The case for extended nuclear reactor operation

Traveling wave reactor is a kind of nuclear reactor that can convert fertile material into fissile fuel as it runs using the process of nuclear transmutation. In the ignition stage of traveling wave reactor, the core performance is especially complex, since the fissile fuel and fertile material is put in different regions at the beginning. And the distribution of power density will change severely with burn-up during the reactor operation. It is an important part of the traveling wave reactor study to optimize the design of the ignition stage. In this paper, based on a two-dimensional RZ geometry model, some schemes with different sizes and compositions of the ignition zone, middle ignition zone position design and burnable neutron poison addition are simulated and analyzed. Finally, an optimized core design with multi-zone configuration and burnable neutron poison addition is shown. Some design outlines are introduced for further study.

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Thermal Transport in Actinide Oxide Fuels With Interstitial Defects

Volume 6: Energy ◽

10.1115/imece2019-11027 ◽

2019 ◽

Author(s):

Katherine Mitchell ◽

Hunter Horner ◽

Alex Resnick ◽

Jungkyu Park ◽

Eduardo B. Farfán ◽

...

Keyword(s):

Point Defects ◽

Thermal Transport ◽

Nuclear Reactor ◽

Nuclear Reactors ◽

Reactor Operation ◽

Oxygen Interstitial ◽

Interstitial Defects ◽

Actinide Oxides ◽

Non Equilibrium Molecular Dynamics ◽

Thermal Conductivities

Abstract Molecular displacement occurs in the oxide fuels of nuclear reactors during operation. This causes several types of point defects to be generated inside the oxide nuclear fuels. To improve the safety and efficiency of nuclear reactor operation, it is necessary to better understand the effects of point defects on the properties of the oxide fuels. In this study, we examine the effects of interstitial defects on thermal transport in two representative actinide oxides used in modern reactors (UO2, and PuO2). Reverse non-equilibrium molecular dynamics (RNEMD) is employed to approximate the thermal conductivities for the aforementioned fuels at several sample lengths and at defect concentrations of 0.1%, 1%, and 5%. The results show that alterations to the lattice structures of these fuels reduce their thermal conductivities significantly. For example, oxygen interstitial defects at concentrations even as low as 0.1% decreased thermal conductivity by 20% at 100 units for each fuel.

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A New Safety Principle For The Slowpoke Reactor

AECL Nuclear Review ◽

10.12943/anr.2013.00011 ◽

2013 ◽

Vol 2 (1) ◽

pp. 113-118 ◽

Cited By ~ 1

Author(s):

S. Yue ◽

S. Polugari ◽

V. Anghel ◽

J. Hilborn ◽

B. Sur

Keyword(s):

Nuclear Reactor ◽

Thermal Power ◽

Reactor Operation ◽

Simulink Model ◽

Negative Reactivity ◽

Full Power ◽

Safety Features ◽

Pool Type ◽

High Neutron ◽

High Neutron Flux

SLOWPOKE-2 (LEU core) is a pool-type nuclear reactor with a maximum nominal thermal power of 20 kW. It uses a pelletized uranium oxide fuel (19.9% enrichment) and provides a useful high neutron flux in the order of 1012 n.cm2s-1. The key safety features built into the reactor design are the strictly limited amount of excess reactivity and the negative reactivity feedback characteristics, which provide a demonstrably safe self-limiting power excursion response to large reactivity insertions. However, the limited amount of excess reactivity also limits continuous prolonged reactor operation at full power. With a 4 mk excess reactivity, the reactor can operate for about one day at full power, 20 kW, before criticality is lost due to temperature effects and xenon poisoning. A new safety concept is proposed in this paper that enables the continuous operation to a few months by increasing the excess reactivity from 4 mk to 8 mk. A Matlab/simulink model of SLOWPOKE-2 has demonstrated that core operation life can be extended to several months without adding a beryllium shim.

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An Effect of Nuclear-reactor Operation in Space

Nature ◽

10.1038/209064a0 ◽

1966 ◽

Vol 209 (5018) ◽

pp. 64-64 ◽

Cited By ~ 1

Author(s):

DONALD G. CARPENTER ◽

RICHARD E. DENFELD ◽

KENNETH H. KRONLUND

Keyword(s):

Nuclear Reactor ◽

Reactor Operation

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Creation of Interface System for Nuclear Reactor Operation

Proceedings of the Human Factors and Ergonomics Society Annual Meeting ◽

10.1177/154193120004402220 ◽

2000 ◽

Vol 44 (22) ◽

pp. 571-574 ◽

Cited By ~ 10

Author(s):

Yukichi Yamaguchi ◽

Fumiya Tanabe

Keyword(s):

Nuclear Reactor ◽

Empirical Evaluation ◽

System Structure ◽

Complex Nature ◽

Graphical Display ◽

Reactor Operation ◽

Research Project ◽

Interface System ◽

Operation Procedure ◽

System Verification

Present status of on going JAERI's research project aiming at empirical evaluation of the EID concept is described. The research project is proceeded with three consecutive steps: design and implementation of the interface system, verification, and validation of the interface on a full-scope reactor simulator. Following detailed analysis of system structure in a way of “walking-through” the operation procedure on the simulator, a new interface system was created on this. In the newly created interface system, sets of graphical display formats representing higher levels of information items and new navigation mechanism were introduced to cope with complex nature of reactor system. At present, verification work for this new interface system is being conducted.

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THE ASSESSMENT OF BANDUNG TRIGA REACTOR TANK RADIOACTIVITY IN THE PERIOD 2000-2014 USING ORIGEN-2

Jurnal Sains dan Teknologi Nuklir Indonesia ◽

10.17146/jstni.2017.18.2.3622 ◽

2017 ◽

Vol 18 (2) ◽

pp. 109

Author(s):

Sudjatmi Kustituantini Alfa ◽

Reinaldy Nazar ◽

Ketut Kamajaya ◽

Putranto Ilham Y

Keyword(s):

Aluminum Alloy ◽

Nuclear Reactor ◽

Research Reactor ◽

Total Radioactivity ◽

Regulatory Body ◽

Reactor Operation ◽

Triga Reactor ◽

Aluminum Alloy 6061 ◽

Year 2000 ◽

Alloy 6061

THE ASSESSMENT OF BANDUNG TRIGA REACTOR TANK RADIOACTIVITY IN THE PERIOD 2000-2014 USING ORIGEN-2 In accordance with the regulation of the regulatory body of Indonesia related to the decommissioning of nuclear reactors, the management of the Bandung TRIGA reactor have to prepare a decommissioning plan document of the Bandung TRIGA research reactor. Decommissioning program documents shall be regularly updated every five years of the operation of nuclear reactor. In year 2000, Bandung TRIGA reactor tank have been lined using aluminum alloy 6061-T6 and has activated during reactor operation. Aluminum alloy 6061-T6 contains impurities that can produce high radioactivity and has a long half-life. This paper describes the radioactivity of the reactor tank after activation during the period from 2000 to 2014 using the software ORIGEN-2. Total radioactivity of the reactor tank bottom after decay for 5 years was 1.83 10-7 Curie, while the total radioactivity of reactor tank wall was 3.2 10-3 Curie.

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