this representation, for different configuration, the flux distribution has been calculated depending on two group theory. The thermal-hydraulics, the poisoning effects have been ignored. The calculations have been made by using the three dimensional and multigroup code CAN. (author)

  19. Use of the TRIGA Mark III as a simulator for the Tokamak Fusion Test Reactor (TFTR)

    The Exposure-Room feature on the TRIGA Mark III reactor offers the possibility for experiments which simulate the expected dose to components produced in pulses from the TFTR fusion reactor. Although the TRIGA pulse is considerably shorter and the TRIGA fast-neutron spectrum is considerably softer, the fast-neutron fluence represents a good match to that expected from TFTR, and the thermal-neutron fluence and gamma-ray dose from the TRIGA constitute a considerable overtest compared to that expected from TFTR. An experiment is underway which involves irradiating a prototype TFTR cyropump in the Exposure-Room facility. The cryopump is pulsed twice, once before and once after deuterium is admitted to the pump. The object is to determine whether the radiation has any desorptive effect on the deuterium in the pump. Care must be taken to prevent conditions under which the deuterium might explode, or under which oxygen condensed in the presence of the liquid nitrogen or liquid helium might constitute a combustion hazard. (author)

  20. Benchmark analysis of the TRIGA MARK II research reactor using Monte Carlo techniques

    This study deals with the neutronic analysis of the current core configuration of a 3-MW TRIGA MARK II research reactor at Atomic Energy Research Establishment (AERE), Savar, Dhaka, Bangladesh and validation of the results by benchmarking with the experimental, operational and available Final Safety Analysis Report (FSAR) values. The 3-D continuous-energy Monte Carlo code MCNP4C was used to develop a versatile and accurate full-core model of the TRIGA core. The model represents in detail all components of the core with literally no physical approximation. All fresh fuel and control elements as well as the vicinity of the core were precisely described. Continuous energy cross-section data from ENDF/B-VI and ENDF/B-V and S(α,β) scattering functions from the ENDF/B-VI library were used. The consistency and accuracy of both the Monte Carlo simulation and neutron transport physics was established by benchmarking the TRIGA experiments. The effective multiplication factor, power distribution and peaking factors, neutron flux distribution, and reactivity experiments comprising control rod worths, critical rod height, excess reactivity and shutdown margin were used in the validation process. The MCNP predictions and the experimentally determined values are found to be in very good agreement, which indicates that the simulation of TRIGA reactor is treated adequately

  1. Over Twenty Years Of Experience In ITU TRIGA MARK-II Reactor

    I.T.U. TRIGA MARK-II Training and Research Reactor, rated at 250 kW steady-state and 1200 MW pulsing power is the only research and training reactor owned and operated by a university in Turkey. Reactor has been operating since March 11, 1979; therefore the reactor has been operating successfully for more than twenty years. Over the twenty years of operation: - The tangential beam tube was equipped with a neutron radiography facility, which consists of a divergent collimator and exposure room; - A computerized data acquisition system was designed and installed such that all parameters of the reactor, which are observed from the console, could be monitored both in normal and pulse operations; - An electrical power calibration system was built for the thermal power calibration of the reactor; - Publications related with I.T.U. TRIGA MARK-II Training and Research Reactor are listed in Appendix; - Two majors undesired shutdown occurred; - The I.T.U. TRIGA MARK-II Training and Research Reactor is still in operation at the moment. (authors)

  2. Evaluation of nuclear safety measurements in ITU TRIGA Mark-II Reactor

    For the evaluation of the radiation measurements all the records made during over 20 years of operation of ITU TRIGA Mark-II Training and Research Reactor which has 250 kW full power are considered. In addition to the routine measurements, monitoring of the radiation levels in special places in the reactor are evaluated also which can be important for special working conditions. For the evaluation of the personnel monitoring, all the records are investigated for personnel exposed to radiation working at the ITU TRIGA Mark-II Training and Research Reactor. Determinations in air and water samples are tabulated for the reactor. Water samples have been taken from two cooling systems and the cooling tower. Air samples have been taken from the filter of ventilation system. Results of all the radiation measurements are evaluated according to the maximum permissible levels from the point of view of nuclear safety and public safety. One can conclude that ITU TRIGA Mark-II Training and Research Reactor has been operated in safe conditions since the reactor criticality date on 11 March 1979. (authors)

  3. Simulation of TRIGA Mark II Benchmark Experiment using WIMSD4 and CITATION codes; Simulacao com WIMSD4 e CITATION do Triga Mark II benchmark experiment

    Dalle, Hugo Moura [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil); Pereira, Claubia [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear

    2000-07-01

    This paper presents a simulation of the TRIGA Mark II Benchmark Experiment, Part I: Steady-State Operation and is part of the calculation methodology validation developed to the neutronic calculation of the CDTN's TRIGA IPR - R1 reactor. A version of the WIMSD4, obtained in the Centro de Tecnologia Nuclear, in Cuba, was used in the cells calculation. In the core calculations was adopted the diffusion code CITATION. Was adopted a 3D representation of the core and the calculations were carried out at two energy groups. Many of the experiments were simulated, including, K{sub eff}, control rods reactivity worth, fuel elements reactivity worth distribution and the fuel temperature reactivity coefficient. The comparison of the obtained results, with the experimental results, shows differences in the range of the accuracy of the measurements, to the control rods worth and fuel temperature reactivity coefficient, or on an acceptable range, following the literature, to the K{sub eff} and fuel elements reactivity worth distribution and the fuel temperature reactivity coefficient. The comparison of the obtained results, with the experimental. results, shows differences in the range of the accuracy of the measurements, to the control rods worth and fuel temperature reactivity coefficient, or in an acceptable range, following the literature, to the K{sub eff} and fuel elements reactivity worth distribution. (author)

  4. On Line Measurement of Reactivity Worth of TRIGA Mark-II Research Reactor Control Rods

    Nusrat Jahan

    2011-09-01

    Full Text Available The reactivity worth measurement system for control rods of the TRIGA MARK-II research reactor of Bangladesh has been design and developed. The theory of the kinetic technique of measuring reactivity has been used by this measurement system. The system comprises of indigenous hardware and software for online acquisition of neutron flux signals from reactor console and then computes the reactivity worth accordingly. Here for the TRIGA MARK-II research reactor, the reactivity measurement system was implemented with a dedicated circuit assembly and a conventional personal computer. A high-level Visual Basic real-time programming has been developed for data acquisition, reactivity calculation, online display (numerically as well as graphically, saving data, etc. To measure reactivity worth of TRIGA reactor control rods the rod drop experimental technique has been adopted. The results of tests experiments, carried out with the rod drop method for measuring various reactivity worth of control rods have been presented in the paper. A comparison between this results with the results using period method and that of computation method, demonstrated that the response of this reactivity measurement system is fast enough to monitor and measure the safety-related reactivity and power excursions in the reactor.

  5. Neutron spectra at two beam ports of a TRIGA Mark III reactor loaded with HEU fuel

    The neutron spectra have been measured in two beam ports, one radial and another tangential, of the TRIGA Mark III nuclear reactor from the National Institute of Nuclear Research in Mexico. Measurements were carried out with the reactor core loaded with high enriched uranium fuel. Two reactor powers, 5 and 10 W, were used during neutron spectra measurements using a Bonner sphere spectrometer with a 6LiI(Eu) scintillator and 2, 3, 5, 8, 10 and 12 in.-diameter high-density polyethylene spheres. The neutron spectra were unfolded using the NSDUAZ unfolding code. For each spectrum total flux, mean energy and ambient dose equivalent were determined. Measured spectra show fission, epithermal and thermal neutrons, being harder in the radial beam port. - Highlights: • Neutron spectra of a TRIGA reactor were measured. • The reactor core is loaded with HEU. • The spectra were measured at two reactor beam ports. • Measurements were carried out at 5 and 10 W

  6. Experimental power density distribution benchmark in the TRIGA Mark II reactor

    Snoj, L.; Stancar, Z.; Radulovic, V.; Podvratnik, M.; Zerovnik, G.; Trkov, A. [Josef Stefan Inst., Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Barbot, L.; Domergue, C.; Destouches, C. [CEA DEN, DER, Instrumentation Sensors and Dosimetry laboratory Cadarache, F-13108 Saint-Paul-Lez-Durance (France)

    2012-07-01

    In order to improve the power calibration process and to benchmark the existing computational model of the TRIGA Mark II reactor at the Josef Stefan Inst. (JSI), a bilateral project was started as part of the agreement between the French Commissariat a l'energie atomique et aux energies alternatives (CEA) and the Ministry of higher education, science and technology of Slovenia. One of the objectives of the project was to analyze and improve the power calibration process of the JSI TRIGA reactor (procedural improvement and uncertainty reduction) by using absolutely calibrated CEA fission chambers (FCs). This is one of the few available power density distribution benchmarks for testing not only the fission rate distribution but also the absolute values of the fission rates. Our preliminary calculations indicate that the total experimental uncertainty of the measured reaction rate is sufficiently low that the experiments could be considered as benchmark experiments. (authors)

  7. Safety analysis calculations for a mixed and full FLIP core in a TRIGA Mark II

    The Oregon State TRIGA Reactor will be reloading with FLIP fuel in August 1976. As we are the first Mark II TRIGA with a circular grid pattern and graphite reflector to utilize FLIP fuel, the safety analysis calculations performed at other facilities using FLIP were only of limited use to us. A multigroup, multiregion, one-dimensional diffusion theory code was used to calculate power densities in six different operational cores - mixed to full FLIP. Pulsing characteristics were obtained from a computer code based on point kinetics, with adiabatic heating of the fuel, linear temperature dependence of the specific heat, and prompt fuel temperature feedback coefficient. The results of all pertinent calculations will be presented. (author)

  8. Experience in operation and maintenance of the TRIGA Mark II reactor at the University of Pavia

    Experience in the operation and maintenance of the 250 kW steady state/250 MW pulsed TRIGA Mark II Reactor of the University of Pavia in the past two years is reported. Data for the reactor utilization and of Health Physics activity are also presented. Since the Second European Conference of TRIGA Reactor Users in 1972, reactor operation continued normally. No major troubles occurred during this time except for rotary specimen rack rotation. Maintenance of reactor facilities, including the substitution of the rotary specimen rack with a new one manufactured on-site is described. In June 1974 measurements of fluxes in the thermal column, with most of the graphite elements removed, were carried out in order to install a neutron converter in thermal column. Some results of fluxes and cadmium ratio values are reported. A description of the converter facility set up is given. (U.S.)

  9. The fuel element situation at the TRIGA mark II reactor Vienna

    The fuel history, spent fuel storage situation and recent problems covering the period from 1962 until 1.6.2001 were reviewed. After almost 40 years of TRIGA MARK II reactor Vienna operation, it must be mentioned that the experience with TRIGA fuel elements was and is excellent. During this period only 9 fuel elements had to be permanently be removed from the core and 57 fuel elements from the initial start-up are still used in the core. A careful fuel management and a frequent fuel inspection is of most importance, fuel elements should be moved at least two-times a year from their core position to check free movement and a 180 deg. rotation of the fuel element is also recommended (nevyjel)

  10. Experience with service and maintenance of a TRIGA Mark II reactor after 24 years of operation

    The maintenance work and the inspection program carried out at the TRIGA Mark II reactor Vienna after more than two decades of reactor operation is described. With the help of a special underwater telescope all surfaces inside the reactor tank were inspected visually and two beam tubes were inspected with an endoscope. A new water purification loop was installed in 1985, which was followed by a new primary coolant circuit in 1986. The reactor bridge was dismantled, all control rod drives were serviced and some components replaced. As a result of this program it was observed that a TRIGA reactor can be serviced, improved and backfitted even after 24 years of operation with minor efforts. (author)

  11. Experimental power density distribution benchmark in the TRIGA Mark II reactor

    In order to improve the power calibration process and to benchmark the existing computational model of the TRIGA Mark II reactor at the Josef Stefan Inst. (JSI), a bilateral project was started as part of the agreement between the French Commissariat a l'energie atomique et aux energies alternatives (CEA) and the Ministry of higher education, science and technology of Slovenia. One of the objectives of the project was to analyze and improve the power calibration process of the JSI TRIGA reactor (procedural improvement and uncertainty reduction) by using absolutely calibrated CEA fission chambers (FCs). This is one of the few available power density distribution benchmarks for testing not only the fission rate distribution but also the absolute values of the fission rates. Our preliminary calculations indicate that the total experimental uncertainty of the measured reaction rate is sufficiently low that the experiments could be considered as benchmark experiments. (authors)

  12. A parametric thermal-hydraulic analysis of I.T.U. TRIGA Mark-II reactor

    In this study, a transient, one-dimensional thermal-hydraulic subchannel analysis for I.T.U. TRIGA Mark-II reactor was employed. The cooling of this reactor is based on natural convection; however, mixed convection is considered in modeling in order to enhance the capability of the computer code. After the continuity, conservation of energy, momentum balance equations for coolant in axial direction and heat conduction equation for fuel rod in radial direction had been written, they were discretized by using the control volume approach to obtain a set of algebraic equations. By the aid of discretized continuity and momentum balance equations, a pressure correction equation was derived. Then, a FORTRAN program called TRIGATH (TRIGA Thermal-Hydraulics) has been developed to solve this set of algebraic equations by using SIMPLE algorithm. As a result, the temperature distributions of the coolant and fuel rods as well as the velocity and pressure distributions of the coolant have been estimated. (authors)

  13. Optimization of a Potential New Core of the TRIGA Mark II Reactor Vienna

    Khan, R.; Villa, M.; Bock, H.; Abele, H.; Steinhauser, G. [Vienna University of Technology-Atominstitut, Vienna (Austria)

    2011-07-01

    The TRIGA Mark II Vienna is one of the last TRIGA reactors utilizing a mixed core with High Enrich Uranium (HEU) fuel. Due to the US Fuel Return Program, the Vienna University of Technology/Atominstitut (ATI) is obliged to return its HEU fuel by 2019. There is no final decision on any further utilization of the Vienna research reactor beyond that point. However, of all possible scenarios of the future, the conversion of the current core into Low Enriched Uranium (LEU) fuel and the complete replacement of all existing 83 burned FE(s) by new fresh FE(s) are investigated herein. This paper presents detailed reactor design calculations for three different reactor cores. The core 1 employs 104-type, core 2 uses 108-type and core 3 is loaded with mixed TRIGA fuels (i.e. 104 and 108). The combination of the Monte Carlo based neutronics code MCNP5, Oak Ridge Isotope Generation and depletion code ORIGEN2 and diffusion theory based reactor physics program TRIGLAV is used for this study. On the basis of this neutronics study, the amount of fuel required for a possible future reactor operation and its cost minimization is presented in this paper. The criticality, core excess reactivity, length of initial life cycle and thermal flux density distribution is simulated for three different cores. Keeping the utilization of existing fourteen 104-type FE(s) (i.e. six burned and eight fresh FE(s)) in view, the core 3 is found the most economical, enduring and safe option for future of the TRIGA Mark II reactor in Vienna. (author)

  14. TRIGA MARK II first research reactor facility in Kingdom of Morocco

    The research reactor facility is located at Centre d'Etudes Nucleaires de la Maamora(CENM), located approximately 25 kilometers north of the city of Rabat. This facility will enable CNESTEN, as the operating organization, to fulfil its missions for promotion of nuclear technology in Morocco, contribute to the implementation of a national nuclear power program, and assist the state in monitoring nuclear activities for protection of the public and environment. The reactor building include TRIGA Mark II research reactor with an initial power level of 2000kW (t), and equipped for a planned future upgrade to 3,000-kilowatts.The facility is the keystone structure of CENM, and contain in addition to the TRIGA research reactor, extensively equipped laboratories and all associate support systems, structures, and supply facilities with the support of the AIEA, French CEA and LLNL (USA). The CENM with its TRIGA reactor and fully equipped laboratories will give the kingdom of Morocco its first nuclear installation with extensive capabilities. These will include the production of radioisotopes for medical, industrial and environmental uses, metallurgy and chemistry, implementation of nuclear analytical techniques such as neutron activation analysis and non-destructive examination techniques, as well as carrying out basic research programs in solid state and reactor physics. The feedback from the commissioning and the implementation of the safety standards during this phase was very interesting from safety point of view. The TRIGA Mark II research reactor at CENM achieved initial criticality on May 2, 2007 at 13:30 with 71 fuel elements and culminated with the successful completion of the full power endurance testing on 6 September, 2007.

  15. Optimization of a Potential New Core of the TRIGA Mark II Reactor Vienna

    The TRIGA Mark II Vienna is one of the last TRIGA reactors utilizing a mixed core with High Enrich Uranium (HEU) fuel. Due to the US Fuel Return Program, the Vienna University of Technology/Atominstitut (ATI) is obliged to return its HEU fuel by 2019. There is no final decision on any further utilization of the Vienna research reactor beyond that point. However, of all possible scenarios of the future, the conversion of the current core into Low Enriched Uranium (LEU) fuel and the complete replacement of all existing 83 burned FE(s) by new fresh FE(s) are investigated herein. This paper presents detailed reactor design calculations for three different reactor cores. The core 1 employs 104-type, core 2 uses 108-type and core 3 is loaded with mixed TRIGA fuels (i.e. 104 and 108). The combination of the Monte Carlo based neutronics code MCNP5, Oak Ridge Isotope Generation and depletion code ORIGEN2 and diffusion theory based reactor physics program TRIGLAV is used for this study. On the basis of this neutronics study, the amount of fuel required for a possible future reactor operation and its cost minimization is presented in this paper. The criticality, core excess reactivity, length of initial life cycle and thermal flux density distribution is simulated for three different cores. Keeping the utilization of existing fourteen 104-type FE(s) (i.e. six burned and eight fresh FE(s)) in view, the core 3 is found the most economical, enduring and safe option for future of the TRIGA Mark II reactor in Vienna. (author)

  16. Neutron flux characterisation of the Pavia TRIGA Mark II research reactor for radiobiological and microdosimetric applications.

    Alloni, D; Prata, M; Salvini, A; Ottolenghi, A

    2015-09-01

    Nowadays the Pavia TRIGA reactor is available for national and international collaboration in various research fields. The TRIGA Mark II nuclear research reactor of the Pavia University offers different in- and out-core neutron irradiation channels, each characterised by different neutron spectra. In the last two years a campaign of measurements and simulations has been performed in order to guarantee a better characterisation of these different fluxes and to meet the demands of irradiations that require precise information on these spectra in particular for radiobiological and microdosimetric studies. Experimental data on neutron fluxes have been collected analysing and measuring the gamma activity induced in thin target foils of different materials irradiated in different TRIGA experimental channels. The data on the induced gamma activities have been processed with the SAND II deconvolution code and finally compared with the spectra obtained with Monte Carlo simulations. The comparison between simulated and measured spectra showed a good agreement allowing a more precise characterisation of the neutron spectra and a validation of the adopted method. PMID:25958412

  17. Neutronic Analysis of the 3 MW TRIGA MARK II Research Reactor, Part I: Monte Carlo Simulation

    This study deals with the neutronic analysis of the current core configuration of a 3 MW TRIGA MARK II research reactor at Atomic Energy Research Establishment (AERE), Savar, Dhaka, Bangladesh and validation of the results by benchmarking with the experimental, operational and available Final Safety Analysis Report (FSAR) values. The three-dimensional continuous-energy Monte Carlo code MCNP4C was used to develop a versatile and accurate full-core model of the TRIGA core. The model represents in detail all components of the core with literally no physical approximation. All fresh fuel and control elements as well as the vicinity of the core were precisely described. Continuous energy cross-section data from ENDF/B-VI and S(α, β) scattering functions from the ENDF/B-V library were used. The validation of the model against benchmark experimental results is presented. The MCNP predictions and the experimentally determined values are found to be in very good agreement, which indicates that the Monte Carlo model is correctly simulating the TRIGA reactor. (author)

  18. Neutron flux characterisation of the Pavia Triga Mark II research reactor for radiobiological and microdosimetric applications

    Nowadays the Pavia TRIGA reactor is available for national and international collaboration in various research fields. The TRIGA Mark II nuclear research reactor of the Pavia University offers different in- and out-core neutron irradiation channels, each characterised by different neutron spectra. In the last two years a campaign of measurements and simulations has been performed in order to guarantee a better characterisation of these different fluxes and to meet the demands of irradiations that require precise information on these spectra in particular for radiobiological and microdosimetric studies. Experimental data on neutron fluxes have been collected analysing and measuring the gamma activity induced in thin target foils of different materials irradiated in different TRIGA experimental channels. The data on the induced gamma activities have been processed with the SAND II deconvolution code and finally compared with the spectra obtained with Monte Carlo simulations. The comparison between simulated and measured spectra showed a good agreement allowing a more precise characterisation of the neutron spectra and a validation of the adopted method. (authors)

  19. Follow-up the commissioning of CENM TRIGA Mark II research reactor on safety level

    The follow-up of the commissioning of the CENM-TRIGA Mark II Reactor has been performed in conformance with national regulation and the IAEA standards. For this purpose, the CNESTEN established a safety committee to review all safety aspects during reactor commissioning and operation. A set of hold points was established in the commissioning program, typically at the end of each stage to ensure that (i) test results have been reviewed by the safety committee and meet acceptance criterion, and (ii) requirements for the performance of the following stage of the commissioning program reviewed and understood by all the parties

  20. Fuel element burn-up calculation in ITU TRIGA Mark-II reactor

    The reactivity defect of fuel elements in ITU TRIGA Mark-II reactor core at 250 kW power have been calculated by considering the reactor operation history. A two-dimensional, four-group diffusion computer code TRIGLAV is used for the calculations. The unit-cell macroscopic cross sections and diffusion coefficients are generated with the WIMS-D/4 code. Two dimensional effects like vicinity of control rods, water gaps, dummy graphite elements, void channels are considered. The calculated reactivity worth of the fuel elements at known burn up are in agreement with experimental values of the fuel elements located in the reactor core without two dimensional effects. (author)

  1. Biological Tests for Boron Neutron Capture Therapy Research at the TRIGA Mark II Reactor in Pavia

    The thermal column of the TRIGA Mark II reactor of the Pavia University is used as an irradiation facility to perform biological tests and irradiations of living systems for Boron Neutron Capture Therapy (BNCT) research. The suitability of the facility has been ensured by studying the neutron flux and the photon background in the irradiation chamber inside the thermal column. This characterization has been realized both by flux and dose measurements as well as by Monte Carlo simulations. The routine irradiations concern in vitro cells cultures and different tumor animal models to test the efficacy of the BNCT treatment. Some results about these experiments will be described. (author)

  2. Time Evolution of Selected Actinides in TRIGA MARK-II Fuel

    Study is made on the evolution of several actinides capable of undergoing fission or breeding available on the Malaysian Nuclear Agency (MNA) TRIGA MARK-II fuel. Population distribution of burned fuel in the MNA reactor is determined with a model developed using WIMS. This model simulates fuel conditions in the hottest position in the reactor, thus the location where most of the burn up occurs. Theoretical basis of these nuclide time evolution are explored and compared with the population obtained from our models. Good agreements are found for the theoretical time evolution and the population of Uranium-235, Uranium-236, Uranium-238 and Plutonium-239. (author)

  3. Biological Tests for Boron Neutron Capture Therapy Research at the TRIGA Mark II Reactor in Pavia

    Protti, N.; Ballarini, F.; Bortolussi, S.; De Bari, A.; Stella, S.; Altieri, S. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); Nuclear Physics National Institute (INFN), Pavia (Italy); Bruschi, P. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); Bakeine, J.G.; Cansolino, L.; Clerici, A.M. [Laboratory of Experimental Surgery, Department of Surgery, University of Pavia, Pavia (Italy)

    2011-07-01

    The thermal column of the TRIGA Mark II reactor of the Pavia University is used as an irradiation facility to perform biological tests and irradiations of living systems for Boron Neutron Capture Therapy (BNCT) research. The suitability of the facility has been ensured by studying the neutron flux and the photon background in the irradiation chamber inside the thermal column. This characterization has been realized both by flux and dose measurements as well as by Monte Carlo simulations. The routine irradiations concern in vitro cells cultures and different tumor animal models to test the efficacy of the BNCT treatment. Some results about these experiments will be described. (author)

  4. Experimental and analytic investigation of the ITU TRIGA Mark-II reactor core

    Experimental and analytical studies have been performed to determine the temperature distribution as a function of reactor power in the TRIGA Mark-II reactor at the Istanbul Technical University (ITU). The lumped parameter model with four governing equations was used in the analytical model. Based on the mathematical model, a computer code has been developed for calculating fuel and coolant temperatures in the reactor core. The calculated results for fuel and coolant temperature in the reactor core for different reactor power levels have been compared with the experimental data. Agreements between experiment and results from the computer code are fairly good. (orig.)

  5. Operation experiences of the Kartini reactor using Bandung Triga Mark II spent fuels

    The operating history and improvements of the Kartini research reactor are presented. The Kartini reactor is operated during office hours: 5 days a week and 6-7 hours a day, except in particular cases. For 15 years since 1979 the Kartini reactor has been operated using spent fuels and used core from the Bandung Triga Mark II. Since 1994, however the Kartini reactor has been operated using the 104 SS type of fuel elements. Several difficulties and anomalies were encountered during its operation. A brief explanation of the maintenance, quality control and quality assurance programme during its operation are also discussed. (orig.)

  6. Mechanism design for the control rods conduction of TRIGA Mark III reactor in the NINR

    This work presents in the first chapter a general studio about the reactor and the importance of control rods in the reactor , the mechaniucal design attending to requisitions that are imposed for conditions of operation of the reactor are present in the second chapter, the narrow relation that exists with the new control console and the mechanism is developed in the thired chapter, this relation from a point of view of an assembly of components is presents in fourth chapter, finally reaches and perspectives of mechanism forming part of project of the automation of reactor TRIGA MARK III, are present in the fifth chapter. (Author)

  7. Immobilization of ion exchange radioactive resins of the TRIGA Mark III nuclear reactor

    This work has the objective to develop the process and to define the agglutinating material which allows the immobilization of the ion exchange radioactive resins coming from the TRIGA Mark III nuclear reactor contaminated with Ba-133, Co-60, Cs-137, Eu-152, and Mn-54 through the behavior analysis of different immobilization agents such as: bitumens, cement and polyester resin. According to the International Standardization the archetype samples were observed with the following tests: determination of free liquid, leaching, charge resistance, biodegradation, irradiation, thermal cycle, burned resistance. Generally all the tests were satisfactorily achieved, for each agent. Therefore, the polyester resin could be considered as the main immobilizing. (Author)

  8. Fuel burnup analysis of the TRIGA Mark II Reactor at the University of Pavia

    Chiesa, Davide; Clemenza, Massimiliano; Pozzi, Stefano; Previtali, Ezio; Sisti, Monica; Alloni, Daniele; Magrotti, Giovanni; Manera, Sergio; Prata, Michele; Salvini, Andrea; Cammi, Antonio; Zanetti, Matteo; Sartori, Alberto

    2015-01-01

    A time evolution model was developed to study fuel burnup for the TRIGA Mark II reactor at the University of Pavia. The results were used to predict the effects of a complete core reconfiguration and the accuracy of this prediction was tested experimentally. We used the Monte Carlo code MCNP5 to reproduce system neutronics in different operating conditions and to analyse neutron fluxes in the reactor core. The software that took care of time evolution, completely designed in-house, used the n...

  9. Investigations of cracks in the shielding concrete of a TRIGA Mark II reactor

    Cracks in the reactor shielding concrete of the TRIGA Mark II reactor, Vienna, caused an experimental and theoretical program to investigate the crack reason. After the investigation of the mechanical concrete data, the crack motion was measured as a function of various environmental temperatures. The temperature stress in the concrete was calculated analytically and with the finite-elements method and good accordance with the actual crack distribution was found. Finally some possibilities to avoid concrete cracks in future research reactor shielding construction are outlined. (orig.)

  10. Modification of the radial beam port of ITU TRIGA Mark II research reactor for BNCT applications.

    Akan, Zafer; Türkmen, Mehmet; Çakir, Tahir; Reyhancan, İskender A; Çolak, Üner; Okka, Muhittin; Kiziltaş, Sahip

    2015-05-01

    This paper aims to describe the modification of the radial beam port of ITU (İstanbul Technical University) TRIGA Mark II research reactor for BNCT applications. Radial beam port is modified with Polyethylene and Cerrobend collimators. Neutron flux values are measured by neutron activation analysis (Au-Cd foils). Experimental results are verified with Monte Carlo results. The results of neutron/photon spectrum, thermal/epithermal neutron flux, fast group photon fluence and change of the neutron fluxes with the beam port length are presented. PMID:25746919

  11. Collimator and shielding design for boron neutron capture therapy (BNCT) facility at TRIGA MARK II reactor

    The geometry of reactor core, thermal column, collimator and shielding system for BNCT application of TRIGA MARK II Reactor were simulated with MCNP5 code. Neutron particle lethargy and dose were calculated with MCNPX code. Neutron flux in a sample located at the end of collimator after normalized to measured value (Eid Mahmoud Eid Abdel Munem, 2007) at 1 MW power was 1.06 x 108 n/ cm2/ s. According to IAEA (2001) flux of 1.00 x 109 n/ cm2/ s requires three hours of treatment. Few modifications were needed to get higher flux. (Author)

  12. Epithermal neutron flux characterization of the TRIGA MARK II reactor, Ljubljana, Yugoslavia, for use in NAA

    The nonideality of the epithermal neutron flux distribution at a reactor site can be described by a 1/E1+α spectrum representation, with parameter α as a measure of nonideality. α-values were determined in 3 typical irradiation positions of the TRIGA MARK II reactor, Ljubljana, Yugoslavia, using the 'Cd-ratio for multi-monitor' method. The simpler 'Cd-ratio for dual monitor' method also yielded reliable results. This characterization is useful in the ko-method of NAA. (author) 18 refs.; 3 figs

  13. Neutron flux determination at the IPR-R1 Triga Mark I neutron beam extractor

    The IPR-R1 Triga Mark I Reactor located at the CDTN/CNEN, Belo Horizonte, Brazil, has been operating since November of 1960. In this work, measurements of thermal and epithermal neutron flux along the IPR-R1 neutron beam extractor were performed by neutron activation of reference materials using the two foils method. The obtained results were compared with results from two previous works: an experimental measurement done in a previous reactor core configuration and a numerical work made by Monte Carlo simulation using the actual reactor core configuration. The main purpose of this work is to update the measured data to the actual reactor core configuration. (author)

  14. Design and Implementation of a Fuzzy Controller for a TRIGA Mark III Reactor

    Rivero-Gutiérrez, Tonatiuh; Benítez-Read, Jorge S.; Segovia-De-los-Ríos, Armando; Longoria-Gándara, Luis C.; Palacios-Hernández, Javier C.

    2012-01-01

    The design and testing of a fuzzy rule based controller to regulate the power of a TRIGA Mark III research nuclear reactor are presented. The design does not require the current exact parameters of the point kinetic equations of the reactor. Instead, from a qualitative analysis of the actions taken by the operators during the reactor’s operation, a set of control rules is derived. The rules cover the operation of the reactor from low levels of about dozens of watts up to its full power level ...

  15. Radioactive waste management plan during the TRIGA Mark II and III decommissioning

    The decontamination and decommissioning (D and D) project of TRIGA Mark-I and Mark-II (KRR 1 and 2) was started in January 1997 and will be completed by December 2002. In the first year of the project, work was performed in preparation of the decommissioning plan, start of the environmental impact assessment and setup licensing procedure and documentation for the project with cooperation of the Korea Institute of Nuclear Safety (KINS). In the second year, Hyundai Engineering Company (HEC) with British Nuclear Fuels pie (BNFL) as technical assisting partner was designated as the contractor to do design and licensing documentation for the D and D of both reactors. After pre-design, a hazard and operability (HAZOP) study checked each step of the work. At the end of 1998, the decommissioning plan documentation including environmental impact assessment report was finished and submitted to the Ministry of Science and Technology (MOST) for licensing. It is expected to be issued by the end of September 1999. Practical work will then be started around the end of 1999. The safe treatment and management of the radioactive waste arising from the D and D activities is of utmost importance for successful completion of the practical dismantling work. This paper summarizes general aspects of radioactive waste treatment and management plan for the TRIGA Mark-I and II decommissioning work. (author)

  16. Treatment for dismantled radioactive solid waste from the TRIGA Mark-2 and 3

    Park, Seung Kook; Jung, Kyung Hwan

    1999-06-01

    Radioactive wastes are generally classified into 3 type depending on their physical property: liquid, solid and gaseous type. State-of -the art concerning liquid waste treatment has already been published; KAERI/TR-1315/99. Solid wastes classification package and treatment method will be studied to effectively manage them during the practical decommissioning work. All of the spent fuel produced during the operation of the TRIGA Mark-2 and 3 have been transported to the US last year, 1998, according to the spent fuel management strategy set-up by the US government for the non-proliferation of nuclear energy. Solid wastes are mainly all equipment existing inside of the reactors, activated concrete among the bio-shielded concrete, pipes, pimps, resin filter and it's housings, heat-exchangers, liquid waste storage tanks, to radioactive waste storage treatment facilities and so on. Solid wastes are generally low-level. They are classified according to the national regulation and nuclear law and IAEA Safety Standard Series ST-1(1996). Medium level radioactive wastes from reactor structures, mainly stainless steel component from the Rotary Specimen Rack(RSR) will be properly dismantled and stored in a shield container such as TIF(TRIGA Irradiated Fuel) container. While, low-level solid waste will be treated and packed in a ISO container(4m{sup 3} ISO container for example) according to the IAEA recommendation. And combustible solid waste such as cloths, gloves, paper etc. will be packed in a 200 liters drum. This state-of-the art shows a general feature of the solid radioactive waste management which will be produced during the decommissioning of the TRIGA Mark-2 and 3 research reactors. (author). 17 refs., 17 tabs., 2 figs.

  17. Neutronics analysis of the initial core of the TRIGA Mark II reactor

    Khan, R., E-mail: rustamzia@yahoo.co [Vienna University of Technology, Atominstitute (ATI), Stadion allee 2, A-1020, Vienna (Austria); Stummer, T.; Boeck, H.; Villa, M. [Vienna University of Technology, Atominstitute (ATI), Stadion allee 2, A-1020, Vienna (Austria)

    2011-05-15

    Highlights: The TRIGA Mark II Vienna is modeled employing MCNP5. The model is confirmed through three different experiments. Initial critical, reactivity distribution and flux mapping experiment. - Abstract: The Atominstitute (ATI) of Vienna University of Technology (VUT) operates a TRIGA Mark II research reactor since March 1962. Its initial criticality was achieved on 7th March 1962 when 57th Fuel Element (FE) was loaded to the core. This paper describes the development of the MCNP model of the TRIGA reactor and its validation through three different experiments i.e. initial criticality, reactivity distribution and a thermal flux mapping experiment in the reactor core. All these experiments were performed on the initial core configuration. The MCNP model includes all necessary core components i.e. FE, Graphite Element GE, neutron Source Element (SE), Central IRradiation channel (CIR) etc. Outside the core, this model simulates the annular grooved graphite reflector, the thermal and thermalizing column, four beam tubes and the reactor water tank up to 100 cm in radial and +60 and -60 cm in axial direction. Each grid position at its exact location is modeled. This model employs the ENDF/B-VI data library except for the Sm-isotopes which are taken from JEFF 3.1 because ENDF/B-VI lacks samarium (Sm) cross sections. For the first experiment, the model predicts an effective multiplication factor ({kappa}{sub eff}) of 1.00183 with an estimated standard deviation 0.00031 which is very close to the experimental value 1.00114. The second experiment measures the reactivity values of four FE and one GE. In comparison to the MCNP results, the percent difference ranges from 4 to 22. The third experiment verifies the model at a local level with the radial and axial thermal flux density distribution in the core. Though the trends are similar, the MCNP model overestimates the radial thermal flux density in the core and underestimates these results at the core periphery.

  18. Neutronics analysis of the initial core of the TRIGA Mark II reactor

    Highlights: → The TRIGA Mark II Vienna is modeled employing MCNP5. → The model is confirmed through three different experiments. → Initial critical, reactivity distribution and flux mapping experiment. - Abstract: The Atominstitute (ATI) of Vienna University of Technology (VUT) operates a TRIGA Mark II research reactor since March 1962. Its initial criticality was achieved on 7th March 1962 when 57th Fuel Element (FE) was loaded to the core. This paper describes the development of the MCNP model of the TRIGA reactor and its validation through three different experiments i.e. initial criticality, reactivity distribution and a thermal flux mapping experiment in the reactor core. All these experiments were performed on the initial core configuration. The MCNP model includes all necessary core components i.e. FE, Graphite Element GE, neutron Source Element (SE), Central IRradiation channel (CIR) etc. Outside the core, this model simulates the annular grooved graphite reflector, the thermal and thermalizing column, four beam tubes and the reactor water tank up to 100 cm in radial and +60 and -60 cm in axial direction. Each grid position at its exact location is modeled. This model employs the ENDF/B-VI data library except for the Sm-isotopes which are taken from JEFF 3.1 because ENDF/B-VI lacks samarium (Sm) cross sections. For the first experiment, the model predicts an effective multiplication factor (κeff) of 1.00183 with an estimated standard deviation 0.00031 which is very close to the experimental value 1.00114. The second experiment measures the reactivity values of four FE and one GE. In comparison to the MCNP results, the percent difference ranges from 4 to 22. The third experiment verifies the model at a local level with the radial and axial thermal flux density distribution in the core. Though the trends are similar, the MCNP model overestimates the radial thermal flux density in the core and underestimates these results at the core periphery.

  19. Monte Carlo Simulation of the TRIGA Mark II Benchmark Experiment with Burned Fuel

    Monte Carlo calculations of a criticality experiment with burned fuel on the TRIGA Mark II research reactor are presented. The main objective was to incorporate burned fuel composition calculated with the WIMSD4 deterministic code into the MCNP4B Monte Carlo code and compare the calculated keff with the measurements. The criticality experiment was performed in 1998 at the ''Jozef Stefan'' Institute TRIGA Mark II reactor in Ljubljana, Slovenia, with the same fuel elements and loading pattern as in the TRIGA criticality benchmark experiment with fresh fuel performed in 1991. The only difference was that in 1998, the fuel elements had on average burnup of ∼3%, corresponding to 1.3-MWd energy produced in the core in the period between 1991 and 1998. The fuel element burnup accumulated during 1991-1998 was calculated with the TRIGLAV in-house-developed fuel management two-dimensional multigroup diffusion code. The burned fuel isotopic composition was calculated with the WIMSD4 code and compared to the ORIGEN2 calculations. Extensive comparison of burned fuel material composition was performed for both codes for burnups up to 20% burned 235U, and the differences were evaluated in terms of reactivity. The WIMSD4 and ORIGEN2 results agreed well for all isotopes important in reactivity calculations, giving increased confidence in the WIMSD4 calculation of the burned fuel material composition. The keff calculated with the combined WIMSD4 and MCNP4B calculations showed good agreement with the experimental values. This shows that linking of WIMSD4 with MCNP4B for criticality calculations with burned fuel is feasible and gives reliable results

  20. Neutronics analysis of the current core of the TRIGA Mark II reactor Vienna

    This paper presents the part of PhD work performed at the TRIGA Mark II Vienna. A detailed three dimensional MCNP model of the reactor was developed. The neutronics library JEFF3.1 was applied to this model. The model was completed by employing the fresh fuel composition experiments and was confirmed by the initial criticality, reactivity distribution and thermal flux distribution performed in 1962. To analyse the current burned core, burn up and its relevant material composition was calculated by ORIGEN2 and confirmed by gamma spectroscopy of six spent Fuel Elements FE(s). This new material composition of the current core was incorporated into the already developed MCNP model. This paper presents the current core calculations employing MCNP5 and its experimental validation through criticality and reactivity distribution experiments, performed at the TRIGA Mark II research reactor Vienna. The MCNP predicts the criticality of the current core on loading of 78th FE in the core which is also confirmed experimentally. Five FE(s) were calculated and measured for their reactivity worths. The deviations between theoretical results and experimental observations were in range from 3% to 17%. (author)

  1. Criticality calculation in TRIGA MARK II PUSPATI Reactor using Monte Carlo code

    A Monte Carlo simulation of the Malaysian nuclear reactor has been performed using MCNP Version 5 code. The purpose of the work is the determination of the multiplication factor (keff) for the TRIGA Mark II research reactor in Malaysia based on Monte Carlo method. This work has been performed to calculate the value of keff for two cases, which are the control rod either fully withdrawn or fully inserted to construct a complete model of the TRIGA Mark II PUSPATI Reactor (RTP). The RTP core was modeled as close as possible to the real core and the results of keff from MCNP5 were obtained when the control fuel rods were fully inserted, the keff value indicates the RTP reactor was in the subcritical condition with a value of 0.98370±0.00054. When the control fuel rods were fully withdrawn the value of keff value indicates the RTP reactor is in the supercritical condition, that is 1.10773±0.00083. (Author)

  2. In-situ gamma spectrometry measurements of time-dependent Xenon-135 inventory in the TRIGA Mark II reactor Vienna

    Riede, Julia; Boeck, Helmuth

    2013-01-01

    In this work, it has been shown that the time dependent Xe-135 inventory in the TRIGA Mark II reactor in Vienna, Austria can be measured via gamma spectrometry even in the presence of strong background radiation. It is focussing on the measurement of (but not limited to) the nuclide Xe-135. The time dependent Xe-135 inventory of the TRIGA Mark II reactor Vienna has been measured using a temporary beam line between one fuel element of the core placed onto the thermal column after shutdown and ...

  3. Investigation of subcritical multiplication parameters in TRIGA Mark II accelerator driven system

    Highlights: • TRIGA ADS neutron external source was numerically investigated. • Source target material, radius, position, and incident beam energy were studied. • Maximum neutron yield for W, Pb, and W–Cu targets are at radii 3.25, 3.5 and 7 cm. • Maximum source efficiency for targets at the given core is achieved at the center. • Maximum source efficiency is achieved at 40 MeV incident electron beam energy. - Abstract: The accelerator driven system (ADS) is a very interesting option to improve the safety of nuclear power reactor and for transmutation of spent fuel. The Texas phase of the reactor–accelerator coupling experiment (RACE), completed in March 2006, demonstrated the feasibility of operating a training research isotopes general atomic (TRIGA) research reactor in a subcritical configuration driven to a significant power by an electron LINAC neutron source (photoneutron). In the present study, the effects of changing the source cylindrical target material, radius, position and the electron beam energy on the final neutron production, fission probability, and the subcritical system multiplication of TRIGA Mark II research reactor, have been numerically investigated. Three target materials are used: Tungsten, Lead and Tungsten–Copper alloy, while varying the target radius from 2 to 8 cm, the source position at three locations, and the beam energy from 10 to 55 MeV. The investigation is based on the numerical calculation of the subcritical multiplication factor and the external source efficiency using Monte Carlo MCNPX code. Through the comparison of the studied cases results, the favorable target material and radius, source position, and beam energy can be obtained

  4. Immobilization of Ion Exchange radioactive resins of the TRIGA Mark III Nuclear Reactor; Inmovilizacion de resinas de intercambio ionico radiactivas del reactor nuclear TRIGA Mark III

    Garcia Martinez, H

    1999-07-01

    In the last decades many countries in the world have taken interest in the use, availability, and final disposal of dangerous wastes in the environment, within these, those dangerous wastes that contain radioactive material. That is why studies have been made on materials used as immobilization agent of radioactive waste that may guarantee its storage for long periods of time under drastic conditions of humidity, temperature change and biodegradation. In mexico, the development of different applications of radioactive material in the industry, medicine and investigation, have generated radioactive waste, sealed and open sources, whose require a special technological development for its management and final disposal. The present work has as a finality to develop the process and define the agglutinating material, bitumen, cement and polyester resin that permits immobilization of resins of Ionic Exchange contaminated by Barium 153, Cesium 137, Europium 152, Cobalt 60 and Manganese 54 generated from the nuclear reactor TRIGA Mark III. Ionic interchange contaminated resin must be immobilized and is analysed under different established tests by the Mexican Official Standard NOM-019-NUCL-1995 {sup L}ow level radioactive wastes package requirements for its near-surface final disposal. Immobilization of ionic interchange contaminated resins must count with the International Standards applicable in this process; in these standards, the following test must be taken in prototype examples: Free-standing water, leachability, compressive strength, biodegradation, radiation stability, thermal stability and burning rate. (Author)

  5. Activation calculation of steel of the control rods of TRIGA Mark III reactor; Calculo de activacion del acero de las barras de control del reactor TRIGA Mark III

    Garcia M, T.; Cruz G, H. S.; Ruiz C, M. A.; Angeles C, A., E-mail: teodoro.garcia@inin.gob.mx [ININ, Carretera Mexico-Toluca sn, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    In the pool of TRIGA Mark III reactor of the Instituto Nacional de Investigaciones Nucleares (ININ), there are control rods that were removed from the core, and which are currently on shelves of decay. These rods were part of the reactor core when only had fuel standard (from 1968-1989). To conduct a proper activation analysis of the rods, is very important to have well-characterized the materials which are built, elemental composition of the same ones, the atomic densities and weight fractions of the elements that constitute them. To determine the neutron activation of the control rods MCNP5 code was used, this code allows us to have well characterized the radionuclides inventory that were formed during irradiation of the control rods. This work is limited to determining the activation of the steel that is part of the shielding of the control rods, the nuclear fuel that is in the fuel follower does not include. The calculation model of the code will be validated with experimental measurements and calculating the activity of fission products of the fuel follower which will take place at the end of 2014. (Author)

  6. Renewal and upgrading of the TRIGA Mark II research reactor in Ljubljana

    At the 250 kW TRIGA Mark II research reactor in Ljubljana, ever since the beginning of operation in 1966, gradual modification and modernization have been taking place. In 1991 the reactor has been almost completely reconstructed and upgraded. The reconstruction consisted mainly of replacing the grid plates, the control rod mechanisms and the control unit. A new PC based system to collect the operational radiation data of the reactor was developed. A new spent fuel storage facility was built in the basement of the reactor building with a capacity of 630 spent fuel elements. The main novelty in the reactor physics and operational features of the reactor was installation of the pulse rod. The following experiments were conducted: initial criticality, excess reactivity measurement, control rod worth measurement, fuel temperature distribution, fuel temperature reactivity coefficient, pulse parameter measurements (peak power, prompt energy, peak temperature). Flux distributions in steady state and pulse mode were measured as well. The experiments were performed with completely fresh fuel of 12 w% Standard Stainless Steel type. The core configuration was uniform (one fuel element type, including fuelled followers) and compact (no irradiation channels or gaps), as such an array is particularly convenient for testing computer codes for TRIGA reactor calculations

  7. Gamma spectrometry inspection of TRIGA MARK II fuel using caesium isotopes

    Karimzadeh, S., E-mail: sam.karimzadeh@ati.ac.a [Vienna University of Technology, Institute of Atomic and Subatomic Physics (ATI), Stadionallee 2, A-1020 Vienna (Austria); Khan, R.; Boeck, H. [Vienna University of Technology, Institute of Atomic and Subatomic Physics (ATI), Stadionallee 2, A-1020 Vienna (Austria)

    2011-01-15

    Research highlights: Cs isotopes are the best choices for the burn up determination of spent fuel. Gamma spectrometer calibration using MCNP5. Cs-ratio can be applied by relative calibration method. - Abstract: Gamma spectrometry is one of the common methods to inspect the spent fuel from research reactors. This method has been applied to in-pool measurements of the Spent Fuel Elements (SPEs) of the TRIGA Mark II research reactor. Due to mixed nature of the reactor core and complicated irradiation history of the fuel elements (FEs), the gamma spectrometry of the FE establishes improvements in the calculation and measurement of the SPE. In order to inspect the TRIGA SPE from dry storage and cooled fuel from the reactor pool, the selected spend fuels are scanned and measured using the fuel-scanning machine. Gamma spectrometry is performed by HPGe detector for spend fuel inspection and determination of the {sup 137}Cs activity and {sup 134}Cs/{sup 137}Cs ratio. In this work, the steps of the detector calibration and the use of the Monte Carlo radiation transport code (MCNP5) have been described. In addition, the fuel-scanning machine and the gamma spectrometer are modelled by MCNP5 to simulate the gamma transport from fuel to detector. It also simulate the gamma spectrometer calibration for the burn up determination of the spend fuel. The results from MCNP5 simulation are applied to spectroscopic measurements and compared with the theoretical predictions of the neutronics code ORIGEN2 in this research work.

  8. Development of neutron beam projects at the University of Texas TRIGA Mark II Reactor

    Recently, the UT-TRIGA research reactor was licensed and has become fully operational. This reactor, the first new US university reactor in 17 years, is the focus of a new reactor laboratory facility which is located on the Balcones Research Center at The University of Texas at Austin. The TRIGA Mark II reactor is licensed for 1.1 MW steady power operation, 3 dollar pulsing, and includes five beam ports. Various neutron beam-line projects have been assigned to each beam port. Neutron Depth Profiling (NDP) and the Texas Cold Neutron Source (TCNS) are close to completion and will be operational in the near future. The design of the NDP instrument has been completed, a target chamber has been built, and the thermal neutron collimator, detectors, data acquisition electronics, and data processing computers have been acquired. The target chamber accommodates wafers up to 12'' in diameter and provides remote positioning of these wafers. The design and construction of the TCNS has been completed. The TCNS consists of a moderator (mesitylene), a neon heat pipe, a cryogenic refrigerator, and neutron guide tubes. In addition, fission-fragment research (HIAWATHA), Neutron Capture Therapy, and Neutron Radiography are being pursued as projects for the other three beam ports. (author)

  9. Numerical simulation of non-steady state neutron kinetics of the TRIGA Mark II reactor Vienna

    Riede, J., E-mail: jriede@ati.ac.at; Boeck, H., E-mail: boeck@ati.ac.at

    2013-12-15

    Highlights: • Power changes after reactivity changes have been measured with high time resolution. • Time dependent power changes after reactivity changes have been calculated numerically including feedback mechanisms. • The model has been verified by comparing numerical results to experimental data. • The verified model has been used to predict time dependent power changes after several reactivity changes. - Abstract: This paper presents an algorithm for numerical simulations of non-steady states of the TRIGA Mark II reactor in Vienna, Austria. The primary focus of this work has been the development of an algorithm which provides time series of integral neutron flux after reactivity changes introduced by perturbations without the usage of thermal-hydraulic/neutronic numerical code systems for the TRIGA reactor in Vienna, Austria. The algorithm presented takes into account both external reactivity changes as well as internal reactivity changes caused by feedback mechanisms like effects caused by temperature changes of the fuel and poisoning effects. The resulting time series have been compared to experimental results.

  10. Numerical simulation of non-steady state neutron kinetics of the TRIGA Mark II reactor Vienna

    Highlights: • Power changes after reactivity changes have been measured with high time resolution. • Time dependent power changes after reactivity changes have been calculated numerically including feedback mechanisms. • The model has been verified by comparing numerical results to experimental data. • The verified model has been used to predict time dependent power changes after several reactivity changes. - Abstract: This paper presents an algorithm for numerical simulations of non-steady states of the TRIGA Mark II reactor in Vienna, Austria. The primary focus of this work has been the development of an algorithm which provides time series of integral neutron flux after reactivity changes introduced by perturbations without the usage of thermal-hydraulic/neutronic numerical code systems for the TRIGA reactor in Vienna, Austria. The algorithm presented takes into account both external reactivity changes as well as internal reactivity changes caused by feedback mechanisms like effects caused by temperature changes of the fuel and poisoning effects. The resulting time series have been compared to experimental results

  11. Simulation of TRIGA Mark II Benchmark Experiment using WIMSD4 and CITATION codes

    This paper presents a simulation of the TRIGA Mark II Benchmark Experiment, Part I: Steady-State Operation and is part of the calculation methodology validation developed to the neutronic calculation of the CDTN's TRIGA IPR - R1 reactor. A version of the WIMSD4, obtained in the Centro de Tecnologia Nuclear, in Cuba, was used in the cells calculation. In the core calculations was adopted the diffusion code CITATION. Was adopted a 3D representation of the core and the calculations were carried out at two energy groups. Many of the experiments were simulated, including, Keff, control rods reactivity worth, fuel elements reactivity worth distribution and the fuel temperature reactivity coefficient. The comparison of the obtained results, with the experimental results, shows differences in the range of the accuracy of the measurements, to the control rods worth and fuel temperature reactivity coefficient, or on an acceptable range, following the literature, to the Keff and fuel elements reactivity worth distribution and the fuel temperature reactivity coefficient. The comparison of the obtained results, with the experimental. results, shows differences in the range of the accuracy of the measurements, to the control rods worth and fuel temperature reactivity coefficient, or in an acceptable range, following the literature, to the Keff and fuel elements reactivity worth distribution. (author)

  12. Gamma spectrometry inspection of TRIGA MARK II fuel using caesium isotopes

    Research highlights: → Cs isotopes are the best choices for the burn up determination of spent fuel. → Gamma spectrometer calibration using MCNP5. → Cs-ratio can be applied by relative calibration method. - Abstract: Gamma spectrometry is one of the common methods to inspect the spent fuel from research reactors. This method has been applied to in-pool measurements of the Spent Fuel Elements (SPEs) of the TRIGA Mark II research reactor. Due to mixed nature of the reactor core and complicated irradiation history of the fuel elements (FEs), the gamma spectrometry of the FE establishes improvements in the calculation and measurement of the SPE. In order to inspect the TRIGA SPE from dry storage and cooled fuel from the reactor pool, the selected spend fuels are scanned and measured using the fuel-scanning machine. Gamma spectrometry is performed by HPGe detector for spend fuel inspection and determination of the 137Cs activity and 134Cs/137Cs ratio. In this work, the steps of the detector calibration and the use of the Monte Carlo radiation transport code (MCNP5) have been described. In addition, the fuel-scanning machine and the gamma spectrometer are modelled by MCNP5 to simulate the gamma transport from fuel to detector. It also simulate the gamma spectrometer calibration for the burn up determination of the spend fuel. The results from MCNP5 simulation are applied to spectroscopic measurements and compared with the theoretical predictions of the neutronics code ORIGEN2 in this research work.

  13. Determination of the thermal-hydraulic parameters of ITU TRIGA Mark-II reactor

    In this study, a transient, one-dimensional thermal-hydraulic subchannel analysis for I.T.U. TRIGA Mark-II reactor was employed. Mixed convection is considered in modelling to enhance the capability of the computer code. After the continuity, conservation of energy, momentum balance equations for coolant in axial direction and the heat-conduction equation for the fuel rod in radial direction had been written, they were discretized by using the control volume approach to obtain a set of algebraic equations. By the aid of the discretized continuity and momentum balance equations, a pressure and a pressure-correction equations were derived. Then, two different FORTRAN programs called TRIGATH (TRIGA Thermal-Hydraulics) and TRIGATH-R (TRIGATH Revised) have been developed to solve this set of algebraic equations by using SIMPLE and SIMPLER algorithms respectively. As a result, the temperature distributions of the coolant and the fuel rods as well as the velocity and pressure distributions of the coolant have been estimated for both transient and steady state regimes from both algorithms. Their results, which are in good agreement, are compared to the results of the computer code

  14. Relative fission product yield determination in the USGS TRIGA Mark I reactor

    Koehl, Michael A.

    Fission product yield data sets are one of the most important and fundamental compilations of basic information in the nuclear industry. This data has a wide range of applications which include nuclear fuel burnup and nonproliferation safeguards. Relative fission yields constitute a major fraction of the reported yield data and reduce the number of required absolute measurements. Radiochemical separations of fission products reduce interferences, facilitate the measurement of low level radionuclides, and are instrumental in the analysis of low-yielding symmetrical fission products. It is especially useful in the measurement of the valley nuclides and those on the extreme wings of the mass yield curve, including lanthanides, where absolute yields have high errors. This overall project was conducted in three stages: characterization of the neutron flux in irradiation positions within the U.S. Geological Survey TRIGA Mark I Reactor (GSTR), determining the mass attenuation coefficients of precipitates used in radiochemical separations, and measuring the relative fission products in the GSTR. Using the Westcott convention, the Westcott flux, modified spectral index, neutron temperature, and gold-based cadmium ratios were determined for various sampling positions in the USGS TRIGA Mark I reactor. The differential neutron energy spectrum measurement was obtained using the computer iterative code SAND-II-SNL. The mass attenuation coefficients for molecular precipitates were determined through experiment and compared to results using the EGS5 Monte Carlo computer code. Difficulties associated with sufficient production of fission product isotopes in research reactors limits the ability to complete a direct, experimental assessment of mass attenuation coefficients for these isotopes. Experimental attenuation coefficients of radioisotopes produced through neutron activation agree well with the EGS5 calculated results. This suggests mass attenuation coefficients of molecular

  15. Determination of the neutron fluxes in the research nuclear reactors: the Triga Mark I and the WRS

    In this paper is presented the determination of the thermal, epithermal and fast neutron fluxes, using neutron activation analysis technique, for two research nuclear reactors of different design: the TRIGA Mark I reactor was designed by Gulf General Atomic Co in US and the W WRS reactor was designed in the URSS, both in the 50's years. (Author)

  16. Operation, maintenance, and utilization of 250 kW TRIGA Mark II reactor at the Institute Jozef Stefan, Ljubljana (Yugoslavia))

    At the Institute 'Jozef Stefan' in Ljubljana 250 kW TRIGA Mark II Reactor has been in operation since May 31, 1966. It is the steady state operated reactor without pulsing capabilities. In the paper the operational data, maintenance and utilization of the reactor are summarized for the first four years of reactor operation. (author)

  17. Characterization of the TRIGA Mark III reactor for k0 neutron activation analysis

    The k0 standardization for instrumental neutron activation analysis is a relatively new nuclear analytical technique. It is extended i n more than 20 countries of the world with reactor facilities, including some from Latin America. The great advantages of this technique (low uncertainties, fast and massive analysis, no standard necessity) with respect to relative, absolute and radiochemical activation analysis, are the reason of it fast introduction in Geology, Medicine, Agriculture and other fields of applications. But for the k0 instrumental neutron activation analysis implementation, the good knowledge of some reactor neutron flux and isotopes characteristics is necessary. The non ideality of the epithermal neutron flux temperature (Tn) and the k0 factors for more than 20 isotopes were determinate in the 3 typical irradiation positions of the TRIGA Mark III reactor of the National Nuclear Research Institute, Salazar, Mexico, using different experimental methods with conventional and non-conventional monitors

  18. Main configurations of the reactor core TRIGA Mark III of the ININ, during their operation

    The Reactor TRIGA Mark III is 43 years old since was put lay critical on November 8 of 1968 for the first time, along their operative life there have been 18 different configurations of the core, being three those more important: the first configuration with elements standard with an enrichment lightly minor than 20% in U-235, the second configuration that deserves out attention is when a mixed core was charged, composite of two different fuels as for their enrichment, the core consisted of 26 fuel elements Flip (of high enrichment approximately of 70%) more 3 control bars with follower of fuel Flip and 59 standard fuel elements, as those mentioned previously, finally is necessary to consider the recent reload of the reactor, with a compound core by fuel elements of low enrichment LEU 30/20. In this work the characteristics more important of the reactor are presented as well as of each one of the described cores. (Author)

  19. Neutron spectra in two beam ports of a TRIGA Mark III reactor with HEU fuel

    Before to change the HEU for Leu fuel of the ININ's TRIGA Mark III nuclear reactor the neutron spectra were measured in two beam ports using 5 and 10 W. Measurements were carried out in a tangential and a radial beam port using a Bonner sphere spectrometer. It was found that neutron spectra are different in the beam ports, in radial beam port the amplitude of thermal and fast neutrons are approximately the same while, in the tangential beam port thermal neutron peak is dominant. In the radial beam port the fluence-to-ambient dose equivalent factors are 131±11 and 124±10 p Sv-cm2 for 5 and 10 W respectively while in the tangential beam port the fluence-to-ambient dose equivalent factor is 55±4 p Sv-cm2 for 10 W. (Author)

  20. Enhancement of mechanical properties of blended polyethylene radiation capsules for the TRIGA MARK II Research Reactor

    Mechanical properties of blended polyethylene (PE) containing the antioxidant Irganox 1010 and the UV-absorber Tinuvin 326 were studied for future use as radiation capsule material for the TRIGA Mark II research reactor. High density and low density polyethylene were blended with the additives and tested for elongation at break, impact strength and gel content, before and after irradiation inside the nuclear reactor. Characterization via FTIR as well as determination of crystallization and melt transition temperatures through DSC were also conducted. It was found that the addition of the antioxidant at different amounts (from 0 to 4 phr) had various effects on the properties of the blended PE, with 0 phr being the amount at which there was the biggest increase in elongation at break and impact strength, post-irradiation. (author)

  1. Experimental measurement of the refrigerant temperature of the TRIGA Mark III reactor of the ININ

    With the object of knowing the axial temperature profile of the refrigerant in the core of the TRIGA Mark III reactor of the ININ, the temperatures of this, at the enter, in the center and the exit of the core were measured, in the positions: west 2, north 2 and south 1. This was made by means of the thermo pars introduction mounted in aluminum guides, connected to a measurer of digital temperature, whose resolution is of ± 0.1 C. The measurements showed a bigger heating of the refrigerant in the superior half of the core, that which suggests that the axial profile of temperature of the reactor is not symmetrical with respect to the center or that those temperature measurements in the center are not correct. (Author)

  2. Non-destructive material investigation with thermal neutrons at the TRIGA Mark II reactor in Vienna

    Neutron tomography providing 3D information about interior of an object is a very efficient tool to visualize inner defects of the materials, non-destructively. In this study, some applications of neutron tomography in different fields such as geology, aerospace, civil engineering and archaeology were presented. Distribution of minerals in pumice and rock samples, visualization of inner defects within a new developed titan aluminum turbine blade, and distribution of silica gel as an important impregnating agent in construction and restoration of buildings were investigated. The measurements of tomography projections taken in the 0 to 180o angle were performed with a thermal neutron flux of 105 at the TRIGA Mark II research reactor in Vienna, and the common filtered back projection method was used for the 3D image reconstruction. (author)

  3. Calculation of neutron fluxes in biological shield of the TRIGA Mark II reactor

    The complete calculation of neutron fluxes in biological shield and verification with experimental results is presented. Calculated results are obtained with TORT code (TORT-Three Dimensional Oak Ridge Discrete Ordinates Neutron/Photon Transport Code). Experimental results used for comparison are available from irradiation experiment with selected type of concrete and other materials in irradiation channel 4 in TRIGA Mark II reactor. These experimental results were used as a benchmark. Homogeneous type of problem (without inserted irradiation channel) and problem with asymmetry (inserted beam port 4, filled with different materials) were of interest for neutron flux calculation. Deviation from material data set up as original parameters is also considered (first of all presence of water in concrete and density of concrete) for type of concrete in biological shield and for selected type of concrete in irradiation channel. BUGLE-96 (47 neutron energy groups) library is used. Excellent agreement between calculated and experimental results for reaction rate is received.(author)

  4. Development process of the new control console of ININ's TRIGA mark III reactor

    A description of the development of the new ININ's TRIGA Mark III reactor control console is presented in this meeting. Most of the operation and safety monitoring of the reactor is carried out by means of a personal computer (PC), some interface cards, and an auxiliary computer that drives the control rod mechanisms. In this console, the safety actions are taken by the Protection System (SEC), which acquires the data directly from the safety related systems, specified in the reactor's console design technical specifications. The console, based on the concept of virtual instrumentation, is composed of a group of systems that make easier to the operator the activation of the sequential steps required to operate the reactor. (authors)

  5. Detection of a leaking boron-carbide control rod in a TRIGA Mark I reactor

    During a routine quarterly inspection of the boron-carbide control rods of the Omaha Veterans Administration Hospital 18 kW Triga Mark I reactor, a pin hole leak was detected approximately 3 mm from the chamfered edge. The leak was found by observing bubbles when the rod was withdrawn from the reactor tank for visual observation, and could not be seen with the naked eye. This suggests that pin hole leaks could occur and not be visually detected in control rods and fuel elements examined underwater. A review of the rod calibrations showed that the leak had not caused a loss in rod worth. Slides will be presented showing the bubbles observed during the inspection, together with an unmagnified and magnified view of the pin hole. (author)

  6. Present Services at the TRIGA Mark II Reactor of the JSI

    The TRIGA Mark II research reactor of the Jožef Stefan Institute has been continuously operating since the year 1966. The currently offered services include: (1) Neutron activation analysis in both instrumental and radiochemical modes; (2) neutron irradiation of various kinds of materials intended to be used for research and applicative purposes; (3) training and education of university students as well as on-job training of staff working in public and private institutions, (4) verification of computer codes and nuclear data, comprising primarily criticality calculations and neutron flux distribution studies and (5) testing and development of a digital reactivity meter. The paper briefly describes the aforementioned activities and shows that even such small reactors are still indispensable in nuclear science and technology. (author)

  7. Operating experience and maintenance at the TRIGA Mark II LENA reactor

    Reactor operation at the Triga Mark II LENA plant, at the University of Pavia, in the past two years has been greatly affected by fulfilment of the new Italian fire prevention act's requirements, by the final red-tape work to get the renewal of the operation licence and by answering to the observations of Inspectors of the Italian Ministry of Labour and Social Security. All personnel was involved in the revision of manuals and prescriptions according to government rules and new ideas on modern nuclear safety. Consequently reactor operation was largely reduced due to works going on in the plant and to the lack of practicability of the Radiochemistry Laboratory. Finally, at the end of May 1990, the Reactor Operation Licence was renewed for the time period 1990-1995 by the Italian Ministry of Industry. (orig.)

  8. Characterization of the neutron flux gradients in typical irradiation channels of a TRIGA Mark II reactor

    The neutron distribution in a defined volume (gradient) for different matrices (air, water, cellulose, biological material and silicon dioxide) in two typical irradiation channels (pneumatic tube (PT) and IC40-channel in the carousel facility) in the TRIGA Mark II reactor at the Jozef Stefan Institute (IJS) was studied. Experiment was based on inserting Fe wires (flux monitors) into the chosen matrices. The wires were cut into small pieces after irradiation and the induced activities of 59Fe measured. The results showed that for the studied geometry the average spatial thermal neutron flux inhomogeneities (for five studied matrices) are about 2.3% in the PT-channel and about 2.9% in the IC40-channel. (author)

  9. Thermal hydraulic parameter studies of heat exchanger for the TRIGA MARK II research reactor

    Thermal Hydraulic studies have being conducted at PUSPATI TRIGA Mark II (RTP) Nuclear Research Reactor. The purpose of this study is to determine the heat transfer characteristic and heat exchanger performance at difference reactor power. Fundamental concept and a plate type application of heat exchanger in RTP are presented in this study. A plate type heat exchanger is a device for RTP reactor cooling system built for efficient heat transfer from one fluid to another. The study involves the observation of inlet and outlet temperature profile, flow rate and pressure at the reactor pool and heat exchanger. The observed parameters are compared to basic engineering calculation and the output of the study has been beneficial to evaluate the performance of newly-installed plate type heat exchanger. (author)

  10. TRIGASIM: A computer program to simulate a TRIGA Mark I Reactor

    A Fortran-77 computer program has been written which simulates the operation of a TRIGA Mark I Reactor. The 'operator' has options at 1-second intervals, of raising rods, lowering rods, maintaining rods steady, dropping a rod, or scramming the reactor. Results are printed to the screen, and to 2 output files - a tabular record and a logarithmic plot of the power. The Point Kinetic Equations are programmed with 6 delayed groups, quasi-static power feedback, and forward differencing. A pulsing option is available, with simulation which employs the Fuchs Model. A pulse-tail model has been devised to simulate behavior for a few minutes following a pulse. Both graphic and tabular output are also available for the pulses. (author)

  11. Development process of the new control console of ININ's TRIGA mark III reactor

    Rivero-Gutierrez, T. [Inst. Nacional de Investigationes Nucleares ININ, Gerencia de Ciencias Aplicadas, Carretera Mexico-Toluca S/N, Estado de Mexico, C.P. 52750 (Mexico); Inst. Tecnologico de Toluca, Div. de Estudios de Postgrado e Investigacion, Av. Tecnologico S/N, Estado de Mexico, C.P. 52140 (Mexico); Sainz-Mejia, E. [Inst. Nacional de Investigationes Nucleares ININ, Gerencia de Ciencias Aplicadas, Carretera Mexico-Toluca S/N, Estado de Mexico, C.P. 52750 (Mexico); Benitez-Read, J. S. [Inst. Nacional de Investigationes Nucleares ININ, Gerencia de Ciencias Aplicadas, Carretera Mexico-Toluca S/N, Estado de Mexico, C.P. 52750 (Mexico); Inst. Tecnologico de Toluca, Div. de Estudios de Postgrado e Investigacion, Av. Tecnologico S/N, Estado de Mexico, C.P. 52140 (Mexico); Marroquin, J. L. G. [Inst. Nacional de Investigationes Nucleares ININ, Gerencia de Ciencias Aplicadas, Carretera Mexico-Toluca S/N, Estado de Mexico, C.P. 52750 (Mexico)

    2006-07-01

    A description of the development of the new ININ's TRIGA Mark III reactor control console is presented in this meeting. Most of the operation and safety monitoring of the reactor is carried out by means of a personal computer (PC), some interface cards, and an auxiliary computer that drives the control rod mechanisms. In this console, the safety actions are taken by the Protection System (SEC), which acquires the data directly from the safety related systems, specified in the reactor's console design technical specifications. The console, based on the concept of virtual instrumentation, is composed of a group of systems that make easier to the operator the activation of the sequential steps required to operate the reactor. (authors)

  12. Microfungal Activity Test Of The Triga Mark II Reactor Tank Isolation to Aluminium corrosion

    In our pres ious study some pure species of micro fungal have been isolated from cooling water and samples taken from surrounding tank wall of TRIGA Mark II Reaktor. This study was conducted to determine their activities to aluminium 6061-T using modified method of Hortative (1962) in the speed of corrosion transmission process. Each isolate was inoculated into mineral nutrient solution. Changes of ph and reduced weight of Aluminium specimen weight between the experimental and the control groups, and the amounts were proportional to to the length of investigation times. The highest degree of the corrosion speed is given by Penicillium simplicissimum inoculant 2,95.10-6, followed by Paecilomyceus carneus 2,61.106, Penicillium canescens 2,59.10-6 and the control 2,11.106 respectively

  13. Design and Implementation of a Fuzzy Controller for a TRIGA Mark III Reactor

    Tonatiuh Rivero-Gutiérrez

    2012-01-01

    Full Text Available The design and testing of a fuzzy rule based controller to regulate the power of a TRIGA Mark III research nuclear reactor are presented. The design does not require the current exact parameters of the point kinetic equations of the reactor. Instead, from a qualitative analysis of the actions taken by the operators during the reactor’s operation, a set of control rules is derived. The rules cover the operation of the reactor from low levels of about dozens of watts up to its full power level of one megawatt. The controller is able to increase power from different initial values to a wide range of desired levels, maintaining constant levels for long periods of time. The controller’s output is the external reactivity, which is further converted to a control rod incremental movement. The fuzzy controller is implemented on the reactor’s digital operating console, and the results of a series of experiments are discussed.

  14. Neutron spectra at two beam ports of a TRIGA Mark III reactor loaded with HEU fuel.

    Vega-Carrillo, H R; Hernández-Dávila, V M; Aguilar, F; Paredes, L; Rivera, T

    2014-01-01

    The neutron spectra have been measured in two beam ports, one radial and another tangential, of the TRIGA Mark III nuclear reactor from the National Institute of Nuclear Research in Mexico. Measurements were carried out with the reactor core loaded with high enriched uranium fuel. Two reactor powers, 5 and 10 W, were used during neutron spectra measurements using a Bonner sphere spectrometer with a (6)LiI(Eu) scintillator and 2, 3, 5, 8, 10 and 12 in.-diameter high-density polyethylene spheres. The neutron spectra were unfolded using the NSDUAZ unfolding code. For each spectrum total flux, mean energy and ambient dose equivalent were determined. Measured spectra show fission, epithermal and thermal neutrons, being harder in the radial beam port. PMID:23746708

  15. Archaeometric studies by using neutron radiography in ITU TRIGA Mark-II reactor

    Archaeometric many studies have been done by using neutron radiography in ITU TRIGA Mark-II Training and Research Reactor for over 15 years. Tangential beam tube has been arranged for using neutron radiography. Generally, transfer technique has been preferred with using dysprosium screen, but indium screen also is used. Some studies are described which are all on the Anatolian artefacts. The first study from 13th century AD deals with Seljukian period from south-east Anatolia. It investigated a plate from Great Mosque door in Cizre. With means of the neutron radiography painting traces are investigated on the plates. Organic dye traces are noticed on some of plates, which have generally animal figures. Other studies from Urartu period at the first millennium B.C, investigates artefacts found at the vicinity of Van on east Anatolia. An important one is a sword that was found in a grave. It has some corrosion defects. The neutron radiography was applied and shown that wooden parts are there. Other studies referred to samples from the Ikiztepe Excavation site on north Anatolia. Many artefacts were examined by neutron radiography. Some of them evidenced animal parts are recognised as covering parts. An interesting result was obtained to a sword and its sheath that were corroded together. After the neutron radiography applications, it was noticed that there are a cloth between the sword and its sheath. Hence, it was the cause of corrosion of the artefact. By using neutron radiography, many interesting and detailed results were observed by means of the neutron beam from the ITU TRIGA Mark-II Training and Research Reactor. Some of them could not be evidenced by means of any other technique

  16. Neutron radiography applications in I.T.U. TRIGA Mark-II reactor

    Neutron radiography is an important radiographic technique which is supplied different and advanced information according to the X or gamma ray radiography. However, it has a trouble for supplying the convenient neutron sources. Tangential beam tube of Istanbul Technical University (ITU) TRIGA Mark-II Training and Research Reactor has been arranged for using neutron radiography. The neutron radiography set defined as detailed for the application of the technique. Two different techniques for neutron radiography are defined as namely, transfer method and direct method. For the transfer method dysprosium and indium screens are used in the study. But, dysprosium generally was preferred in many studies in the point of view nuclear safety. Gadolinium was used for direct method. Two techniques are compared and explained the preferring of the transfer technique. Firstly, reference composition is prepared for seeing the differences between neutron and X-ray or gamma radiography. In addition of it, some radiograph samples are given neutron and X-ray radiography which shows the different image characters. Lastly, some examples are given from archaeometric studies. One of them the brass plates of Great Mosque door in Cizre. After the neutron radiography application, organic dye traces are noticed. Other study is on a sword that belong to Urartu period at the first millennium B.C. It is seen that some wooden part on it. Some different artefacts are examined with neutron radiography from the Ikiztepe excavation site, then some animal post parts are recognized on them. One of them is sword and sheath which are corroded together. After the neutron radiography application, it can be noticed that there are a cloth between the sword and its sheath. By using neutron radiography, many interesting and detailed results are observed in ITU TRIGA Mark-II Training and Research Reactor. Some of them shouldn't be recognised by using any other technique

  17. Subchannel analysis of fuel temperature and departure of nucleate boiling of TRIGA Mark I

    Highlights: • Developed a steady-state subchannel code for the TRIGA Mark I. • Assessed natural convection correlations for steady-state operations. • Methodology outlined for gap conductance model development. • Validated subchannel code to a wide range of operating conditions. - Abstract: An evaluation of fuel temperature and departure of nucleate boiling as a function of bulk pool temperature was performed at the Texas A and M University Nuclear Science Center’s TRIGA Mark I reactor. A subchannel analysis code was written with the support of experimentally determined correlations, including the development of a gap conductance model. The code was validated for predicting peak fuel temperature at all operational power levels. The peak fuel temperature was calculated using different correlations for forced and natural convection flows for pool temperatures of 30 °C and 60 °C. The forced convection correlation predicted a fuel temperature rise of 2 °C for the difference in pool temperatures, contrary to the predicted rise of 26 °C from natural convection relationships. Experimental data shows that the relationship of fuel temperature rise with increasing pool temperature is more accurately represented by the natural convection correlation. The peak fuel temperature, for the validated natural convection relationship, is predicted to be 441 °C and 457 °C at a pool temperature of 30 °C and 60 °C, respectively. The minimum departure of nucleate boiling ratio is calculated as 2.14 and 1.72 for a pool temperature of 30 °C and 60 °C, respectively, using the Bernath correlation

  18. A digital data acquisition and display system for ITU TRIGA Mark II reactor

    Full text: In this study, a digital data acquisition and display system realized for ITU TRIGA Mark-II Reactor is described. This system is realized in order to help the reactor operator and to increase reactor console capacity. The system consists of two main units, which are host computers and RTI-815F, analog devices, data acquisition card. RTI-815F is multi-function analog/digital input/output board that plugs into one of the available long expansion slots in the IBM-PC, PC/XT, PC/AT, or equivalent personal computers. It has 16 analog input channels for single-ended input signals or 8 analog input channels for differential input signals. But its channel capacity can be increased to 32 input channels for single-ended input signals or 16 input channels for differential input signals. RTI-815F board contains 2 analog output channels, 8 digital input channels and 8 digital output channels. In the ITD TRIGA Mark-II Reactor, 6 fuel temperature channels, 3 water temperature channels, 3 control rod position channels and 4 power channels are chosen as analog input signals for RTI-815F. Its digital outputs are assigned to cooling tower fan, primary and secondary pump reactor scram, control rod rundown. During operation, data are automatically archived to disk and displayed on screen. The channel selection time and sampling time can be adjusted. The simulated movement and position of control rods in the reactor core can be noted and displayed. The changes of power, fuel temperature and water temperature can be displayed on the screen as a graphic. In this system both period and reactivity are calculated and displayed on the screen. (authors)

  19. Adaptive fuzzy control of neutron power of the TRIGA Mark III reactor; Control difuso adaptable de la potencia neutronica del reactor Triga Mark III

    Rojas R, E.

    2014-07-01

    The design and implementation of an identification and control scheme of the TRIGA Mark III research nuclear reactor of the Instituto Nacional de Investigaciones Nucleares (ININ) of Mexico is presented in this thesis work. The identification of the reactor dynamics is carried out using fuzzy logic based systems, in which a learning process permits the adjustment of the membership function parameters by means of techniques based on neural networks and bio-inspired algorithms. The resulting identification system is a useful tool that allows the emulation of the reactor power behavior when different types of insertions of reactivity are applied into the core. The identification of the power can also be used for the tuning of the parameters of a control system. On the other hand, the regulation of the reactor power is carried out by means of an adaptive and stable fuzzy control scheme. The control law is derived using the input-output linearization technique, which permits the introduction of a desired power profile for the plant to follow asymptotically. This characteristic is suitable for managing the ascent of power from an initial level n{sub o} up to a predetermined final level n{sub f}. During the increase of power, a constraint related to the rate of change in power is considered by the control scheme, thus minimizing the occurrence of a safety reactor shutdown due to a low reactor period value. Furthermore, the theory of stability in the sense of Lyapunov is used to obtain a supervisory control law which maintains the power error within a tolerance region, thus guaranteeing the stability of the power of the closed loop system. (Author)

  20. Thermo-hydrodynamic design and safety parameter studies of the TRIGA MARK II research reactor

    The PARET computer code was used to analyse important thermo-hydrodynamic design and safety parameters of the 3 MW TRIGA MARK II research reactor at Atomic Energy Research Establishment (AERE), Savar, Dhaka, Bangladesh. The study involves the determination of the departure from nucleate boiling (DNB) value and studying its effect over the thermo-hydrodynamic design of the reactor. In the process the temperature profile, heat flux and pressure drop across the hottest channel of the TRIGA core were evaluated. The DNB ratio (DNBR), which is defined as the ratio of the critical heat flux to the heat flux achieved in the core, was computed by means of a suitable correlation as defined in PARET code. Over the length 0.381 m of the hottest channel the DNBR varies, starting from 3.8951 to 5.4031, with a minimum of 2.7851. The peak heat flux occurs at the axial centre of the fuel elements; therefore the DNBR is minimum at this location. The reactor core should be designed so as to prevent the DNBR from dropping below a chosen value under a high heat flux transient condition for the most adverse set of mechanical and coolant conditions. The loss-of-flow accident (LOFA) scenario of the reactor has also been studied to ensure that the existing design and procedures are adequate to assure that the consequences from this anticipated occurrence does not lead to a significant accident. The loss-of-flow transient after a trip time of 4.08 s at 85% of loss of normal flow for the TRIGA core shows a peak temperature of 709.22 deg. C in the fuel centreline and 131.94 deg. C in the clad and 46.63 deg. C in the coolant exit of the hottest channel. The transient was terminated at 15% of nominal flow after ∼48.0 s and the time at which the reversal of coolant flow starts is ∼67.0 s

  1. Spent Fuel Management Program in the 3MW TRIGA MARK-II Research Reactor of Bangladesh

    Bangladesh Atomic Energy Commission (BAEC) has been operating a 3 MW TRIGA MARK II research reactor since 1986. The reactor was installed in the campus of the Atomic Energy Research Establishment (AERE) at Savar, Dhaka. It is one of the main nuclear research facilities in the country. The reactor uses TRIGA LEU fuel with uranium content of 20% by weight. The enrichment level of the fuel is 19.7%. The reactor has so far been operated for 7834 hours with a total cumulative burn up of 15898 MWh (662.5 MWd). The total burn up life of the present core is 1200 MWd. The main areas of use are: training of man-power for nuclear power plant applications, radioisotope (RI) production, neutron activation analysis (NAA), neutron radiography (NR) and neutron scattering. The government of Bangladesh has taken decision to establish nuclear power programme in the country. There is an ADP (Annual Development Project) to accomplish necessary activities for construction of medium size nuclear power plant (NPP) in the western zone of the country. Now, with regard to the safe management, storage of spent fuel and disposal of radioactive waste arising from operation of the research reactor and also from the proposed NPP expected to be constructed in future, BAEC is drawing up short and long-term plans and programs. At present, there does not exist any spent fuel element in the reactor facility. It is to be mentioned that Bangladesh is aware of the US DOE’s ‘Take Back Program’ in connection with the research reactor spent fuel of US origin, and is very much interested to take part in this program. The paper presents the current status of handling and storage facilities available for spent fuel and strategy for the safe management of spent fuel to be generated from the research reactor in near future. (author)

  2. TRIGA reactor main systems

    This module describes the main systems of low power (<2 MW) and higher power (≥2 MW) TRIGA reactors. The most significant difference between the two is that forced reactor cooling and an emergency core cooling system are generally required for the higher power TRIGA reactors. However, those TRIGA reactors that are designed to be operated above 3 MW also use a TRIGA fuel that is specifically designed for those higher power outputs (3 to 14 MW). Typical values are given for the respective systems although each TRIGA facility will have unique characteristics that may only be determined by the experienced facility operators. Due to the inherent wide scope of these research reactor facilities construction and missions, this training module covers those systems found at most operating TRIGA reactor facilities but may also discuss non-standard equipment that was found to be operationally useful although not necessarily required. (author)

  3. Applicable regulations and development of surveillance experiments of criticality approach in the TRIGA III Mark reactor; Normativa aplicable y desarrollo de experimentos de vigilancia de aproximacion a criticidad en el reactor Triga Mark III

    Gonzalez M, J.L.; Aguilar H, F.; Rivero G, T.; Sainz M, E. [Instituto nacional de Investigaciones Nucleares, Departamento de Automatizacion, A.P. 18-1027, Col. Escandon, 11801 Mexico D.F. (Mexico)

    2000-07-01

    In the procedure elaborated to repair the vessel of TRIGA III Mark reactor is required to move toward two tanks of temporal storage the fuel elements which are in operation and the spent fuel elements which are in decay inside the reactor pool. The National Commission of Nuclear Safety and Safeguards (CNSNS) has requested as protection measure that it is carried out a surveillance of the criticality approach of the temporal storages. This work determines the main regulation aspects that entails an experiment of criticality approach, moreover, informing about the results obtained in the developing of this experiments. The regulation aspects are not exclusives for this work in the TRIGA Mark III reactor but they also apply toward any assembling of fissile material. (Author)

  4. Plan for the safe decommissioning of the BAEC 3MW TRIGA MARK-II research reactor

    The 3 MW TRIGA Mark-II research reactor of Bangladesh Atomic Energy Commission (BAEC) has been operating since September 14, 1986. The reactor is used for radioisotope production (131I, 99mTc, 46Sc), various R and D activities, and manpower training. The reactor has been operated successfully since it's commissioning with the exception of a few reportable incidents. Of these, the decay tank leakage incident of 1997 is considered to be the most significant one. As a result of this incident, reactor operation at full power remained suspended for about 4 years. However, the reactor operation was continued during this period at a power level of 250 kW to cater the needs of various R and D groups, which required lower neutron flux for their experiments. This was made possible by establishing a temporary by pass connection across the decay tank using local technology. The reactor was made operational again at full power after successful replacement of the damaged decay tank in August 2001. At present the reactor is operated 5 days a week at a full power level of 3 MW for production of I-131 and R and D purposes. Up to December 2005 total burn-up of the core stands at about 358 Megawatt Days (MWDs). BAEC has planned to increase the production of 131I and as such, the core burn-up is expected to be increased very significantly in the years to come. There is a declaration from the US DOE that all US origin research reactor spent fuel generated within 2006 will be taken away to the USA at their own cost within 2009. But the fuel burn up of the BAEC research reactor is about 6%. So the reactor can operate for about 10-20 years more. An initial decommissioning plan for the BAEC TRIGA reactor and relevant facilities should be established as early as possible as recommended in the IAEA Safety Standards Series No.WS-G-2.1 (Decommissioning of Nuclear Power Plants and Research Reactors - Safety Standards Series No.WS-G-2.1, IAEA, Vienna, 1999). During the design and construction

  5. Calculation of neutron flux in PUSPATI TRIGA MARK II reactor using Monte-Carlo n-particle approach

    A Monte Carlo simulation of neutron flux at the TRIGA MARK II PUSPATI (RTP) nuclear research reactor at Agensi Nuklear Malaysia was carried out using the MCNP5 program. The objective of the work is to simulate the neutron flux inside the reactor core. Calculations of neutron flux for fast and thermal neutron were carried out under the conditions in which the control rod was either fully withdrawn from or fully inserted into the reactor. (Author)

  6. Characterization of control rod worths and fuel rod power peaking factors in the university of Utah TRIGA Mark I reactor

    Alroumi Fawaz; Kim Donghoon; Schow Ryan; Jevremovic Tatjana

    2016-01-01

    Control rod reactivity (worths) for the three control rods and fuel rod power peaking factors in the University of Utah research reactor (100 kW TRIGA Mark I) are characterized using the AGENT code system and the results described in this paper. These values are compared to the MCNP6 and existing experimental measurements. In addition, the eigenvalue, neutron spatial flux distributions and reaction rates are analyzed and discussed. The AGENT code system is ...

  7. Neutron spectra in two beam ports of the TRIGA Mark III reactor

    The neutron spectra have been measured in two beam ports, radial and tangential, of the TRIGA Mark III nuclear reactor from the National Institute of Nuclear Research. Measurements were carried out with the core with mixed fuel (Leu 8.5/20 and Flip Heu 8.5/70). Two reactor powers, 5 and 10 W, were used during neutron spectra measurements using a Bonner sphere spectrometer with a 6Lil(Eu) scintillator and 2, 3, 5, 8, 10 and 12 inches-diameter high density polyethylene spheres. The neutron spectra were unfolded using the NSDUAZ unfolding code; from each spectrum the total neutron flux, the neutron mean energy and the neutron ambient dose equivalent dose were determined. Measured spectra show fission (E≥ 0.1 MeV), epithermal (from 0.4 eV up to 0.1 MeV) and thermal neutrons (E≤ 0.4 eV). For both reactor powers the spectra in the radial beam port have similar features which are different to the neutron spectrum characteristics in the tangential beam port. (Author)

  8. Operational Experience with the TRIGA Mark II Reactor of the University of Pavia

    The Laboratory of Applied Nuclear Energy (LENA) is an Interdepartmental Research Centre of the University of Pavia which operates a 250 kW TRIGA Mark II Research Nuclear Reactor, a Cyclotron for the production of radioisotopes and other irradiation facilities. The reactor is in operation since 1965 and many home-made upgrading were realized in the past years in order to assure a continuous operation of the reactor for the future. The annual reactor operational time at nominal power is in the range of 300 - 400 hours depending upon the time schedule of some experiments and research activities. The reactor is mainly used for NAA activities, BNCT research, samples irradiation and training. In specific, few tens of hours of reactor operation per year are dedicated to training courses for University students and for professionals. Besides, the LENA Centre hosts every year more than one thousand high school students in visit. Lately, LENA was certified ISO 9001:2008 for the ''operation and maintenance of the reactor'' and for the ''design and delivery of the irradiation service''. Nowadays the reactor shows a good technical state and, at the moment, there are no political or economical reason to consider the reactor shut-down. (author)

  9. Renewal and upgrading of the TRIGA Mark II research reactor in Ljubljana

    Despite regulatory supervision, the owner/operator is directly responsible for safe operation of the reactor. Therefore, at the 250 kW TRIGA Mark II research reactor in Ljubljana ever since the beginning of the operation in 1966 gradually modification and modernization have been taking place. During the last twenty years many improvements were introduced, such as: - a dry central thimble for target irradiations (isotope production) - a new pneumatic facility for loading and unloading samples in a new rotary specimen rack or the central thimble - automatic data logging by a configuration based on two microcomputers (already in 1978) - a new analog instrumentation for the nuclear channels, a water level indicator, an integrator (digital power meter) and a reactivity meter - a new spent fuel storage. Further more, it was decided in 1989 to upgrade our reactor for pulsing mode operation and pulse registration. The technical experience that has taken place during the last 25 years was utilized in planning and installing a new control console, and to develop a sophisticated system for the pulse mode operation. (orig.)

  10. Design of a PGAA Facility at the TRIGA Mark III of ININ, Mexico

    A thermal neutron prompt gamma activation analysis (PGAA) facility is being developed at the TRIGA-Mark III research reactor, located at the Nabor Carrillo Nuclear Center of the Mexican Institute for Nuclear Research. The PGAA facility is to be built at the exit of a 3.9-m-long radial beam port, which pierces the graphite core reflector. The measured thermal neutron flux at the beam port exit is 0.7 x 108 n/cm2s, with an epithermal neutron flux of 0.66 x 108 n/cm2s and a gamma-ray dose of 0.1 Sv/h at full reactor power. Under these circumstances, the extraction of a suitable thermal neutron beam becomes quite challenging. The neutron beam filtering and collimation systems are to be designed for a substantial reduction of the background source components in order to maximize the usable thermal neutron intensity. To obtain reasonable PGAA performance from a filtered low-intensity thermal neutron beam, a Compton suppression feature is added to the detection system. Representative suppressed and unsuppressed spectra of paraffin (hydrogen) neutron capture gamma rays are shown

  11. Neutron detection of the Triga Mark III reactor, using nuclear track methodology

    Espinosa, G., E-mail: espinosa@fisica.unam.mx; Golzarri, J. I. [Instituto de Física, Universidad Nacional Autónoma de México Circuito de la Investigación Científica, Ciudad Universitaria. México, DF (Mexico); Raya-Arredondo, R.; Cruz-Galindo, S. [Instituto Nacional de Investigaciones Nucleares (Mexico); Sajo-Bohus, L. [Universidad Simón Bolivar, Laboratorio de Física Nuclear, Caracas (Venezuela, Bolivarian Republic of)

    2015-07-23

    Nuclear Track Methodology (NTM), based on the neutron-proton interaction is one often employed alternative for neutron detection. In this paper we apply NTM to determine the Triga Mark III reactor operating power and neutron flux. The facility nuclear core, loaded with 85 Highly Enriched Uranium as fuel with control rods in a demineralized water pool, provide a neutron flux around 2 × 10{sup 12} n cm{sup −2} s{sup −1}, at the irradiation channel TO-2. The neutron field is measured at this channel, using Landauer{sup ®} PADC as neutron detection material, covered by 3 mm Plexiglas{sup ®} as converter. After exposure, plastic detectors were chemically etched to make observable the formed latent tracks induced by proton recoils. The track density was determined by a custom made Digital Image Analysis System. The resulting average nuclear track density shows a direct proportionality response for reactor power in the range 0.1-7 kW. We indicate several advantages of the technique including the possibility to calibrate the neutron flux density measured at low reactor power.

  12. Utilization and operating experience of the TRIGA Mark II research reactor in Ljubljana

    Dimic, V. (J. Stefan Institute, Ljubljana (Slovenia))

    1999-12-15

    The operating experience of the 250 kW TRIGA Mark-II reactor of the J. Stefan Institute in Ljubljana, Slovenia in the years 1996 and 1997 is reported. The reactor has been in operation without long undesired shut-down. In 1996 the production of energy was 401 MWh (around 1600 hours in operation) and there was 7 unplanned shut-downs because of electricity broke down. In 1997 the production of energy was 272 MWh (around 1090 hours in operation). In 1991 and 1997 the reactor was almost completely reconstructed and upgraded. The reconstruction consisted mainly of replacing the grid plates, the control rod mechanisms and the control unit. Recently, the new PC based system was adopted and developed to collect the operational radiation data of the reactor. The new wiring of the electric power system, part of the primary and secondary coolant system piping and the spent fuel storage pool have been modified and the new air-exchange system in the control room were installed. Because of this large reconstruction of the reactor, for the last years in the operation of the reactor no significant problems have been detected. The facility is expected to operate without major investment at least until 2006. The reactor has been utilized in the projects: Neutron activation analysis, Boron neutron capture therapy, Real time neutron radiography, Neutron tomography, and Dosimetry research. The activities of neutron activation analysis, neutron radiography and tomography as well as boron neutron capture therapy are shortly presented

  13. Neutronic Analysis of the Pavia University TRIGA Mark II Reactor Core

    Tigliole, A. Borio Di [University of Pavia, Department of Nuclear and Theoretical Physics, Via Bassi 4, 27100 Pavia (Italy); University of Pavia, Laboratory of Applied Nuclear Energy, Via Aselli 41, 27100 Pavia (Italy); Cammi, A. [Polytechnic of Milano, Department of Energy, Via La Masa 34, 20156 Milano (Italy); Chiesa, D.; Clemenza, M. [University of Milano-Bicocca, Physics Department, Piazza della Scienza 3, 20126, Milano (Italy); Pattavina, L.; Previtali, E. [University of Milano-Bicocca, Physics Department, Piazza della Scienza 3, 20126, Milano (Italy); INFN section of Milano-Bicocca, Piazza della Scienza 3, 20126, Milano (Italy); Scian, G. [University of Pavia, Laboratory of Applied Nuclear Energy, Via Aselli 41, 27100 Pavia (Italy)

    2011-07-01

    An advanced computational tool based on Monte Carlo code was developed for the neutronic analysis of the TRIGA Mark II research reactor of the University of Pavia and the results from simulations were benchmarked with the experimental data. The neutron analysis was performed by means of the 3-D continuous-energy Monte Carlo codes MCNP4C and MCNP5. All core components were reproduced in good detail and the model allows the description of different core and fuel configurations with good versatility. In a first step, the results from the simulations with fresh fuel at room temperature were compared with the experimental data about critical core parameters at zero power level, quoted in the reactor First Criticality Final Report; a very good agreement was found and the goodness of the model was proved. Afterwards, neutron flux and reactivity dependence on the fuel and moderator temperature was studied in detail; all the available methods for the simulation of thermal effects were analyzed in order to model the reactor in the stationary operating condition at 250 kW. The model was updated to the present configuration and the use of specific S({alpha},{beta}) cross sections was found to be of primary importance for a correct simulation of low-energy neutrons scattering within moderator. (author)

  14. Neutronic Analysis of the Pavia University TRIGA Mark II Reactor Core

    An advanced computational tool based on Monte Carlo code was developed for the neutronic analysis of the TRIGA Mark II research reactor of the University of Pavia and the results from simulations were benchmarked with the experimental data. The neutron analysis was performed by means of the 3-D continuous-energy Monte Carlo codes MCNP4C and MCNP5. All core components were reproduced in good detail and the model allows the description of different core and fuel configurations with good versatility. In a first step, the results from the simulations with fresh fuel at room temperature were compared with the experimental data about critical core parameters at zero power level, quoted in the reactor First Criticality Final Report; a very good agreement was found and the goodness of the model was proved. Afterwards, neutron flux and reactivity dependence on the fuel and moderator temperature was studied in detail; all the available methods for the simulation of thermal effects were analyzed in order to model the reactor in the stationary operating condition at 250 kW. The model was updated to the present configuration and the use of specific S(α,β) cross sections was found to be of primary importance for a correct simulation of low-energy neutrons scattering within moderator. (author)

  15. Operational Experience with the TRIGA Mark II Reactor of the University of Pavia

    Tigliole, A. Borio Di; Alloni, D.; Cagnazzo, M.; Coniglio, M.; Lana, F.; Losi, A.; Magrotti, G.; Manera, S.; Marchetti, F.; Pappalardo, P.; Prata, M.; Provasi, M.C.; Salvini, A.; Scian, G.; Vinciguerra, G. [University of Pavia, Laboratory of Applied Nuclear Energy (L.E.N.A), Via Aselli 41, 27100 Pavia (Italy)

    2011-07-01

    The Laboratory of Applied Nuclear Energy (LENA) is an Interdepartmental Research Centre of the University of Pavia which operates a 250 kW TRIGA Mark II Research Nuclear Reactor, a Cyclotron for the production of radioisotopes and other irradiation facilities. The reactor is in operation since 1965 and many home-made upgrading were realized in the past years in order to assure a continuous operation of the reactor for the future. The annual reactor operational time at nominal power is in the range of 300 - 400 hours depending upon the time schedule of some experiments and research activities. The reactor is mainly used for NAA activities, BNCT research, samples irradiation and training. In specific, few tens of hours of reactor operation per year are dedicated to training courses for University students and for professionals. Besides, the LENA Centre hosts every year more than one thousand high school students in visit. Lately, LENA was certified ISO 9001:2008 for the ''operation and maintenance of the reactor'' and for the ''design and delivery of the irradiation service''. Nowadays the reactor shows a good technical state and, at the moment, there are no political or economical reason to consider the reactor shut-down. (author)

  16. Neutron spectra in two beam ports of the TRIGA Mark III reactor

    Vega C, H. R.; Hernandez D, V. M. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98060 Zacatecas (Mexico); Aguilar, F.; Paredes, L. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Rivera M, T., E-mail: fermineutron@yahoo.com [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Unidad Legaria, Av. Legaria 694, 11500 Mexico D. F. (Mexico)

    2013-10-15

    The neutron spectra have been measured in two beam ports, radial and tangential, of the TRIGA Mark III nuclear reactor from the National Institute of Nuclear Research. Measurements were carried out with the core with mixed fuel (Leu 8.5/20 and Flip Heu 8.5/70). Two reactor powers, 5 and 10 W, were used during neutron spectra measurements using a Bonner sphere spectrometer with a {sup 6}Lil(Eu) scintillator and 2, 3, 5, 8, 10 and 12 inches-diameter high density polyethylene spheres. The neutron spectra were unfolded using the NSDUAZ unfolding code; from each spectrum the total neutron flux, the neutron mean energy and the neutron ambient dose equivalent dose were determined. Measured spectra show fission (E≥ 0.1 MeV), epithermal (from 0.4 eV up to 0.1 MeV) and thermal neutrons (E≤ 0.4 eV). For both reactor powers the spectra in the radial beam port have similar features which are different to the neutron spectrum characteristics in the tangential beam port. (Author)

  17. A sipping test system to the Triga Mark I IPR-R1 reactor

    The IPR-R1 TRIGA MARK I Research Reactor of the Nuclear Technology Development Centre (CDTN/CNEN-MG) is a tank type reactor of General Atomic Company that has been operating since 1960 at a power of 100 kW. At present there are 63 fuel rods at the reactor core (58 aluminum cladding, 5 stainless steel and 1 stainless steel instrumented). The oldest fuel elements are made with aluminum alloy and the new ones from stainless steel. Some of the old fuel rods present some spots along their lateral fuel plates. These spots are originated by galvanic corrosion between the fuel cladding and the aluminum core grid. To provide an ageing program to the reactor, a sipping tests system will be performed with the reactor fuel. The system intends evaluate the possible presence of 137Cs leaking rate. This work presents the system, the procedure and methodology that will is used to perform the sipping tests with the fuel rods at the reactor core. The results obtained for the 137Cs sipping water activity for some fuel assembly, if any, will be evaluated with the system in operation. A correlation between the possible corrosion and the activity values measured will be realized. (author)

  18. Immobilization of Ion Exchange radioactive resins of the TRIGA Mark III Nuclear Reactor

    In the last decades many countries in the world have taken interest in the use, availability, and final disposal of dangerous wastes in the environment, within these, those dangerous wastes that contain radioactive material. That is why studies have been made on materials used as immobilization agent of radioactive waste that may guarantee its storage for long periods of time under drastic conditions of humidity, temperature change and biodegradation. In mexico, the development of different applications of radioactive material in the industry, medicine and investigation, have generated radioactive waste, sealed and open sources, whose require a special technological development for its management and final disposal. The present work has as a finality to develop the process and define the agglutinating material, bitumen, cement and polyester resin that permits immobilization of resins of Ionic Exchange contaminated by Barium 153, Cesium 137, Europium 152, Cobalt 60 and Manganese 54 generated from the nuclear reactor TRIGA Mark III. Ionic interchange contaminated resin must be immobilized and is analysed under different established tests by the Mexican Official Standard NOM-019-NUCL-1995 Low level radioactive wastes package requirements for its near-surface final disposal. Immobilization of ionic interchange contaminated resins must count with the International Standards applicable in this process; in these standards, the following test must be taken in prototype examples: Free-standing water, leachability, compressive strength, biodegradation, radiation stability, thermal stability and burning rate. (Author)

  19. IPR-RI TRIGA MARK I reactor and the neutron activation analysis at CDTN/CNEN

    The IPR-R1 TRIGA Mark I research reactor started up in 1960. It is located at Centro de Desenvolvimento da Tecnologia Nuclear (Nuclear Technology Development Centre) / Comissao Nacional de Energia Nuclear (Brazilian Commission for Nuclear Energy), CDTN/CNEN. Join to the reactor, the Laboratory for Neutron Activation Analysis has been developing its activities since 1960. The activities of the Laboratory comprise the delayed fission neutron activation analysis, instrumental (comparative and parametric methods) and radiochemical / chemical methods. These methods are responsible for relevant percentage of CDTN's analysis demand, meeting the clients' analytical needs and researches developed by the Laboratory, by CDTN and by other institutions. Over the years the work has been linked to the goals of the country and the institutions. Nowadays several elements - Ag, Al, Au, As, Ba, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Eu, Fe, Ga, Hf, Hg, Ho, K, La, Mg, Mn, Mo, Na, Nd, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, U, V, W, Yb, Zn and Zr - are determined in several matrices and range of concentrations. In Brazil, CDTN is the only Institute that fully masters the instrumental neutron activation analysis k0-method determining short, medium and long half-life radionuclides using its own nuclear reactor. The good performance of the reactor is pointed out in a table with experimental and certified values for Certified Reference Materials. (authors)

  20. Visualization of neutron flux and power distributions in TRIGA Mark II reactor as an educational tool

    Modern Monte Carlo computer codes (e.g. MCNP) for neutron transport allow calculation of detailed neutron flux and power distribution in complex geometries with resolution of ∼1 mm. Moreover they enable the calculation of individual particle tracks, scattering and absorption events. With the use of advanced software for 3D visualization (e.g. Amira, Voxler, etc.) one can create and present neutron flux and power distribution in a 'user friendly' way convenient for educational purposes. One can view axial, radial or any other spatial distribution of the neutron flux and power distribution in a nuclear reactor from various perspectives and in various modalities of presentation. By visualizing the distribution of scattering and absorption events and individual particle tracks one can visualize neutron transport parameters (mean free path, diffusion length, macroscopic cross section, up-scattering, thermalization, etc.) from elementary point of view. Most of the people remember better, if they visualize the processes. Therefore the representation of the reactor and neutron transport parameters is a convenient modern educational tool for the (nuclear power plant) operators, nuclear engineers, students and specialists involved in reactor operation and design. The visualization of neutron flux and power distributions in Jozef Stefan Institute TRIGA Mark II research reactor is treated in the paper. The distributions are calculated with MCNP computer code and presented using Amira and Voxler software. The results in the form of figures are presented in the paper together with comments qualitatively explaining the figures. (authors)

  1. Conversion of the core of the TRIGA Mark III reactor at the Mexican Nuclear Centre

    It was decided to convert the core of the TRIGA MARK III reactor at the Mexican Nuclear Centre run by the National Nuclear Institute because of problems detected during the operation, such as a lack of excess reactivity for operation at nominal power over long periods and difficulties in the maintenance and calibration of the control panel. In order to compensate for the lack of excess reactivity the fuel elements taken to the highest burnup were replaced by fresh elements acquired for this purpose. The latter, however, had a different enrichment, and this necessitated a detailed analysis of the neutronic and thermohydraulic behaviour of the reactor with a view to determining a mixed core configuration which would meet safe operation requirements. In conducting the thermohydraulic analysis, a natural convection coolant flow model was developed to determine coolant velocity and pressure drop patterns within the core. The heat transfer equations were solved and it was found that the hottest fuel element did not attain critical heat flux conditions. In loading this core it was also necessary to analyse procedures and to consider the possible effects of reaching criticality with fuel elements having different enrichments. The loading procedure is described, as is the measurement system and the results obtained. In order to resolve the calibration and maintenance problems, a new, more advanced control panel was designed with conventional and nuclear detection systems and modern components

  2. Neutron detection of the Triga Mark III reactor, using nuclear track methodology

    Nuclear Track Methodology (NTM), based on the neutron-proton interaction is one often employed alternative for neutron detection. In this paper we apply NTM to determine the Triga Mark III reactor operating power and neutron flux. The facility nuclear core, loaded with 85 Highly Enriched Uranium as fuel with control rods in a demineralized water pool, provide a neutron flux around 2 × 1012 n cm−2 s−1, at the irradiation channel TO-2. The neutron field is measured at this channel, using Landauer® PADC as neutron detection material, covered by 3 mm Plexiglas® as converter. After exposure, plastic detectors were chemically etched to make observable the formed latent tracks induced by proton recoils. The track density was determined by a custom made Digital Image Analysis System. The resulting average nuclear track density shows a direct proportionality response for reactor power in the range 0.1-7 kW. We indicate several advantages of the technique including the possibility to calibrate the neutron flux density measured at low reactor power

  3. Determination of irradiation doses in the TRIGA Mark II by Fricke dosimetry

    One of the most frequently applied aqueous chemical systems for measuring radiation doses is the Fricke dosimeter. In this system a 10-3 molar solution of ferrous sulphate in air saturated 0,8 molar sulphuric acid is oxidated to ferric sulphate. Only freshly prepared solutions had been used or corrections had been made for the rate of auto oxidation in the stored solutions. The determination of ferric ion yield may either be done by spectrophotometric or potentiometric measurements of the irradiated solution. The dosimetric range of the solution is about 5.102 to 5.104 rad. The measurements of radiation doses by the method can be done very easily and quickly and with good reproducibility. With this simple technique it is possible to make dosimetric measurements even during the irradiation. In this paper results are mentioned which are obtained by experiments with gamma radiation and by irradiation in the TRIGA Mark II reactor. This irradiation had been made in several positions, for instance in the water tank and in the thermal column. The difficulty of measurements in the pneumatic system or in the central thimble is the evaluation of the G-value for the mixed irradiation field. (author)

  4. Activation calculation of steel of the control rods of TRIGA Mark III reactor

    In the pool of TRIGA Mark III reactor of the Instituto Nacional de Investigaciones Nucleares (ININ), there are control rods that were removed from the core, and which are currently on shelves of decay. These rods were part of the reactor core when only had fuel standard (from 1968-1989). To conduct a proper activation analysis of the rods, is very important to have well-characterized the materials which are built, elemental composition of the same ones, the atomic densities and weight fractions of the elements that constitute them. To determine the neutron activation of the control rods MCNP5 code was used, this code allows us to have well characterized the radionuclides inventory that were formed during irradiation of the control rods. This work is limited to determining the activation of the steel that is part of the shielding of the control rods, the nuclear fuel that is in the fuel follower does not include. The calculation model of the code will be validated with experimental measurements and calculating the activity of fission products of the fuel follower which will take place at the end of 2014. (Author)

  5. Fuel burnup analysis of the TRIGA Mark II Reactor at the University of Pavia

    Chiesa, Davide; Pozzi, Stefano; Previtali, Ezio; Sisti, Monica; Alloni, Daniele; Magrotti, Giovanni; Manera, Sergio; Prata, Michele; Salvini, Andrea; Cammi, Antonio; Zanetti, Matteo; Sartori, Alberto

    2015-01-01

    A time evolution model was developed to study fuel burnup for the TRIGA Mark II reactor at the University of Pavia. The results were used to predict the effects of a complete core reconfiguration and the accuracy of this prediction was tested experimentally. We used the Monte Carlo code MCNP5 to reproduce system neutronics in different operating conditions and to analyse neutron fluxes in the reactor core. The software that took care of time evolution, completely designed in-house, used the neutron fluxes obtained by MCNP5 to evaluate fuel consumption. This software was developed specifically to keep into account some features that differentiate experimental reactors from power ones, such as the daily ON/OFF cycle and the long fuel lifetime. These effects can not be neglected to properly account for neutron poison accumulation. We evaluated the effect of 48 years of reactor operation and predicted a possible new configuration for the reactor core: the objective was to remove some of the fuel elements from the...

  6. Testing the applicability of the k 0-NAA method at the MINT's TRIGA MARK II reactor

    The Analytical Chemistry Laboratory at MINT is using the NAA technique since 1980s and is the only laboratory in Malaysia equipped with a research reactor, namely the TRIGA MARK II. Throughout the years the development of NAA technique has been very encouraging and was made applicable to a wide range of samples. At present, the k 0 method has become the preferred standardization method of NAA (k 0-NAA) due to its multi-elemental analysis capability without using standards. Additionally, the k 0 method describes NAA in physically and mathematically understandable definitions and is very suitable for computer evaluation. Eventually, the k 0-NAA method has been adopted by MINT in 2003, in collaboration with the Nuclear Research Institute (NRI), Vietnam. The reactor neutron parameters (α and f) for the pneumatic transfer system and for the rotary rack at various locations, as well as the detector efficiencies were determined. After calibration of the reactor and the detectors, the implemented k 0 method was validated by analyzing some certified reference materials (including IAEA Soil 7, NIST 1633a, NIST 1632c, NIST 1646a and IAEA 140/TM). The analysis results of the CRMs showed an average u score well below the threshold value of 2 with a precision of better than ±10% for most of the elemental concentrations obtained, validating herewith the introduction of the k 0-NAA method at the MINT

  7. Testing the applicability of the k0-NAA method at the MINT's TRIGA MARK II reactor

    Siong, Wee Boon; Dung, Ho Manh; Wood, Ab. Khalik; Salim, Nazaratul Ashifa Abd.; Elias, Md. Suhaimi

    2006-08-01

    The Analytical Chemistry Laboratory at MINT is using the NAA technique since 1980s and is the only laboratory in Malaysia equipped with a research reactor, namely the TRIGA MARK II. Throughout the years the development of NAA technique has been very encouraging and was made applicable to a wide range of samples. At present, the k0 method has become the preferred standardization method of NAA ( k0-NAA) due to its multi-elemental analysis capability without using standards. Additionally, the k0 method describes NAA in physically and mathematically understandable definitions and is very suitable for computer evaluation. Eventually, the k0-NAA method has been adopted by MINT in 2003, in collaboration with the Nuclear Research Institute (NRI), Vietnam. The reactor neutron parameters ( α and f) for the pneumatic transfer system and for the rotary rack at various locations, as well as the detector efficiencies were determined. After calibration of the reactor and the detectors, the implemented k0 method was validated by analyzing some certified reference materials (including IAEA Soil 7, NIST 1633a, NIST 1632c, NIST 1646a and IAEA 140/TM). The analysis results of the CRMs showed an average u score well below the threshold value of 2 with a precision of better than ±10% for most of the elemental concentrations obtained, validating herewith the introduction of the k0-NAA method at the MINT.

  8. Characterization of the TRIGA Mark II reactor full-power steady state

    Cammi, Antonio; Chiesa, Davide; Clemenza, Massimiliano; Pozzi, Stefano; Previtali, Ezio; Sisti, Monica; Magrotti, Giovanni; Prata, Michele; Salvini, Andrea

    2015-01-01

    In this work, the characterization of the full-power steady state of the TRIGA Mark II nuclear reactor of the University of Pavia is performed by coupling Monte Carlo (MC) simulation for neutronics with "Multiphysics" model for thermal-hydraulics. Neutronic analyses have been performed starting from a MC model of the entire reactor system, based on the MCNP5 code, that was already validated in fresh fuel and zero-power configuration (in which thermal effects are negligible) using the available experimental data as benchmark. In order to describe the full-power reactor configuration, the temperature distribution in the core is necessary. To evaluate it, a thermal-hydraulic model has been developed, using the power distribution results from MC simulation as input. The thermal-hydraulic model is focused on the core active region and takes into account sub-cooled boiling effects present at full reactor power. The obtained temperature distribution is then introduced in the MC model and a benchmark analysis is carr...

  9. Utilization and operating experience of the 250 kw TRIGA Mark II research reactor in Ljubljana

    In its 35th year, the TRIGA Mark II 250 kW pulsing research reactor in Ljubljana is continuing its busy operation. With the maximum neutron flux in the central thimble of 10 13 n/cm 2 sec and many sample radiation positions the reactor has been used to perform many experiments in the following fields: solid state physics (elastic and inelastic neutron scattering), neutron dosimetry, neutron radiography, reactor physics including burn up measurements and calculations, boron neutron capture therapy and neutron activation analysis which represents one of the major usage of our reactor. Besides these, applied research around the reactor has been conducted, such as doping of silicon monocrystals, a routine production of various radioactive isotopes for industry ( 60Co, 64Zn, 24Na, 82Br) and medical use ( 18F, 99m Tc, etc.) and other activities. During the past decade the reactor was almost completely reconstructed (new grid plates, the control mechanisms and the control unit, modification of the spent fuel storage pool, etc). The main novelty in the reactor physics and operation features of the reactor was the installation of a pulse rod, therefore the reactor can be operated in a pulse mode. After reconstruction, the core was loaded with fresh 20% enriched fuel elements. In 1999 all spent fuel elements were shipped to the USA. (author)

  10. Simulation of Collimator for Neutron Imaging Facility of TRIGA MARK II PUSPATI Reactor

    Zin, Muhammad Rawi Mohamed; Jamro, Rafhayudi; Yazid, Khairiah; Hussain, Hishamuddin; Yazid, Hafizal; Ahmad, Megat Harun Al Rashid Megat; Azman, Azraf; Mohamad, Glam Hadzir Patai; Hamzah, Nai'im Syaugi; Abu, Mohamad Puad

    Neutron Radiography facility in TRIGA MARK II PUSPATI reactor is being upgraded to obtain better image resolution as well as reducing exposure time. Collimator and exposure room are the main components have been designed for fabrication. This article focuses on the simulation part that was carried out to obtain the profile of collimated neutron beam by utilizing the neutron transport protocol code in the Monte Carlo N-Particle (MCNP) software. Particular interest is in the selection of materials for inlet section of the collimator. Results from the simulation indicates that a combination of Bismuth and Sapphire, each of which has 5.0 cm length that can significantly filter both the gamma radiation and the fast neutrons. An aperture made of Cadmium with 1.0 cm opening diameter provides thermal neutron flux about 1.8 x108 ncm-2s-1 at the inlet, but reduces to 2.7 x106 ncm-2s-1 at the sample plane. Still the flux obtained is expected to reduces exposure time as well as gaining better image resolution.

  11. Utilization and operating experience of the TRIGA Mark II research reactor in Ljubljana

    The operating experience of the 250 kW TRIGA Mark-II reactor of the J. Stefan Institute in Ljubljana, Slovenia in the years 1996 and 1997 is reported. The reactor has been in operation without long undesired shut-down. In 1996 the production of energy was 401 MWh (around 1600 hours in operation) and there was 7 unplanned shut-downs because of electricity broke down. In 1997 the production of energy was 272 MWh (around 1090 hours in operation). In 1991 and 1997 the reactor was almost completely reconstructed and upgraded. The reconstruction consisted mainly of replacing the grid plates, the control rod mechanisms and the control unit. Recently, the new PC based system was adopted and developed to collect the operational radiation data of the reactor. The new wiring of the electric power system, part of the primary and secondary coolant system piping and the spent fuel storage pool have been modified and the new air-exchange system in the control room were installed. Because of this large reconstruction of the reactor, for the last years in the operation of the reactor no significant problems have been detected. The facility is expected to operate without major investment at least until 2006. The reactor has been utilized in the projects: Neutron activation analysis, Boron neutron capture therapy, Real time neutron radiography, Neutron tomography, and Dosimetry research. The activities of neutron activation analysis, neutron radiography and tomography as well as boron neutron capture therapy are shortly presented

  12. Thermal Hydraulics Analysis for the 3MW TRIGA MARK-II Research Reactor Under Transient Condition

    Some important thermal hydraulic parameters of the 3 MW TRIGA MARK-II research reactor operating under transient condition were investigated using two computer codes PULTRI and TEMPUL. Major transient parameters, such as, peak power and prompt energy released after pulse, maximum fuel and coolant temperature, surface heat flux, time and radial distribution of temperature within fuel element after pulse, fuel, fuel-cladding gap width variation, etc. were computer and compared with the experimental and operational values as reported in the safety Analysis Report (SAR). It was observed that pulsing of the reactor inserting an excess reactivity of $2.00 shoots the reactor power level to 854.353 MW compared to an experimental value of 852 MW; the maximum fuel temperature corresponding to this peak power was found to be 846.76o C which is much less than the limiting maximum value of fuel temperature of 11500 C as reported in SAR. During a pulse if the film boiling occurs for a peak adiabatic fuel temperature of 1000o C, the calculated outer cladding wall temperature was observed to be 702.390 C compared to a value of 760o C reported in SAR under the same condition. The investigated other results were also found to be in good agreement with the values reported in the SAR. 16 refs., 22 figs. (author)

  13. The future of the IPR-R1 TRIGA MARK I reactor after 48 years operation

    The TRIGA Mark I IPR-R1 Reactor operates in the Nuclear Technology Development Center/ Brazilian Committion for Nuclear Energy (CDTN/CNEN), originally Institute of Radioactive Researches, in Belo Horizonte, Minas Gerais, since November 6, 1960. Initially it operated for isotope production for different uses, being later used in wide scale for another purposes as analyses for activation with neutrons and training of nuclear power plants operators. Dozens of degree theses were also developed with the use of the reactor. Along the years, several improvements were introduced in the reactor and its auxiliary systems, with the purpose to provide better use of the facilities and with the objective to increase the safety in the operation. The reactor is ready right now to operate at 250 kW, and for sure the nuclear applications programmed will be improved. The Operation Manual and the Safety Analysis report were already modified, as well as the Emergency Plan and the relative procedures to the same. After the tests at the end of 2008, the reactor will already be operating in the new power. This work presents a description of the several accomplishments of the last years and comments about the possibility of new uses for the reactor in the several areas of nuclear applications and some of the experiments and tests results during the upgrading program. (authors)

  14. The IPR-R1 TRIGA Mark I Reactor in 39 years: Operations and general improvements

    The nuclear IPR-R1 TRIGA Mark I Reactor operating in the Nuclear Technology Development Center, originally Institute for Radioactive Research in Minas Gerais, Brazil, was dedicated in November 11, 1960. Initially operating for the production of radioisotopes for different uses, it started later to be used in large scale for neutron activation analysis and training of operators for nuclear power plants. Many improvements have been made throughout these years to provide a better performance in its operation and safety conditions. A new cooling system to operate until 300 kW, a new control rod mechanism, an aluminum tank for the reactor pool, an optimization in the pneumatic system, a new reactor control console and a general remodeling of the reactor laboratory were some of the improvements added. To prevent and mitigate the ageing effects, the reactor operation personnel is starting a program to minimize future operation problems. This paper describes the improvements made, the results obtained during the past 39 years, and the precautions taken to ensure future safe operation of the reactor to give operators better conditions of safe work. (author)

  15. Calculation analysis of TRIGA MARK II reactor core composed of two types of fuel elements

    The most important properties of mixed cores are treated for TRIGA MARK II reactor, composed of standard (20% enriched, 8.5w% U content) and FLIP (70% enriched, 8.5w% U content) fuel elements. Large difference in enrichment and presence of burnable poison in FLIP fuel have strong influence on the main core characteristics, such as: fuel temperature coefficient, power defect, Xe and Sm worth, power and flux distributions, etc. They are significantly different for both types of fuel. Optimal loading of mixed cores therefore strongly depends on the loading pattern of both types of fuel elements. Results of systematic calculational analysis of mixed cores are presented. Calculations on the level of fuel element are performed with WIMSD-4 computer code with extended cross-section library. Core calculations are performed with TRIGAP two-group 1-D diffusion code. Results are compared to measurements and physical explanation is provided. Special concern is devoted to realistic mixed cores, for which optimal in-core fuel management is derived. Refs, figs and tabs

  16. Neutron detection of the Triga Mark III reactor, using nuclear track methodology

    Espinosa, G.; Golzarri, J. I.; Raya-Arredondo, R.; Cruz-Galindo, S.; Sajo-Bohus, L.

    2015-07-01

    Nuclear Track Methodology (NTM), based on the neutron-proton interaction is one often employed alternative for neutron detection. In this paper we apply NTM to determine the Triga Mark III reactor operating power and neutron flux. The facility nuclear core, loaded with 85 Highly Enriched Uranium as fuel with control rods in a demineralized water pool, provide a neutron flux around 2 × 1012 n cm-2 s-1, at the irradiation channel TO-2. The neutron field is measured at this channel, using Landauer® PADC as neutron detection material, covered by 3 mm Plexiglas® as converter. After exposure, plastic detectors were chemically etched to make observable the formed latent tracks induced by proton recoils. The track density was determined by a custom made Digital Image Analysis System. The resulting average nuclear track density shows a direct proportionality response for reactor power in the range 0.1-7 kW. We indicate several advantages of the technique including the possibility to calibrate the neutron flux density measured at low reactor power.

  17. Triga Mark III Reactor Operating Power and Neutron Flux Study by Nuclear Track Methodology

    Espinosa, G.; Golzarri, J. I.; Raya-Arredondo, R.; Cruz-Galindo, S.; Sajo-Bohus, L.

    The operating power of a TRIGA Mark III reactor was studied using Nuclear Track Methodology (NTM). The facility has a Highly Enriched Uranium core that provides a neutron flux of around 2 x 1012 n cm-2 s-1 in the TO-2 irradiation channel. The detectors consisted of a Landauer® CR-39 (allyl diglycol polycarbonate) chip covered with a 3 mm Plexiglas® converter. After irradiation, the detectors were chemically etched in a 6.25M-KOH solution at 60±1 °C for 6 h. Track density was determined by a custom-made Digital Image Analysis System. The results show a direct proportionality between reactor power and average nuclear track density for powers in the range 0.1-7 kW. Data reproducibility and relatively low uncertainty (±3%) were achieved. NTM is a simple, fast and reliable technique that can serve as a complementary procedure to measure reactor operating power. It offers the possibility of calibrating the neutron flux density in any low power reactor.

  18. Operation and maintenance experience at the General Atomic Company's TRIGA reactor facility at San Diego, California

    Since the startup of the original 250 kW TRIGA Mark I reactor in 1958, General Atomic Company has accumulated nearly 24 years of operation and maintenance experience with this type of reactor. In addition to the nearly 24 years of experience gained on the Mark I, GA has operated the 1.5 MW Advanced Prototype Test Reactor (Mark F) for 22 years and operated a 2 MW below-ground TRIGA Mark III for five years. Information obtained from normal and abnormal operation are presented. (author)

  19. Reactor physics tests of TRIGA Mark-II Reactor in Ljubljana

    TRIGA Mark-II Reactor in Ljubljana was recently reconstructed. The reconstruction consisted mainly of replacing the grid plates, the control rod mechanisms and the control unit. The standard type control rods were replaced by the fuelled follower type, the central grid location (A ring) was adapted for fuel element insertion, the triangular cutouts were introduced in the upper plate design. However, the main novelty in reactor physics and operational features of the reactor was the installation of a pulse rod. Having no previous operational experience in pulsing, a detailed and systematic sequence of tests was defined in order to check the predicted design parameters of the reactor with measurements. The following experiments are treated in this paper: initial criticality, excess reactivity measurements, control rod worth measurement, fuel temperature distribution, fuel temperature reactivity coefficient, pulse parameters measurement (peak power, prompt energy, peak temperature). Flux distributions in steady state and pulse mode were measured as well, however, they are treated only briefly due to the volume of the results. The experiments were performed with completely fresh fuel of 12 w% enriched Standard Stainless Steel type. The core configuration was uniform (one fuel element type, including fuelled followers) and compact (no irradiation channels or gaps), as such being particularly convenient for testing the computer codes for TRIGA reactor calculations. Comparison of analytical predictions, obtained with WIMS, SLXTUS, TRIGAP and PULSTRI codes to measured values showed agreement within the error of the measurement and calculation. The paper has the following contents: 1. Introduction; 2. Steady State Experiments; 2.1. Core loading and critical experiment; 2.2. Flux range determination for tests at zero power; 2.3. Digital reactivity meter checkout; 2.4. Control rod worth measurements; 2.5. Excess reactivity measurement; 2.6. Thermal power calibration; 2

  20. Criticality calculations for the TRIGA Mark-II reactor of ITU by the finite element and finite difference methods

    In this study, TRIGA Mark-II reactor of the Istanbul Technical University is treated in cylindrical geometry. Using two-region and ten-region models C23 of this reactor, both FDM and FEM have been utilized to solve multiplication eigenvalue problems. Polynomial approximations up to degree ten have been used in the FEM solutions. Such high degree polynomial approximations are not reported in the literature, perhaps due to the difficulty of assembling the coefficient matrix. By the use of the computer also in the formulation of the problem, such high degree approximations are made possible. The relative computer execution times of FDM and various degree FEM solutions are compared and their relative merits in TRIGA calculations are assessed. Both consistent and lumped source variety FEM solutions are obtained

  1. Utilization of the 250 kW TRIGA Mark II reactor in Ljubljana. Thirty years of experiences

    In its 30th year, the TRIGA Mark II 250 kW pulsing reactor is continuing its busy operation. With the maximum neutron flux in the central thimble of 1.1013 n/cm2 sec and many sample radiation positions the reactor has been used for a number of sophisticated experiments in the following fields: solid state physics (elastic and inelastic scattering of neutrons), neutron dosimetry, neutron radiography, reactor physics including nuclear burn up measurements and calculations and neutron activation analysis which represents one of the major usage of our reactor. Besides these, applied research around the reactor has been conducted, such as dopping of silicon monocrystals, a routine production of various radioactive isotopes for industry and medical use (18F,99mTc). At the Nuclear Training Centre the TRIGA reactor is the main teaching equipment. This training centre can fulfil the training requirements of the first Slovenian Nuclear Power Plant Krsko. (orig.)

  2. Computational analysis of neutronic parameters for TRIGA Mark-II research reactor using evaluated nuclear data libraries

    The aim of this study is to analyze the neutronic parameters of TRIGA Mark-II research reactor using the chain of NJOY-WIMS-CITATION computer codes based on evaluated nuclear data libraries CENDL-2.2 and JEFF-3.1.1. The nuclear data processing code NJOY99.0 has been employed to generate the 69 group WIMS library for the isotopes of TRIGA core. The cell code WIMSD-5B was used to generate the cross sections in CITATION format and then 3-dimensional diffusion code CITTATION was used to calculate the neutronic parameters of the TRIGA Mark-II research reactor. All the analyses were performed using the 7-group macroscopic cross section library. The CITATION test-runs using different cross section sets based on different models applied in WIMS calculations have shown a strong influence of those models on the final integral parameters. Some of the cells were specially treated with PRIZE options available in WIMSD-5B to take into account the fine structure of the flux gradient in the fuel-reflector interface region. It was observed that two basic parameters, the effective multiplication factor, keff and the thermal neutron flux, were in good agreement among the calculated results with each other as well as the measured values. The maximum power densities at the hot spot were 1.0446E02 W/cc and 1.0426E02 W/cc for the libraries CENDL-2.2 and JEFF-3.1.1 respectively. The calculated total peaking factors 5.793 and 5.745 were compared to the original SAR value of 5.6325 as well as MCNP result. Consequently, this analysis will be helpful to enhance the neutronic calculations and also be used for the further thermal-hydraulics study of the TRIGA core.

  3. Computational analysis of neutronic parameters for TRIGA Mark-II research reactor using evaluated nuclear data libraries

    Uddin, M.N. [Department of Physics, Jahangirnagar University, Dhaka (Bangladesh); Sarker, M.M., E-mail: sarker_md@yahoo.co [Reactor Physics and Engineering Division, Institute of Nuclear Science and Technology, Atomic Energy Research Establishment, Ganakbari, Savar, GPO Box 3787, Dhaka-1000 (Bangladesh); Khan, M.J.H. [Reactor Physics and Engineering Division, Institute of Nuclear Science and Technology, Atomic Energy Research Establishment, Ganakbari, Savar, GPO Box 3787, Dhaka-1000 (Bangladesh); Islam, S.M.A. [Department of Physics, Jahangirnagar University, Dhaka (Bangladesh)

    2010-03-15

    The aim of this study is to analyze the neutronic parameters of TRIGA Mark-II research reactor using the chain of NJOY-WIMS-CITATION computer codes based on evaluated nuclear data libraries CENDL-2.2 and JEFF-3.1.1. The nuclear data processing code NJOY99.0 has been employed to generate the 69 group WIMS library for the isotopes of TRIGA core. The cell code WIMSD-5B was used to generate the cross sections in CITATION format and then 3-dimensional diffusion code CITTATION was used to calculate the neutronic parameters of the TRIGA Mark-II research reactor. All the analyses were performed using the 7-group macroscopic cross section library. The CITATION test-runs using different cross section sets based on different models applied in WIMS calculations have shown a strong influence of those models on the final integral parameters. Some of the cells were specially treated with PRIZE options available in WIMSD-5B to take into account the fine structure of the flux gradient in the fuel-reflector interface region. It was observed that two basic parameters, the effective multiplication factor, k{sub eff} and the thermal neutron flux, were in good agreement among the calculated results with each other as well as the measured values. The maximum power densities at the hot spot were 1.0446E02 W/cc and 1.0426E02 W/cc for the libraries CENDL-2.2 and JEFF-3.1.1 respectively. The calculated total peaking factors 5.793 and 5.745 were compared to the original SAR value of 5.6325 as well as MCNP result. Consequently, this analysis will be helpful to enhance the neutronic calculations and also be used for the further thermal-hydraulics study of the TRIGA core.

  4. Adaptive fuzzy control of neutron power of the TRIGA Mark III reactor

    The design and implementation of an identification and control scheme of the TRIGA Mark III research nuclear reactor of the Instituto Nacional de Investigaciones Nucleares (ININ) of Mexico is presented in this thesis work. The identification of the reactor dynamics is carried out using fuzzy logic based systems, in which a learning process permits the adjustment of the membership function parameters by means of techniques based on neural networks and bio-inspired algorithms. The resulting identification system is a useful tool that allows the emulation of the reactor power behavior when different types of insertions of reactivity are applied into the core. The identification of the power can also be used for the tuning of the parameters of a control system. On the other hand, the regulation of the reactor power is carried out by means of an adaptive and stable fuzzy control scheme. The control law is derived using the input-output linearization technique, which permits the introduction of a desired power profile for the plant to follow asymptotically. This characteristic is suitable for managing the ascent of power from an initial level no up to a predetermined final level nf. During the increase of power, a constraint related to the rate of change in power is considered by the control scheme, thus minimizing the occurrence of a safety reactor shutdown due to a low reactor period value. Furthermore, the theory of stability in the sense of Lyapunov is used to obtain a supervisory control law which maintains the power error within a tolerance region, thus guaranteeing the stability of the power of the closed loop system. (Author)

  5. An Object Oriented Approach to Simulation of TRIGA Mark II Dynamic Response

    Bigoni, A.; Cammi, A.; Ponciroli, R. [Politecnico di Milano, Department of Energy, Nuclear Engineering Division (CeSNEF) Via Ponzio 34/3, 20133 Milano (Italy); Tigliole, A. Borio Di [University of Pavia, Department of Nuclear and Theoretical Physics and Laboratory of Applied Nuclear Energy (L.E.N.A), Via Bassi 4, 27100 Pavia (Italy)

    2011-07-01

    This paper deals with the development of a model for the nuclear research reactor TRIGA Mark II operating at University of Pavia. The purpose of the modeling is to reproduce the dynamic behavior of the reactor on the entire operative power range, i.e. 0-250 kW, using the object oriented approach, implemented by the Modelica language. The main advantage is the a-causal formulation of the model, based on equations instead of statement assignment. Equations do not specify which variables are inputs and which are outputs, thus the causality in the model is unspecified and is fixed only when the corresponding equation system is solved. In this way, equations can be solved according to the data flow context in which the solution is computed. The model describes the entire plant, including the heat removal system. The component representing the reactor core contains a series of sub-components linked together through rigorously defined interfaces: in this way, it is possible to consider the interactions between the different physical aspects of the system. Equations governing natural circulation have been implemented in a component which defines the mass flow rate through the core, according to the temperature difference at the ends of the channels. Secondary and tertiary cooling loops are modeled using a simplified heat exchangers configuration: concentric tube version is adopted, which allows recreating the heat exchange dynamics without a great modeling effort. The developed a-causal model has been validated through the comparison with experimental data collected on the site, concerning three different power transients at 100 kW, 50 kW and 1 kW. A corresponding causal model has been referenced as concerns fuel and coolant temperatures evolution during the transients. The predictions of the two main approaches to dynamic modeling have been compared. A very satisfying accordance is found as discrepancies observed on the coolant temperature are comprised between 0.5% and 1

  6. Licensing of the TRIGA Mark III reactor at the Mexican Nuclear Centre

    The TRIGA Mark III reactor at the Mexican Nuclear Centre went critical in 1968 and remained so until 1979 when the National Commission for Nuclear Safety and Safeguards (CNSNS), the Mexican regulatory authority, was set up. The reactor was therefore operating without a formal operating license, and the CNSNS accordingly requested the ININ to license the reactor under the existing conditions and to ensure that any modification of the original design complied with Standards ANSI/ANS-15 and with the code of practice set out in IAEA Safety Series No. 35. The most relevant points in granting the operating licence were: (a) the preparation of the Safety Report; (b) the formulation and application of the Quality Assurance Programme; (c) the reconditioning of the following reactor systems: the cooling systems; the ventilation and exhaust system; the monitoring system and control panel; (d) the training of the reactor operating staff at junior and senior levels; and (e) the formulation of procedures and instructions. Once the provisional operating license was obtained for the reactor it was considered necessary to modify the reactor core, which has been composed of 20% enriched standards fuel, to a mixed core based on a mixture of standard fuel and FLIP-type fuel with 70% 235U enrichment. The CNSNS therefore requested that the mixed core be licensed and a technical report was accordingly annexed to the Safety Report, its contents including the following subjects: (a) neutron analysis of the proposed configuration; (b) reactor shutdown margins; (c) accident analysis; and (d) technical specifications. The licensing process was completed this year and we are now hoping to obtain the final operating license

  7. An Object Oriented Approach to Simulation of TRIGA Mark II Dynamic Response

    This paper deals with the development of a model for the nuclear research reactor TRIGA Mark II operating at University of Pavia. The purpose of the modeling is to reproduce the dynamic behavior of the reactor on the entire operative power range, i.e. 0-250 kW, using the object oriented approach, implemented by the Modelica language. The main advantage is the a-causal formulation of the model, based on equations instead of statement assignment. Equations do not specify which variables are inputs and which are outputs, thus the causality in the model is unspecified and is fixed only when the corresponding equation system is solved. In this way, equations can be solved according to the data flow context in which the solution is computed. The model describes the entire plant, including the heat removal system. The component representing the reactor core contains a series of sub-components linked together through rigorously defined interfaces: in this way, it is possible to consider the interactions between the different physical aspects of the system. Equations governing natural circulation have been implemented in a component which defines the mass flow rate through the core, according to the temperature difference at the ends of the channels. Secondary and tertiary cooling loops are modeled using a simplified heat exchangers configuration: concentric tube version is adopted, which allows recreating the heat exchange dynamics without a great modeling effort. The developed a-causal model has been validated through the comparison with experimental data collected on the site, concerning three different power transients at 100 kW, 50 kW and 1 kW. A corresponding causal model has been referenced as concerns fuel and coolant temperatures evolution during the transients. The predictions of the two main approaches to dynamic modeling have been compared. A very satisfying accordance is found as discrepancies observed on the coolant temperature are comprised between 0.5% and 1

  8. Analysis of tritium production in TRIGA Mark II reactor at JSI for the needs of fusion research reactors

    Jazbec, Anze; Zerovnik, Gasper; Snoj, Luka; Trkov, Andrej [Jozef Stefan Institute, Ljubljana (Slovenia)

    2013-12-15

    In future, electricity could be produced in fusion power plants. One of the steps towards development of fusion power plants is the construction of an experimental fusion reactor ITER where deuterium (D) and tritium (T) will be fused and energy will be released. As natural concentrations of T are extremely low, the T as fusion fuel will have to be produced artificially. A series of calculations were made to investigate the possibility of producing small quantities of T for experimental fusion reactors such as JET and ITER in a small research reactor like the TRIGA Mark II reactor at the Jozef Stefan Institute (JSI). The T production is the largest if all irradiation channels in reactor's reflector are filled with LiAlO{sub 2} samples. When samples are inserted, the excess reactivity decreases by around 200 pcm. In the second part of the work an estimate was made of how long the reactor can operate with current fuel supplies. Calculations were made with the TRIGLAV computer code. TRIGA can operate at full power for at least 2,860 days, during which 152 mg of T could be produced. We conclude that small TRIGA reactors can not produce any significant quantities of T for the needs of the future experimental fusion reactors. (orig.)

  9. Analysis of tritium production in TRIGA Mark II reactor at JSI for the needs of fusion research reactors

    In future, electricity could be produced in fusion power plants. One of the steps towards development of fusion power plants is the construction of an experimental fusion reactor ITER where deuterium (D) and tritium (T) will be fused and energy will be released. As natural concentrations of T are extremely low, the T as fusion fuel will have to be produced artificially. A series of calculations were made to investigate the possibility of producing small quantities of T for experimental fusion reactors such as JET and ITER in a small research reactor like the TRIGA Mark II reactor at the Jozef Stefan Institute (JSI). The T production is the largest if all irradiation channels in reactor's reflector are filled with LiAlO2 samples. When samples are inserted, the excess reactivity decreases by around 200 pcm. In the second part of the work an estimate was made of how long the reactor can operate with current fuel supplies. Calculations were made with the TRIGLAV computer code. TRIGA can operate at full power for at least 2,860 days, during which 152 mg of T could be produced. We conclude that small TRIGA reactors can not produce any significant quantities of T for the needs of the future experimental fusion reactors. (orig.)

  10. Validation of WIMS-SNAP code systems for calculations in TRIGA-MARK II type reactors

    The following paper contributes to validate the Nuclear Engineering Department methods to carry out calculations in TRIGA reactors solving a Benchmark. The benchmark is analyzed with the WIMS-D/4-SNAP/3D code system and using the cross section library WIMS-TRIGA. A brief description of the DSN method is presented used in WIMS/d4 code and also the SNAP-3d code is shortly explained. The results are presented and compared with the experimental values. In other hand the possible error sources are analyzed. (author)