Analysis of the thermal-mechanical behavior of SFR fuel pins during fast unprotected transient overpower accidents using the GERMINAL fuel performance code

Dupont Vincent,Blanc Victor,Beck Thierry,Lainet Marc,Sciora Pierre 한국원자력학회 2024 Nuclear Engineering and Technology Vol.56 No.3

In the framework of the Generation IV research and development project, in which the French Commission of Alternative and Atomic Energies (CEA) is involved, a main objective for the design of Sodium-cooled Fast Reactor (SFR) is to meet the safety goals for severe accidents. Among the severe ones, the Unprotected Transient OverPower (UTOP) accidents can lead very quickly to a global melting of the core. UTOP accidents can be considered either as slow during a Control Rod Withdrawal (CRW) or as fast. The paper focuses on fast UTOP accidents, which occur in a few milliseconds, and three different scenarios are considered: rupture of the core support plate, uncontrolled passage of a gas bubble inside the core and core mechanical distortion such as a core flowering/compaction during an earthquake. Several levels and rates of reactivity insertions are also considered and the thermal-mechanical behavior of an ASTRID fuel pin from the ASTRID CFV core is simulated with the GERMINAL code. Two types of fuel pins are simulated, inner and outer core pins, and three different burn-up are considered. Moreover, the feedback from the CABRI programs on these type of transients is used in order to evaluate the failure mechanism in terms of kinetics of energy injection and fuel melting. The CABRI experiments complete the analysis made with GERMINAL calculations and have shown that three dominant mechanisms can be considered as responsible for pin failure or onset of pin degradation during ULOF/UTOP accident: molten cavity pressure loading, fuel-cladding mechanical interaction (FCMI) and fuel break-up. The study is one of the first step in fast UTOP accidents modelling with GERMINAL and it has shown that the code can already succeed in modelling these type of scenarios up to the sodium boiling point. The modeling of the radial propagation of the melting front, validated by comparison with CABRI tests, is already very efficient.

Leakage Flow Influence on SHF pump model performances

Dupont, Patrick,Bayeul-Laine, Annie-Claude,Dazin, Antoine,Bois, Gerard,Roussette, Olivier,Si, Qiaorui Korean Society for Fluid machinery 2015 International journal of fluid machinery and syste Vol.8 No.4

This paper deals with the influence of leakage flow existing in SHF pump model on the analysis of internal flow behaviour inside the vane diffuser of the pump model performance using both experiments and calculations. PIV measurements have been performed at different hub to shroud planes inside one diffuser channel passage for a given speed of rotation and various flow rates. For each operating condition, the PIV measurements have been trigged with different angular impeller positions. The performances and the static pressure rise of the diffuser were also measured using a three-hole probe. The numerical simulations were carried out with Star CCM+ 9.06 code (RANS frozen and unsteady calculations). Some results were already presented at the XXth IAHR Symposium for three flowrates for RANS frozen and URANS calculations. In the present paper, comparisons between URANS calculations with and without leakages and experimental results are presented and discussed for these flow rates. The performances of the diffuser obtained by numerical calculations are compared to those obtained by the three-holes probe measurements. The comparisons show the influence of fluid leakages on global performances and a real improvement concerning the efficiency of the diffuser, the pump and the velocity distributions. These results show that leakage is an important parameter that has to be taken into account in order to make improved comparisons between numerical approaches and experiments in such a specific model set up.

Substance Abuse

Dupont, Robert MediMedia Korea 1986 JAMA-Korea Vol.1 No.13

Leakage Flow Influence on SHF pump model performances

Dupont, Patrick,Bayeul-Laine, Annie-Claude,Dazin, Antoine,Bois, Gerard,Roussette, Olivier,Si, Qiaorui Korean Society for Fluid machinery 2015 International journal of fluid machinery and syste Vol.8 No.3

This paper deals with the influence of leakage flow existing in SHF pump model on the analysis of internal flow behaviour inside the vane diffuser of the pump model performance using both experiments and calculations. PIV measurements have been performed at different hub to shroud planes inside one diffuser channel passage for a given speed of rotation and various flow rates. For each operating condition, the PIV measurements have been trigged with different angular impeller positions. The performances and the static pressure rise of the diffuser were also measured using a three-hole probe. The numerical simulations were carried out with Star CCM+ 9.06 code (RANS frozen and unsteady calculations). Some results were already presented at the XXth IAHR Symposium for three flowrates for RANS frozen and URANS calculations. In the present paper, comparisons between URANS calculations with and without leakages and experimental results are presented and discussed for these flow rates. The performances of the diffuser obtained by numerical calculations are compared to those obtained by the three-holes probe measurements. The comparisons show the influence of fluid leakages on global performances and a real improvement concerning the efficiency of the diffuser, the pump and the velocity distributions. These results show that leakage is an important parameter that has to be taken into account in order to make improved comparisons between numerical approaches and experiments in such a specific model set up.

旅行者의 설사에 새로운 豫防法 : Subsalicylate Bismuth의 豫防的投與에 관해

DuPont, Herbert L.,Sullivan, Peggy,Evans, Dolores G.,Pickering, Larry K.,Evans, Doyle J. Jr,Vollet, John J.,Ericsson, Charles D.,Ackerman, Phillip B.,Tjoa, Weilie S. 藥業新聞社 1980 (月刊) 醫藥情報 Vol.1980 No.11

Leakage Flow Influence on SHF pump model performances

Patrick Dupont,Annie-Claude Bayeul-Lainé,Antoine Dazin,Gérard Bois,Olivier Roussette,Qiaorui Si 한국유체기계학회 2015 International journal of fluid machinery and syste Vol.8 No.3

This paper deals with the influence of leakage flow existing in SHF pump model on the analysis of internal flow behaviour inside the vane diffuser of the pump model performance using both experiments and calculations. PIV measurements have been performed at different hub to shroud planes inside one diffuser channel passage for a given speed of rotation and various flow rates. For each operating condition, the PIV measurements have been trigged with different angular impeller positions. The performances and the static pressure rise of the diffuser were also measured using a three-hole probe. The numerical simulations were carried out with Star CCM+ 9.06 code (RANS frozen and unsteady calculations). Some results were already presented at the XXth IAHR Symposium for three flowrates for RANS frozen and URANS calculations. In the present paper, comparisons between URANS calculations with and without leakages and experimental results are presented and discussed for these flow rates. The performances of the diffuser obtained by numerical calculations are compared to those obtained by the three-holes probe measurements. The comparisons show the influence of fluid leakages on global performances and a real improvement concerning the efficiency of the diffuser, the pump and the velocity distributions. These results show that leakage is an important parameter that has to be taken into account in order to make improved comparisons between numerical approaches and experiments in such a specific model set up.

Bilateral sternocleidomastoid variant with six distinct insertions along the superior nuchal line

Graham Dupont,Joe Iwanaga,Juan J. Altafulla,Stefan Lachkar,Rod J. Oskouian,R. Shane Tubbs 대한해부학회 2018 Anatomy & Cell Biology Vol.51 No.4

Anatomical variations of the sternocleidomastoid muscle (SCM) have been observed to occupy multiple origins and insertion points and have supernumerary heads, sometimes varying in thickness. During routine dissection, a SCM was observed to have six distinct insertions that interface with the course of the superior nuchal line, ending at the midline, bilaterally. This variation was also seen to receive innervation from the accessory nerve as well as the great auricular nerve. To our knowledge, this variant of supernumerary insertions and nerve innervations has not yet been reported. These variants may pose as problematic during surgical approaches to the upper neck and occiput, and should thus be appreciated by the clinician. Herein we discuss the case report, possible embryological origins, and the clinical significance of the observed variant SCM.

Efficacy and Tolerance of a New Anti-Regurgitation Formula

Christophe Dupont,Yvan Vandenplas,SONAR Study Group 대한소아소화기영양학회 2016 Pediatric gastroenterology, hepatology & nutrition Vol.19 No.2

Purpose: Regurgitation is a common physiological phenomenon in infants. The aim of the present study was to eval-uate the efficacy of a new anti-regurgitation (AR) formula (Novalac), thickened with an innovative complex including fibres, on the daily number of regurgitations and to assess its impact on stool consistency and frequency.Methods: Infants younger than five months, presenting at least 5 regurgitations per day were recruited in this trial. The efficacy of the new formula on regurgitation (daily number and Vandenplas score), stool frequency and con-sistency were assessed at day 14 and 90. Growth data were recorded at each study visit.Results: Ninety babies (mean age 9.6±5.8 weeks) were included in the full analysis data set. The mean number of regurgitation episodes at inclusion was 7.3±3.4. In all infants, regurgitations improved after 2 weeks. The daily number of regurgitations decreased significantly (−6.3±3.3, p<0.001) including in those previously fed a thickened formula (−6.2±3.0, p<0.001). There was no significant change in stool consistency at day 14. After 3 months, 97.5% of infants had formed or soft stools. Growth was appropriate with a slight increase of weight-for-age z-score (from −0.5±1.0 to −0.1±0.9) and no change of weight-for length z-score (−0.1±1.1 to −0.1±−1.1).Conclusion: The new AR formula thickened with an innovative complex is very effective in reducing the daily number of regurgitations without having a negative impact on stools consistency.

Ossification of the roof of the porus trigeminus with duplicated abducens nerve

Graham Dupont,Juan Altafulla,Joe Iwanaga,Koichi Watanabe,R. Shane Tubbs 대한해부학회 2019 Anatomy & Cell Biology Vol.52 No.2

Ossification of parts of the intracranial dura mater is common and is generally accepted as an age-related finding. Additionally, duplication of the abducens nerve along its course to the lateral rectus muscle is a known, although uncommon anatomical variant. During routine cadaveric dissection, an ossified portion of dura mater traveling over the trigeminal nerve’s entrance (porus trigeminus) into the middle cranial fossa was observed unilaterally. Ipsilaterally, a duplicated abducens nerve was also observed, with a unique foramen superolateral to the entrance of Dorello’s canal. To our knowledge, there has been no existing report of a simultaneous ossified roof of the porus trigeminus with an ipsilateral duplicated abducens nerve. Herein, we discuss this case and the potential clinical and surgical applications. We believe this case report will be informative for the skull base surgeon in the diagnosis of neuralgic pain in the frontomaxillary, mandibular, orbital, and external and middle ear regions.

Double-Diffusive Convection in Liquid Freon

P. Dupont,O. Gorieu,H. Peerhossaini,M. Kestoras 대한기계학회 1998 Heat transter conference Vol.3 No.1