Pumps modelling of a sodium fast reactor design and analysis of hydrodynamic behavior

[EN] One of the goals of Generation IV reactors is to increase safety from those of previous generations. Different research platforms have been identified the need to improve the reliability of the simulation tools to ensure the capability of the plant to accommodate the design basis transients established in preliminary safety studies. The paper describes the modelling of primary pumps in advanced sodium cooled reactors using the TRACE code. Following the implementation of the models, the results obtained in the analysis of different design basis transients are compared with the simplifying approximations used in reference models. The paper shows the process to obtain a consistent pump model of the ESFR (European Sodium Fast Reactor) design and the analysis of loss of flow transients triggered by pumps coast-down analyzing the thermal hydraulic neutronic coupled system response. A sensitivity analysis of the system pressure drops effect and the other relevant parameters that influence the natural convection after the pumps coast-down is also included.Ordóñez-Ródenas, J.; Lázaro Chueca, A.; Martorell Alsina, SS. (2016). Pumps modelling of a sodium fast reactor design and analysis of hydrodynamic behavior. EPJ Nuclear Sciences & Technologies. 2(38):1-7. doi:10.1051/epjn/201602717238Fiorini, G. L., & Vasile, A. (2011). European Commission – 7th Framework Programme. Nuclear Engineering and Design, 241(9), 3461-3469. doi:10.1016/j.nucengdes.2011.01.052Lázaro, A., Ammirabile, L., Bandini, G., Darmet, G., Massara, S., Dufour, P., … Stempniewicz, M. (2014). Code assessment and modelling for Design Basis Accident Analysis of the European sodium fast reactor design. Part I: System description, modelling and benchmarking. Nuclear Engineering and Design, 266, 1-16. doi:10.1016/j.nucengdes.2013.10.019Lazaro, A., Schikorr, M., Mikityuk, K., Ammirabile, L., Bandini, G., Darmet, G., … Stempniewicz, M. (2014). Code assessment and modelling for Design Basis Accident analysis of the European Sodium Fast Reactor design. Part II: Optimised core and representative transients analysis. Nuclear Engineering and Design, 277, 265-276. doi:10.1016/j.nucengdes.2014.02.029D. Blanchet, L. Buiron, ESFR Working horse description, European Sodium Fast Reactor Consortium? Deliverable SP2.1.2.D1, 2009Mikityuk, K. (2009). Heat transfer to liquid metal: Review of data and correlations for tube bundles. Nuclear Engineering and Design, 239(4), 680-687. doi:10.1016/j.nucengdes.2008.12.014NRC, inTrace v5.0 Theory manual, Field Equations, Solution Methods, and Physical Models(Office for Nuclear Regulatory Research, Washington, 2012), Chap. 1