ALFREDO YUUITIRO ABE
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Artigo IPEN-doc 27926 Modification of fuel performance code to evaluate iron-based alloy behavior under LOCA scenario2021 - GIOVEDI, C.; ABE, A.; MUNIZ, R.O.R.; GOMES, D.S.; SILVA, A.T.; MARTINS, M.R.Accident tolerant fuels (ATF) has been studied since the Fukushima Daiichi accident in the research efforts to develop new materials which under accident scenarios could maintain the fuel rod integrity for a longer period compared to the cladding and fuel system usually utilized in Pressurized Water Reactors (PWR). The efforts have been focused on new materials applied as cladding, then iron-base alloys appear as a possible candidate. The aim of this paper is to implement modifications in FRAPCON and FRAPTRAN fuel performance codes to evaluate the behavior of iron-based alloys under Loss-of-Coolant Accident (LOCA) scenario. For this, initially the properties related to the thermal and mechanical behavior of iron-based alloys were obtained from the literature, appropriately adapted and introduced in the fuel performance code subroutines. The adopted approach was step by step modifications, where different versions of the code were created. The assessment of the implemented modification was carried out simulating an experiment available in the open literature (IFA-650.5) related to zirconium-based alloy fuel rods submitted to LOCA conditions. The obtained results for the iron-based alloy were compared to those obtained using the regular version of the fuel performance code for zircaloy-4. The obtained results have shown that the most important properties to be changed are those from the subroutines related to the mechanical properties of the cladding. The results obtained have shown that the burst is observed at a longer time for fuel rods with iron-based alloy, indicating the potentiality of this material to be used as cladding with ATF purposes.Capítulo IPEN-doc 27693 Neutronic screening of potential candidate for accident tolerant fuel2020 - ABE, ALFREDO; GIOVEDI, CLAUDIA; MARTINS, M.Capítulo IPEN-doc 27691 Preliminary neutronic assessment of iron based alloy fuel cladding2020 - ABE, ALFREDO; CARLUCCIO, THIAGO; PIOVEZAN, PAMELA; GIOVEDI, CLAUDIA; MARTINS, MARCELO R.Nowadays two important nuclear fuel performance requirements have been addressed: high burnup in order to improve fuel cycle economic aspect and accident tolerant fuel to enhance the safety under accident condition. The accident tolerant fuel particularly becomes very important issue after Fukushima Daiichi nuclear accident in 2011. The initiatives of R&D program toward to accident tolerant fuel comprises different countries, organizations and including fuel vendors. The Accident Tolerant Fuel (ATF) can be defined as enhanced fuel which can tolerate loss of active cooling system capability for a considerably longer time period and the fuel/cladding system can be maintained without significant degradation and can also improve the fuel performance during normal operations and transients, as well as design-basis accident (DBA) and beyond design-basis (BDBA) accident. Different materials have been proposed as fuel cladding candidates considering thermo-mechanical properties and lower reaction kinetic with steam and slower hydrogen production, besides that an evaluation of the neutronic aspects for several cladding candidates is important and shall be evaluated. Depending of the outcome of this evaluation, the fuel enrichment level changes to higher than actual level shall be necessary to overcome the neutron absorption penalty. The aim of this work is to perform a preliminary neutronic assessment of fuel cladding based on iron alloy considering a standard PWR fuel rod (fuel pellet and dimension). The main purpose of the assessment is to quantify the penalty due to increase of neutron absorption in the cladding materials and some others fuel parameters are evaluated in order to overcome such penalty. In addition to neutronic assessment, the criticality safety aspects due to increase of fuel enrichment level are briefly presented and discussed.Artigo IPEN-doc 26855 Reactivity initiated accident assessment for ATF cladding materials2020 - GIOVEDI, C.; MARTINS, M.R.; ABE, A.; REIS, R.; SILVA, A.T.Following the experience that came from the Fukushima Daiichi accident, one possible way of reducing risk in a nuclear power plant operation would be the replacement of the existing fuel rod cladding material (based on zirconium alloys) by another materials which could fulfill the requirements of the accident tolerant fuel (ATF) concept. In this sense, ATF should be able to keep the current fuel system performance under normal operation conditions; moreover, it should present superior performance than the existing conventional fuel system (zirconium-based alloys and uranium dioxide) under accident conditions. The most challenging and bounding accident scenarios for nuclear fuel systems in Pressurized Water Reactors (PWR) are Loss of Coolant Accident (LOCA) and Reactivity Initiated Accident (RIA), which are postulated accidents. This work addresses the performance of ATF using iron-based alloys as cladding material under RIA conditions. The evaluation is carried out using modified versions of the coupled system FRAPCON/FRAPTRAN. These codes were modified to include the material properties (thermal, mechanical, and physics) of an iron-based alloy, specifically FeCrAl alloy. The analysis is performed using data available in the open literature related to experiments using conventional PWR fuel system (zirconium-based alloys and uranium dioxide). The results obtained using the modified code versions are compared to those of the actual existing fuel system based on zircaloy-4 cladding using the original versions of the fuel performance codes (FRAPCON/FRAPTRAN).Artigo IPEN-doc 26356 Fuel performance of iron-based alloy cladding using modified TRANSURANUS code2019 - GIOVEDI, CLAUDIA; MELO, CAIO; ABE, ALFREDO Y.; SILVA, ANTONIO T.; MARTINS, MARCELO R.The main challenge in the nuclear area since the Fukushima Daiichi accident is to develop fuel materials to be applied in nuclear reactors aiming to increase the safety under normal operation as well as transient and accident conditions. These efforts are concentrated in the Advanced Technology Fuel (ATF) program that has as main scopes to study cladding materials to replace the zirconium-based alloys, and fuel materials presenting higher thermal conductivity compared to the conventional uranium dioxide fuel pellet. In this sense, iron-based alloys, which were used with a good performance as cladding material in the first Pressurized Water Reactors (PWR), have becoming a good option. The assessment of the behavior of different materials previously to perform irradiation tests, which are time consuming, can be performed using fuel performance codes, but for this, the conventional fuel performance codes must be modified to implement the properties of the materials that are being studied. This paper presents the results obtained using a modified version of the well-known TRANSURANUS code, obtained from the implementation of the stainless steel 348 properties as cladding material. The simulations were performed using data available in the open literature related to a PWR irradiation experiment. The results obtained using the modified version of the code were compared to those obtained using the original code version for zircaloy-4. The performance of both cladding materials was evaluated by means of the comparison of parameters such as gap thickness, fuel centerline temperature, internal pressure, and cladding stress and strain.Artigo IPEN-doc 24012 Modification of fuel performance code to evaluate iron-based alloy behavior under loca scenario2017 - GIOVEDI, CLAUDIA; ABE, ALFREDO; MUNIZ, RAFAEL O.R.; GOMES, DANIEL de S.; SILVA, ANTONIO T. e; MARTINS, MARCELO R.Accident tolerant fuels (ATF) has been studied since the Fukushima Daiichi accident in the research efforts to develop new materials which under accident scenarios could maintain the fuel rod integrity for a longer period compared to the cladding and fuel system usually utilized in Pressurized Water Reactors (PWR). The efforts have been focused on new materials applied as cladding, then iron-base alloys appear as a possible candidate. The aim of this paper is to implement modifications in a fuel performance code to evaluate the behavior of ironbased alloys under Loss-of-Coolant Accident (LOCA) scenario. For this, initially the properties related to the thermal and mechanical behavior of iron-based alloys were obtained from the literature, appropriately adapted and introduced in the fuel performance code subroutines. The adopted approach was step by step modifications, where different versions of the code were created. The assessment of the implemented modification was carried out simulating an experiment available in the open literature (IFA-650.5) related to zirconium-based alloy fuel rods submitted to LOCA conditions. The obtained results for the iron-based alloy were compared to those obtained using the regular version of the fuel performance code for zircaloy-4. The obtained results have shown that the most important properties to be changed are those from the subroutines related to the mechanical properties of the cladding. The results obtained have shown that the burst is observed at a longer time for fuel rods with iron-based alloy, indicating the potentiality of this material to be used as cladding with ATF purposes.Artigo IPEN-doc 24011 Assessment of uranium dioxide fuel performance with the addition of beryllium oxide2017 - MUNIZ, RAFAEL O.R.; GIOVEDI, CLAUDIA; ABE, ALFREDO; GOMES, DANIEL S.; AGUIAR, AMANDA A.; SILVA, ANTONIO T.The Fukushima Daiichi accident in 2011 pointed the problem related to the hydrogen generation under accident scenarios due to the oxidation of zirconium-based alloys widely used as fuel rod cladding in water-cooled reactors. This problem promoted research programs aiming the development of accident tolerant fuels (ATF) which are fuels that under accident conditions could keep longer its integrity enabling the mitigation of the accident effects. In the framework of the ATF program, different materials have been studied to be applied as cladding to replace zirconium-based alloy; also efforts have been made to improve the uranium dioxide thermal conductivity doping the fuel pellet. This paper evaluates the addition of beryllium oxide (BeO) to the uranium dioxide in order to enhance the thermal conductivity of the fuel pellet. Investigations performed in this area considering the addition of 10% in volume of BeO, resulting in the UO2-BeO fuel, have shown good results with the improvement of the fuel thermal conductivity and the consequent reduction of the fuel temperatures under irradiation. In this paper, two models obtained from open literature for the thermal conductivity of UO2- BeO fuel were implemented in the FRAPCON 3.5 code and the results obtained using the modified code versions were compared. The simulations were carried out using a case available in the code documentation related to a typical pressurized water reactor (PWR) fuel rod irradiated under steady state condition. The results show that the fuel centerline temperatures decrease with the addition of BeO, when compared to the conventional UO2 pellet, independent of the model applied.Artigo IPEN-doc 23518 Evaluation of corrosion on the fuel performance of stainless steel cladding2016 - GOMES, DANIEL de S.; ABE, ALFREDO; SILVA, ANTONIO T. e; GIOVEDI, CLAUDIA; MARTINS, MARCELO R.In nuclear reactors, the use of stainless steel (SS) as the cladding material offers some advantages such as good mechanical and corrosion resistance. However, its main advantage is the reduction in the amount of the hydrogen released during loss-of-coolant accident, as observed in the Fukushima Daiichi accident. Hence, research aimed at developing accident tolerant fuels should consider SS as an important alternative to existing materials. However, the available computational tools used to analyze fuel rod performance under irradiation are not capable of assessing the effectiveness of SS as the cladding material. This paper addresses the SS corrosion behavior in a modified fuel performance code in order to evaluate its effect on the global fuel performance. Then, data from the literature concerning to SS corrosion are implemented in the specific code subroutines, and the results obtained are compared to those for Zircaloy-4 (Zy-4) under the same power history. The results show that the effects of corrosion on SS are considerably different from those on Zy-4. The thickness of the oxide layer formed on the SS surface is considerably lower than that formed on Zy-4. As a consequence of this, the global fuel performance of SS under irradiation should be less affected by the corrosion.Artigo IPEN-doc 21150 The quest for safe and reliable fuel cladding materials2015 - PINO, EDDY S.; ABE, ALFREDO Y.; GIOVEDI, CLAUDIAArtigo IPEN-doc 21070 Preliminary neutronic assessmento for ATF (Accident Tolerant Fuel) based on iron alloy2015 - ABE, ALFREDO; CARLUCCIO, THIAGO; PIOVEZAN, PAMELA; GIOVEDI, CLAUDIA; MARTINS, MARCELO