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International audience; France (CEA and FRAMATOME) and Japan (JAEA, MFBR, and MHI) teams have carried out collaborative works to have common technical views regarding a sodium-cooled fast reactor (SFR) concept. This paper mainly describes the capabilities of ASTRID 600 to demonstrate SFR technologies of both countries. Japan has studied the feasibility of an enhanced high burnup low-void effect (CFV) core and fuel using oxide dispersion-strengthened steel cladding in ASTRID 600, considering Japan’s target for core performance. The neutronics design of the core has satisfied most required design targets and conditions. Regarding passive shutdown capabilities, Japan team has performed a preliminary numerical analysis for ASTRID 600 using a complementary safety device (CSD), called a self-actuated shutdown system (SASS), one of the safest approaches in Japan. Japan’s team used the SASS in place of the hydraulically suspended absorber rod, called RBH, one of the safest approaches of France, to investigate the potential of the SASS as a design measure common to the countries. The preliminary analysis has shown that the SASS can satisfy the countries’ main requirements. This study has also revealed that the mitigation measures of ASTRID 600 against a severe accident are promising to achieve in-vessel retention for both countries.

International audience; After 6 years of conceptual design phase, the French ASTRID project has started at the beginning of 2016, a 4 years basic design phase. The objective of this paper is to show and underline ASTRID progress and status and to give information of what we have intended for the next 2 years. The ASTRID project is based on a very efficient partnership, allowing versatility and manageability. Very high level and up-to-date project management methods are performed, including technical control with engineering System tools and 3D mock-up consolidation.All the industrials partners involved in the project during the last phase have decided to pursue in the ASTRID project, and the strategic partnership with Japan is going to be reinforced.ASTRID design has also evolved, taking into account new progresses on design to reach better consistency according to high level of reliability and safety, consistent with Generation IV objectives. A cost killing methodology is provided and feedbacks will be expected during 2018 and 2019 years. In the same time, an ongoing effort started two years ago is underway to map all the qualification needs and define all associated processes consistent with safety regulator requirement.

In the present study, a CFD model for cavitation simulation have been investigated and compared to experimental results in the case of 3-bladed industrial inducer. The model uses a multiphase approach, based on multiphase mixture assumption. A truncated form of Rayleigh-Plesset equation is used as a source term for the inter-phase mass transfer. The model allows a good prediction of the cavitation inception as well as the main cavity dimensions. The threshold corresponding to the head drop is also well predicted by the model. It was found that the cavitation induced head drop is mainly due to an increase of energy losses and a decrease of the supplied energy. The hydrodynamic mechanism of head drop is investigated through a global and local analysis of the flow field.

In the present study, a CFD model for cavitation simulation have been investigated and compared to experimental results in the case of 3-bladed industrial inducer. The model uses a multiphase approach, based on multiphase mixture assumption. A truncated form of Rayleigh-Plesset equation is used as a source term for the inter-phase mass transfer. The model allows a good prediction of the cavitation inception as well as the main cavity dimensions. The threshold corresponding to the head drop is also well predicted by the model. It was found that the cavitation induced head drop is mainly due to an increase of energy losses and a decrease of the supplied energy. The hydrodynamic mechanism of head drop is investigated through a global and local analysis of the flow field.

In the present study, two CFD methods for cavitation modeling have been investigated and compared to experimental results in the case of 3-bladed industrial inducer. The first model is an interface tracking method and the second is a VOF model. It was found that both models allow a good prediction of the cavitation inception as well as the main cavity dimensions. The threshold corresponding to the head drop is also well predicted by both models. It was also found that the cavitation induced head drop is mainly due to an increase of energy losses and a decrease of the supplied energy. Furthermore, a meridian analysis of the rothalpy evolution clearly demonstrates that the energy losses are mainly located in the channel downstream to the cavity closure. The hydrodynamic mechanism of head drop is explained through a global and local analysis of the flow field. In fact, the leading edge cavitation causes a flow blockage as well as a flow imbalance as it reaches the throat. The pressure is significantly reduced at the pressure side of the leading edge, which allows cavitation occurrence and consequently influences the energy transfer.