1,721,319 research outputs found
CATHARE 2 V 1.4 Capability to Simulate the Performance of ISOLATION CONDENSER SYSTEMS with Thermal Valve
No full textENEA (Italy) in co-operation with CEA (France) has carried out an R&D activity aimed at increasing the reliability of Decay Heat Removal (DHR) passive systems that implement in-pool heat exchangers. The main outcome reached was the definition of a device, called Thermal Valve (TV), able to avoid the installation of mechanical valve on the primary circuit, thus reducing thermal-mechanical constrains and thermal-hydraulic instabilities. This paper presents a preliminary assessment performed with CATHARE of this innovative device. In the first part the code capability to simulate in-pool heat exchangers is verified against experimental data of the PANDA facility, that are available within the frame of the ISP 42. In the second part a CATHARE calculation showing the performances of the PANDA passive condenser with TV (start-up and shutdown) is described
ENEA's activity in the Safety Analysis of the gas cooled eXperimental Accelerator Driven System (XADS)
No full textThis document deals with the activity performed by ENEA as contribution to the deliverable 'Transient Accident Analysis of the Gas-Cooled XADS'. It provides the results of the analyses concerning two accidents: Loss of Flow (LOFA) and water ingress in the Primary Coolant System. In spite of an upgrading of the design, required to guarantee the decay heat removal in depressurised conditions, the plant response to an unprotected LOFA remains critical thus emphasizing the need of a beam shutdown system with a very high degree of reliability. Preliminary evaluations on the risk of recriticality due to water ingress in the Primary Coolant System at shutdown conditions shown negative values of the reactivity inserted for all the transients considered. Although conservative and different scenarios have been considered, these analyses have to be revisited once a complete definition of the SCS loop will be available
SPES3-IRIS Facility RELAP5 Base Case Transient Analyses for Design Support
No full textThe SPES3 facility simulates with 1:100 volume scale and 1:1 height scale, the IRIS (International Reactor Innovative and Secure) primary, secondary, containment and safety systems. It will be built at SIET laboratories and operated at the IRIS nominal conditions. A RELAP5 nodalization, based on the 'Conceptual design', has been developed and used during the design phase for obtaining feedback information on the facility design verifying SPES3 capability to simulate the physical phenomena of the postulated accidents. At this end five base test transient cases were chosen among the tests specified in the SPES3 test matrix. That document reports a detailed analysis of the results of the base transient cases simulation
Final SI CATHARE ModuleDeliverable D22 of DEEPSSI project
No full textThis report contains in electronic format the set of subroutines and input decks for the CATHARE code. The set of subroutines coupled with an input deck form the CATHARE module that is dedicated to simulate the steam injector behaviour. The subroutines activate the correlations specifically developed for SI, whereas the input deck provides lD geometrical description, boundary and initial conditions. The DEEPSSI derivable D23 explains how to use them to reproduce the calculations performed within the project and to support the simulation of generic Steam Injector systems
Description of the SI CATHARE module (models, utilisation)Deliverable D23 of DEEPSSI project
No full textThe purpose of this document is to provide a description of the set of subroutines and input decks for the CATHARE code reported in Derivable D22 of the DEEPSSI project (ENEA report FISP-127-031). The set of the subroutines with an input deck form a CATHARE module that is dedicated to simulate the steam injector behaviour. The subroutines activate the specific correlations, whereas the input deck provides lD geometrical description, boundary and initial conditions. The document explains how to use them to reproduce the calculations performed within the DEEPSSI project and to support the simulation of generic Steam Injector systems
IVCRS - Half Yearly Progress Report
No full textThis report presents the status of the In-Vessel Core Retention Strategy Concerted Action (IVCRS CA) carried out within the frame of the 4th Framework Program funded by the European commission (after 6 months duration). The progress realized in WP1, Definition of Technical Requirements and Safety Approach, shows that the proposed approach fit well the existing safety requirements for future LWRs. In WP2, State of the Art for In-Vessel Retention, literature surveys on different topics have been carried out: corium pools, thermal-hydraulics of a gap, reactor pit flooding etc÷÷.. In WP3, Research of Prevention and Mitigation Means, proposals have been made for the research of alternative in-fuel and in-core structure, in order to prevent core fusion. On the other hand, different concepts of in-vessel core retention have been identified by the partners of the project. Finally in WP4, a preliminary assessment of the DIVER concept by the mean of computer code calculations has just started
Post-Test Calculations with ISAS-ITER Systems for ICE Experiments
No full textIn the frame of the Safety and Environment tasks of the European Technology Program for ITER project one of the main issue is the validation of the computer codes and models used as reference for ITER safety analysis to obtain acceptance by licensing authorities. In the context of the fusion field facilities the data useful for validation are very limited because only few experimental machines are available as operating experience. To overcome this problem several integral and separate test experiments have been undertaken in the ITER program. The paper deals with the validation of the ISAS-ITER system for ITER safety analysis against the results obtained in the experimental campaign carried out during the year 2000 in the ICE (Ingress of Coolant Event) facility built in JAERI, Japan. ISAS-ITER links together the computer codes ATHENA (for thermal-hydraulic transient) and INTRA (for containment simulation). The experimental campaign investigated the discharge of water and steam from a pressurised container towards a vacuum vessel volume (VV) and a suppression tank. The VV represents the typical configuration of the plasma chamber, scaled respecting the geometrical dimensions of the ITER-FEAT design. Choked flow conditions, condensation, jet impingement and evaporation phenomena are involved in the tests reproducing different experimental conditions. ISAS-ITER post-test calculations, presented in the paper, show a quite good agreement with the ICE experimental data and the discussion of the results allows to detect the analytic al model approximations that are the cause of the main discrepancies
SPES 3-IRIS Facility Nodalization for RELAP5 Mod. 3.3 Code and Steady State Qualification
No full textThe primary goal of this document is to describe the SPES3-IRIS facility nodalization for the RELAP5 Mod. 3.3 code, which has been developed to support the design of the primary, secondary and containment systems of the experimental plant
BWR Physics and Thermalhydraulics Complementary Actions tot he IPSS-BWR R&D Clustei - Final Summary Report
No full textDesign and Development of a Steam Generator Emergency Feedwater Passive System for Existing and Future PWRs Using Advanced Steam Injectors (DEEPSSI)
No full textAmong passive systems, the steam injectors (also called 'condensing ejectors' or 'steam jet pumps') are one of the most interesting apparatus. The reactor application envisaged here is the Steam Generator Emergency FeedWater System (EFWS) of Pressurised Water Reactors (PWRs). Considering the European Pressurized Water Reactor (EPR) and the Russian WWER-440/213, functional specifications heave been established for each plant regarding the operation of a Steam Injector system. Experimental studies address the development of an innovative steam injector design and the constitution of a significant database allowing the elaboration of dedicated steam injector correlations and the validation of a computational model. The modelling studies are undertaken using the CATHARE thermalhydraulic computer code and in particular its one-dimensional module. Significant code adaptations are necessary (numerics, geometrical modelling capabilities). Correlations dedicated to the steam injector nominal functioning will be derived including a pertinent physical description of the domain where this nominal functioning can be obtained. CATHARE plant models of the reference PWR reactors will be used to calculate some accidental transients and to assess the plant responses with steam injector based EFWS. The evaluation of this new safety system will be made by making comparisons to existing solutions
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