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International audience; One of the main experimental equipment under construction within the Jules Horowitz Reactor isthe LORELEI (Light water One Rod Equipment for LOCA Experimental Investigation). The aim ofthis test device is to study the thermomechanical behavior of the cladding and the fuel rod in order todetermine the radiological consequences in the case of a Large Break LOCA (Loss-Of-Coolant Accident)accident. In order to design appropriately this device it is important to simulate its behaviorin normal operation or in incidental and accidental situations by using a thermal-hydraulic two-phaseflow software. In this paper, we present two different numerical tests corresponding to the two mainworking conditions of the LORELEI device. The first test simulates the working condition of there-irradiation phase, when the device is filled with water and the fuel rod cooled in a natural convectionloop. This test is thought to provide temperature profiles and velocities in the thermosiphoncomponent, both in single and two phase regime, and to determine the power threshold needed tolimits the thermosiphon working conditions. The second test, consecutive to the re-irradiation phase,reproduces the LOCA sequence with the device in a gas environment (steam, helium and hydrogen).For this case, where high temperatures occur, a new dedicated radiative heat transfer module isintroduced. The objective of the simulation is to obtain representative thermal maps of all significativecomponents from the beginning of the LOCA sequence up to the high temperature plateau. Weperform CATHARE-2 computations and compare the results with CFD corresponding simulations.

Acute biliary pancreatitis (ABP) is a serious complication of biliary stones disease and is associated with significant morbidity and mortality. The role of ERCP in the management of ABP has been the focus of discussion in recent years. In this report, we evaluated a protocol of emergency Endoscopic retrograde Cholangiopancreatography (ERCP) (within 24 hours) and early ERCP (within 72 hours). From July 1997 to July 2000, were observed 45 patients (19 man and 26 women) with acute biliary pancreatitis. Mean age of patients was 63.4 years (range 21-87 years). Diagnosis of ABP was based on anamnesis and clinical assessment and was confirmed by specific laboratory data (hyperamylasemia, hyperlipasemia, total and fractionated bilirubinemia, gamma-GT, transaminase, alkaline phosphatase, hypocalcemia, hyperglycemia, leukocytosis). Ultrasound scanning within 24 h of admission was performed in 45 patients (100%) and it revealed gallbladder stones and muddy bile in 39 patients (87%). Computed tomography (CT) performed in all patients, showed a severe acute pancreatitis in the second or subsequent week following admission. The severity of acute pancreatitis was established by Glasgow's criteria and by clinical details of patients. ERCP and Endoscopic Sphinterotomy (ES) was performed in all 45 patients with acute biliary pancreatitis. Twenty-six patients (57%) were classified as having a severe attack (> 4) 19 as having a mild attack by Glasgow's criteria. ERCP associated with ES was performed within 24 hours in 22 patients (49%), 11 (50%) showed a severe attack and 11 (50%) showed a mild attack. A total of 2 complications (4%) occurred and the mortality was of 2 patients (4%). In 23 patients (51%) ERCP and ES was performed within 72 hours after conservative therapy, 8 (35%) showed a mild attack and 15 (65%) showed a severe attack. A total of 5 complications (9%) occurred and the mortality was of 3 patients (6%). Our study showed that ERCP with endoscopic sphincterotomy can be performed safely by skilled endoscopist, without adverse consequences soon after the onset of acute biliary pancreatitis even within the first 24 hours and it showed that is better than ERCP within 72 hours after conservative therapy.

Annals of Microbiology 2007, 57, 645-650

The Westinghouse AP1000 main characteristic that distinguish it with respects to the modern PWRs is the adoption of several Passive Core Cooling Systems (PCCS) to recover the normal operation or to mitigate the consequences in case of accident. In this paper, modeling and nodalisation of the Reactor Coolant System (RCS), the secondary circuit and all the PCCS for the AP1000 reactor have been studied and a 10-in. small break LOCA scenario has been analyzed using CESAR, the thermal-hydraulic module of the ASTEC V2r2 integral code. The simulation results were compared with those coming from the Westinghouse-developed NOTRUMP code used as reference, showing a reasonable agreement. In case of a 10 inches small break LOCA, the results indicate that the PCCS ensure that the fuel and cladding temperature and the other thermal-hydraulic parameters respect the safety criteria and the safety systems perform their design role during the transient, leading the plant to cold shutdown conditions. © 2015 Elsevier Ltd. All rights reserved.

A Severe Accident countermeasure can be the retention of the melted core inside the reactor vessel. A way to achieve this kind of corium retention is by removing heat from the steel vessel by flooding the reactor cavity. A first calculation was performed in order to assess In-Vessel Core Damage Retention (IVR) possibilities for an AP1000 reactor as a consequence of a Beyond Design Basis Accident (BDBA). The computer code used to perform this calculation is ASTEC. ASTEC is an integral code to analyse severe accidents in LWRs, jointly developed by IRSN (France) and GRS (Germany), and it is meant to predict a whole severe accident sequence from the initiating event to source term evaluation inside the containment building. The accidental transient was carried out using ICARE and CESAR modules for the evaluation of the primary system thermal-hydraulic behaviour. The improved debris bed and magma models available in the code last version have been used to describe the late phase of core degradation. In this calculation different assumptions were done regarding the corium, particularly different configurations of the corium relocated in the RPV lower head were considered. The results of the calculations show the effectiveness of the reactor cavity flooding option as a severe accident management strategy.