Determination of the Thermohydraulic Parameters of Inter-Fuel-Element Channels in Research Reactors with Four-Bladed Fuel Elements

The paper deals with experimental data regarding the effect of internal and external factors on the corrosion decay of Zr1Nb alloy fuel elements. Based on the analysis results, losses of zirconium that transfers to oxide or coolant as per the fuel element wall weight and thickness as well as economic losses from their corrosion decay have been theoretically calculated. To avoid a state-level emergency occurrence, an increase in the fuel element wall thickness up to 660 μm is proposed, which can increase the operating life under the conditions of trouble-free coolant mass transfer hydrodynamic mode.

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Study on Temperature Distribution of Pebble-Bed HTR Fuel Element by Using Boundary Element Method

Volume 6B: Materials and Fabrication ◽

10.1115/pvp2013-97454 ◽

2013 ◽

Author(s):

Haitao Wang ◽

Xin Wang

Keyword(s):

Fuel Element ◽

Boundary Element ◽

Large Scale ◽

Maximum Temperature ◽

Element Formulation ◽

Desktop Computer ◽

Pebble Bed ◽

Graphite Matrix ◽

Fuel Particles ◽

Fuel Elements

Spherical fuel elements with a diameter of 60mm are basic units of the nuclear fuel for the pebble-bed high temperature gas-cooled reactor (HTR). Each fuel element is treated as a graphite matrix containing around 10,000 randomly distributed fuel particles. The essential safety concept of the pebble-bed HTR is based on the objective that maximum temperature of the fuel particles does not exceed the design value. In this paper, a microstructure-based boundary element model is proposed for the large-scale thermal analysis of a spherical fuel element. This model presents detailed structural information of a large number of coated fuel particles dispersed in a spherical graphite matrix in order that temperature distributions at the level of fuel particles can be evaluated. The model is meshed with boundary elements in conjunction with the fast multipole method (FMM) in order that such large-scale computation is performed only in a personal desktop computer. Taking advantage of the fact that fuel particles are of the same shape, a similar sub-domain approach is used to establish the temperature translation mechanism between various layers of each fuel particle and to simplify the associated boundary element formulation. The numerical results demonstrate large-scale capacity of the proposed method for the multi-level temperature evaluation of the pebble-bed HTR fuel elements.

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Studies on Production Planning of Dispersion Type U<sub>3</sub>Si<sub>2</sub>-Al Fuel in Plate-Type Fuel Elements for Nuclear Research Reactors

World Journal of Nuclear Science and Technology ◽

10.4236/wjnst.2016.64023 ◽

2016 ◽

Vol 06 (04) ◽

pp. 217-231

Author(s):

Miguel Luiz Miotto Negro ◽

Michelangelo Durazzo ◽

Marco Aurélio de Mesquita ◽

Elita Fontenele Urano de Carvalho ◽

Delvonei Alves de Andrade

Keyword(s):

Production Planning ◽

Nuclear Research ◽

Research Reactors ◽

Fuel Elements ◽

Type Fuel ◽

Plate Type

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THE THERMOHYDRAULIC ANALYSIS OF THE BANDUNG RESEARCH REACTOR CORE WITH PLATE TYPE FUEL ELEMENTS USING THE CFD CODE

JURNAL TEKNOLOGI REAKTOR NUKLIR TRI DASA MEGA ◽

10.17146/tdm.2018.20.3.4626 ◽

2018 ◽

Vol 20 (3) ◽

pp. 123

Author(s):

Reinaldy Nazar ◽

Sudjatmi KA ◽

Ketut Kamajaya

Keyword(s):

Fuel Element ◽

Surface Temperature ◽

Forced Convection ◽

Flow Rate ◽

Research Reactor ◽

Saturation Temperature ◽

Cooling Flow ◽

Fuel Elements ◽

Type Fuel ◽

Plate Type

Due to TRIGA fuel elements are no longer produced by General Atomic, it is necessary to find a solution so that the Bandung TRIGA 2000 reactor can still be operated. One solution is to replace the type of fuel elements. Study on using the MTR plate type fuel elements as used in RSG-GAS Serpong has been done for the Bandung TRIGA 2000. Based on the results of the study using CFD computer program, it is found that Bandung TRIGA 2000 with plate type fuel elements cannot be operated up to 2000 kW power by natural convection cooling mode. Therefore, the reactor must be cooled by forced convection. The analysis using forced convection showed that for cooling flow rate of 50 kg/s and various temperatures of 35oC, 35.5 oC and 36 oC, the surface temperature of the fuel element is between 110.37 oC and 111.27 oC. Meanwhile, the cooling water temperature in the corresponding position is between 61.03 oC and 61.95 oC. In this operation condition, the surface temperatures of fuel elements can approach the saturation temperature and nucleat boiling started to occur. Hence, the use of cooling flow rate entering core less than 50 kg/s should be avoided. The surface temperature of fuel elements decreased under saturation temperature if cooling flow rate is greater than 65 kg/s. The surface temperature of fuel elements is achieved at 96.65 oC and coolant temperature in the corresponding position was 54.38 oC. Keywords: Bandung research reactor, plate type fuel element, thermohydraulic, CFD code ANALISIS TERMOHIDROLIK TERAS REAKTOR RISET BANDUNG BERELEMEN BAKAR TIPE PELAT MENGGUNAKAN PROGRAM CFD. Mengingat tidak diproduksinya lagi elemen bakar TRIGA oleh General Atomic, maka perlu diusahakan suatu solusi agar reaktor TRIGA 2000 Bandung dapat tetap beroperasi. Salah satu solusi adalah dengan melakukan penggantian tipe elemen bakar. Pada studi ini telah dianalisis penggunaan elemen bakar tipe pelat yang sejenis dengan yang digunakan di RSG-GAS Serpong, untuk digunakankan pada teras reaktor TRIGA 2000 Bandung. Berdasarkan hasil penelitian yang telah dilakukan dengan menggunakan program komputer CFD, diketahui bahwa reaktor TRIGA berelemen bakar tipe pelat tidak dapat dioperasikan pada daya 2000 kW dengan menggunakan moda pendinginan konveksi alamiah seperti yang digunakan saat ini. Untuk kondisi ini, pendinginan dilakukan dengan moda pendinginan konveksi paksa. Hasil analisis konveksi paksa menunjukkan bahwa dengan menggunakan laju alir pendingin pompa 50 kg/s dan variasi temperatur pada 35 oC, 35,5 oC dan 36 oC, diperoleh temperatur permukaan pelat elemen bakar antara 110,37 oC – 111,27 oC dan temperatur pendinginnya pada posisi terkait antara 61,03 oC – 61,95 oC. Temperatur permukaan pelat elemen bakar ini mendekati temperatur saturasi dan tentunya telah mulai terjadi pendidihan inti, sehingga penggunaan laju alir pendingin masuk teras reaktor kurang dari 50 kg/s perlu dihindari. Temperatur permukaan pelat elemen bakar mulai menurun menjauhi temperatur saturasi jika digunakan laju alir pendingin lebih besar dari 65 kg/s, dengan temperatur permukaan pelat elemen bakar 96,65 oC dan temperatur pendinginnya pada posisi terkait 54,38 oC.Kata kunci: Reaktor riset Bandung, elemen bakar tipe pelat, termohidrolik, program CFD

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Determination of Damage Functions for Polyatomic Materials Irradiated in Research Reactors

Reactor Dosimetry: Methods, Applications, and Standardization ◽

10.1520/stp10118s ◽

2008 ◽

pp. 576-576-16

Author(s):

A Alberman ◽

D Lesueur

Keyword(s):

Damage Functions ◽

Research Reactors

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Design of U3Si2-Al Plate-Type Fuel Element for China Advanced Research Reactor

18th International Conference on Nuclear Engineering: Volume 6 ◽

10.1115/icone18-29231 ◽

2010 ◽

Author(s):

Aimin Zhang ◽

Yalun Kang

Keyword(s):

Fuel Element ◽

Neutron Flux ◽

Research Reactor ◽

High Heat ◽

Reactor Power ◽

High Heat Flux ◽

Water Tank ◽

Enriched Uranium ◽

Fuel Elements ◽

Plate Type

China Advanced Research Reactor (CARR), which will be critical in China Institute of Atomic Energy (CIAE) in 2010, is a multipurpose, high neutron flux and tank-type (inverse neutron trap) reactor with compact core. Its nominal reactor power is 60MW and the maximum thermal neutron flux is about 8.0×1014n/cm2·s in heavy water tank. It has a cylindrical core having a diameter of about 450mm and a height of 850mm. The CARR’s core consists of seventeen plate-type standard fuel elements and four follower fuel elements, initially loaded with 10.97 kg of 235U. The fuel element has been designed with U3S2-Al dispersion containing 235U of (19.75±0.20)wt.% low enriched uranium (LEU) and having a density of 4.3gU/cm3. The aluminum alloy is used as the cladding. There are twenty-one and seventeen fuel plates in the standard and follower fuel element, respectively. There are specific requirements for design of the fuel element and strict limitation for the operation parameters due to the high heat flux and high velocity of coolant in CARR. Irradiation test of fuel element had been carried out at fuel element power of 3.1±20%MW at Russia MIR reactor. Average burnup of fuel element is up to 40%. This paper deals with the detailed design of fuel element for CARR, out-pile and in-pile test projects, including selection of fuel and structure material, description of element structure, miniplates and fuel element irradiation experiment, measurement of properties of fuel plate, fabrication of fuel element and test results.

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Paper 12: The Development of an Apparatus to Measure the Normal Emissivity of Small Plane Samples in a Controlled Atmosphere

Proceedings of the Institution of Mechanical Engineers Conference Proceedings ◽

10.1243/pime_conf_1967_182_222_02 ◽

1967 ◽

Vol 182 (8) ◽

pp. 120-129 ◽

Cited By ~ 1

Author(s):

B. N. Furber ◽

R. Broderick

Keyword(s):

Heat Transfer ◽

Carbon Dioxide ◽

Fuel Element ◽

Geometrical Factor ◽

Controlled Atmosphere ◽

Effective Emissivity ◽

General Application ◽

Safety Assessments ◽

Fuel Elements ◽

Normal Emissivity

The heat transfer from fuel elements in magnox reactors under all normal conditions is predominantly by forced convection. However, in safety assessments a burst in a bottom main coolant duct is postulated, a reversal of the carbon dioxide coolant flow takes place, and heat transfer from the fuel elements at this instant could be by radiation only. The effective emissivity of the fuel element or the normal emissivity of plane specimens of fuel element material and a geometrical factor are therefore required to enable the maximum fuel element temperature to be determined. The paper is mainly concerned with the development and calibration of an apparatus suitable for measuring the normal emissivity of small plane samples at temperatures up to 650°C. Though the design of the apparatus has been influenced by the special requirements involved in testing magnox specimens, the apparatus has a general application and the normal emissivities of other materials are also given.

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