The effects of fuel type on control rod reactivity of pebble-bed reactor

Zuhair,; Suwoto, Suwoto; Setiadipura, Topan; Kuijper, Jim C.

doi:10.2478/nuka-2019-0017

Cited by 14 publications

(5 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The structural components of the reactor core such as graphite reflectors were easily modeled while the coolant in the reflector side and especially, the reactor shutdown and control systems require special effort in modeling. The modeling and calculations performed in this study were demonstrated successfully in various publications [11][12][13][14][15][16][17][18][19][20][21][22].…”

Section: Pebbles In Core Modelingmentioning

confidence: 76%

Effects of Fuel Density on Reactivity Coefficients and Kinetic Parameters of Pebble Bed Reactor

Suwoto¹,

Dwijayanto²,

Luthfi³

et al. 2022

urania

View full text Add to dashboard Cite

EFFECTS OF FUEL DENSITY ON REACTIVITY COEFFICIENTS AND KINETIC PARAMETERS OF PEBBLE BED REACTOR. Few decades ago a large number of nuclear reactors were designed to use HEU as the fuel. But the use of HEU is being discouraged since it can be used as a nuclear explosive material which makes its proliferation potential. Most of the HEU-fueled nuclear reactors in the world are either closed or converted into other types that have LEU fuel with 235U enrichment below 20%. To extend lifetime, LEU fuel with high density is developed. The change in fuel density from low to high will also change core neutronics and thermal-hydraulics of the reactor, and as a result, it affects the transient response of the reactor. This paper studies the effects of fuel density on reactivity coefficients and kinetic parameters of pebble bed reactor through several calculations with MCNP6 code combine with ENDF/B-VII.1 continuous energy cross-section nuclear data library. The overall calculation results show that the Doppler temperature coefficient (DTC) increases with increasing fuel density, but the moderator temperature coefficient (MTC) decreases due to hardening of neutron spectrum. Kinetic parameters such as effective delayed neutron fraction (βeff), prompt neutron lifetime(ℓ) and neutron generation time (Ʌ) which significantly reduced with increasing fuel density will strongly affect the reactor control and safety. The results of this work conclude that the selection of 9–15 g/cm3 fuel density should be considered carefully given that its effect on reactor controllability.Keywords: Fuel density, reactivity coefficients, kinetic parameters, MCNP6, ENDF/B-VII.1.

show abstract

Section: Pebbles In Core Modelingmentioning

confidence: 76%

Effects of Fuel Density on Reactivity Coefficients and Kinetic Parameters of Pebble Bed Reactor

Suwoto¹,

Dwijayanto²,

Luthfi³

et al. 2022

urania

View full text Add to dashboard Cite

show abstract

“…To obtain these values, a neutronic simulation was performed using the MCNP6.2 radiation transport code with the ENDF/B-VII.0 neutron cross-section library. MCNP is a well-established code for simulating the neutronic aspects of nuclear reactors and has been extensively used for various types of reactors [25][26][27][28][29][30]. Although MCNP may not be the most suitable simulation tool for MSR due to its decoupling from thermal-hydraulic calculations, it has nonetheless been used for simulating various MSR designs, such as MSBR [6,31,32], MSR-FUJI [9], TMSR-500 [33][34][35], and Integral Molten Salt Reactor (IMSR) [36], with good agreement to the reference.…”

Section: Methodsmentioning

confidence: 99%

Neutronic Design Modification of Passive Compact-Molten Salt Reactor

Dwijayanto,

Harto

2024

Atom Indo.

View full text Add to dashboard Cite

Passive compact molten salt reactor (PCMSR) is a design concept of a molten salt reactor (MSR) currently under development in Universitas Gadjah Mada, Indonesia. It is designed as a thermal breeder reactor using thorium fuel cycle. However, our previous study shows that the original PCMSR design was incorrectly modelled, primarily overestimating its thorium breeding capability. To improve PCMSR neutronic design, we modified the core configuration by the addition of radial fuel channel layers previously nonexistent in original PCMSR core design in various configurations. Neutronic parameters of modified PCMSR geometries in the beginning of life (BOL) were simulated using MCNP6.2 radiation transport code with ENDF/B-VII.0 library. All variations of fuel layer addition show improvement in both temperature coefficient of reactivity (TCR) and breeding ratio (BR), with TCR values became more negative and BR values are larger than unity, ensuring proper breeding capability. Configuration Inner Core-Outer Blanket (IC-OB) achieves the largest BR and lowest doubling time (DT), whilst its TCR is an improvement from the original design. Therefore, IC-OB fuel layer configuration can be applied to redesign the original PCMSR and used in various design optimization scenarios.

show abstract

“…Core com po nents and struc tures, such as ax ial and ra dial re flec tors, etc., were mod eled in a sim pler way. A de tailed de scrip tion of this pro ce dure was first in troduced by Lebenhaft [19] and found in sev eral pub li cations [20][21][22][23][24][25][26][27][28]. The whole fa cil ity mod el ing of HTR-Proteus is il lus trated in fig.…”

Section: Cal Cu La Tion Modelmentioning

confidence: 99%

Study on kinetic parameters characteristics of pebble bed reactor using HTR-proteus facility

Zuhair¹,

Luthfi²,

Sriyono³

et al. 2022

NUCL TECH RAD PROT

Self Cite

View full text Add to dashboard Cite

The inherent safety feature of a pebble-bed reactor can be observed from its kinetic parameters. Proper modeling for calculating the reactor kinetic is also a concern for safe operation during normal and transient conditions. This study is intended to investigate the kinetic parameters characteristics of a pebble bed reactor using HTR-Proteus. A series of calculations were conducted using MCNP6 code and ENDF/B-VII library. The calculation results show that the negative value on core temperature reactivity is affected dominantly by the Doppler broadening effect. Prompt neutron lifetime l and mean generation time ? are slightly changed due to an increase in fuel temperature, moderator, and reflector that changed the neutron moderation and absorption over this part of the reactor. For (Th, U)O2, UO2, and PuO2 cores, the effective delayed neutron fraction ?eff values are more influenced by 233U, 235U, and 239Pu, respectively. In terms of stability during reactivity insertion, the UO 2 core is more stable and easier to control because its ?eff value is the largest compared to (Th,U)O2 and PuO 2 cores. It can be concluded that temperature must be controlled because it does not only affect the reactivity but also kinetic parameters as part of developing inherent safety features on the pebble-bed reactor.

show abstract

The effects of fuel type on control rod reactivity of pebble-bed reactor

Cited by 14 publications

References 12 publications

Effects of Fuel Density on Reactivity Coefficients and Kinetic Parameters of Pebble Bed Reactor

Effects of Fuel Density on Reactivity Coefficients and Kinetic Parameters of Pebble Bed Reactor

Neutronic Design Modification of Passive Compact-Molten Salt Reactor

Study on kinetic parameters characteristics of pebble bed reactor using HTR-proteus facility

Contact Info

Product

Resources

About