CONRAD Evaluation Code: Development Status and Perspectives

Archier, P.; Jean, C. De Saint; Litaize, O.; Noguère, G.; Berge, L.; Privas, Edwin; Tamagno, Pierre

doi:10.1016/j.nds.2014.04.114

Cited by 58 publications

(49 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1. FY covariance matrices have been evaluated using a e-mail: nicholas.terranova@unibo.it the CONRAD code [8]. The same independent FY semiempirical models used in JEFF-3.1.1 evaluations to fill the gaps existing in the available experimental measurements were employed and implemented in CONRAD.…”

Section: Covariance Generationmentioning

confidence: 99%

Covariance generation and uncertainty propagation for thermal and fast neutron induced fission yields

et al. 2017

View full text Add to dashboard Cite

Abstract. Fission product yields (FY) are fundamental nuclear data for several applications, including decay heat, shielding, dosimetry, burn-up calculations. To be safe and sustainable, modern and future nuclear systems require accurate knowledge on reactor parameters, with reduced margins of uncertainty. Present nuclear data libraries for FY do not provide consistent and complete uncertainty information which are limited, in many cases, to only variances. In the present work we propose a methodology to evaluate covariance matrices for thermal and fast neutron induced fission yields. The semi-empirical models adopted to evaluate the JEFF-3.1.1 FY library have been used in the Generalized Least Square Method available in CONRAD (COde for Nuclear Reaction Analysis and Data assimilation) to generate covariance matrices for several fissioning systems such as the thermal fission of U235, Pu239 and Pu241 and the fast fission of U238, Pu239 and Pu240. The impact of such covariances on nuclear applications has been estimated using deterministic and Monte Carlo uncertainty propagation techniques. We studied the effects on decay heat and reactivity loss uncertainty estimation for simplified test case geometries, such as PWR and SFR pin-cells. The impact on existing nuclear reactors, such as the Jules Horowitz Reactor under construction at CEA-Cadarache, has also been considered.

show abstract

Section: Covariance Generationmentioning

confidence: 99%

Covariance generation and uncertainty propagation for thermal and fast neutron induced fission yields

et al. 2017

View full text Add to dashboard Cite

show abstract

“…In the present work, a systematic study is reported as a function of the degree of the polynomial (n = 1, 2, 3). The fitting algorithm of the CONRAD code was used [36]. A Chi-square test provides a measure of the goodness-of-fit.…”

Section: Reactivity Excess As a Function Of Temperaturementioning

confidence: 99%

Impact of the thermal scattering law of H in H₂O on the isothermal temperature reactivity coefficients for UOX and MOX fuel lattices in cold operating conditions

Scotta

Noguère

Bernard

et al. 2016

EPJ Nuclear Sci. Technol.

View full text Add to dashboard Cite

Abstract. The contribution of the thermal scattering law of hydrogen in light water to isothermal temperature reactivity coefficients for UOX and MOX lattices was studied in the frame of the MISTRAL critical experiments carried out in the zero power reactor EOLE of CEA Cadarache (France). The interpretation of the core residual reactivity measured between 6°C to 80°C (by step of 5°C) was performed with the Monte-Carlo code TRIPOLI4 ® . The nuclear data from the JEFF-3.1.1 library were used in the calculations. Three different thermal scattering laws of hydrogen in light water were tested in order to evaluate their impact on the MISTRAL calculations. The thermal scattering laws of interest were firstly those recommended in JEFF-3.1.1 and ENDF/B-VII.1 and also that recently produced at the atomic center of Bariloche (CAB, Argentina) with molecular dynamic simulations. The present work indicates that the calculation-to-experimental bias is À0.4 ± 0.3 pcm/°C in the UOX core and À1.0 ± 0.3 pcm/°C in the MOX cores, when the JEFF-3.1.1 library is used. An improvement is observed over the whole temperature range with the CAB model. The calculation-to-experimental bias vanishes for the UOX core (À0.02 pcm/°C) and becomes close to À0.7 pcm/°C for the MOX cores. The magnitude of these bias have to be connected to the typical value of the temperature reactivity coefficient that ranges from À5 pcm/°C at Begining Of Cycle (BOC) up to À50 pcm/°C at End Of Cycle (EOC), in PWR conditions.

show abstract

“…It should be pointed out that no RP covariance data were derived at the time the evaluation was done. Other fitting codes such as REFIT [7,8] and CONRAD [9] may be used in the 16 O cross section evaluation up to 6 MeV as long as charged-particle penetrability can be calculated.…”

Section: Introductionmentioning

confidence: 99%

Resonance parameter and covariance evaluation for¹⁶O up to 6 MeV

Leal¹,

Ivanov²,

Noguère³

et al. 2016

EPJ Nuclear Sci. Technol.

View full text Add to dashboard Cite

Abstract. A resolved resonance evaluation was performed for 16 O in the energy range 0 eV to 6 MeV using the computer code SAMMY resulting in a set of resonance parameters (RPs) that describes well the experimental data used in the evaluation. A RP covariance matrix (RPC) was also generated. The RP were converted to the evaluated nuclear data file format using the R-Matrix Limited format and the compact format was used to represent the RPC. In contrast to the customary use of RP, which are frequently intended for the generation of total, capture, and scattering cross sections only, the present RP evaluation permits the computation of angle dependent cross sections. Furthermore, the RPs are capable of representing the (n, a) cross section from the energy threshold (2.354 MeV) of the (n, a) reaction to 6 MeV. The intent of this paper is to describe the procedures used in the evaluation of the RP and RPC, the use of the RPC in benchmark calculations and to assess the impact of the 16 O nuclear data uncertainties in the calculate dk eff for critical benchmark experiments.

show abstract

CONRAD Evaluation Code: Development Status and Perspectives

Cited by 58 publications

References 0 publications

Covariance generation and uncertainty propagation for thermal and fast neutron induced fission yields

Covariance generation and uncertainty propagation for thermal and fast neutron induced fission yields

Impact of the thermal scattering law of H in H₂O on the isothermal temperature reactivity coefficients for UOX and MOX fuel lattices in cold operating conditions

Resonance parameter and covariance evaluation for¹⁶O up to 6 MeV

Contact Info

Product

Resources

About

CONRAD Evaluation Code: Development Status and Perspectives

Cited by 58 publications

References 0 publications

Covariance generation and uncertainty propagation for thermal and fast neutron induced fission yields

Covariance generation and uncertainty propagation for thermal and fast neutron induced fission yields

Impact of the thermal scattering law of H in H2O on the isothermal temperature reactivity coefficients for UOX and MOX fuel lattices in cold operating conditions

Resonance parameter and covariance evaluation for16O up to 6 MeV

Contact Info

Product

Resources

About

Impact of the thermal scattering law of H in H₂O on the isothermal temperature reactivity coefficients for UOX and MOX fuel lattices in cold operating conditions

Resonance parameter and covariance evaluation for¹⁶O up to 6 MeV