There are approximately 500 nuclear power reactors in operation worldwide with capacity to produce 375 GWe, 28 reactors are under construction and a large number are in different stages of planning and designing. The latest generation of pressurised water reactors (PWR) is designed to minimize the risk of damage to fuel and control rods during potential accidents. Fuel rods may overheat during a loss-of-coolant accident (LOCA) due to either the coupled thermohydraulics and neutronics instabilities or critical heat flux (CHF) events (i.e., sharp reduction of the local heat flux due to nucleate boiling). In the latter, the flow of water/steam and heat can produce local hydrodynamics instabilities that can lead to damages to the cladding, control and fuel rods.
During a LOCA event, the resulting boiling leads to the formation and transport of bubbles of vapour by the high velocity coolant fluid. Bubbles can form clusters or coalesce, resulting in vapour clots or slug flows in the narrow reactor core channels, which in turn affect the designed coolant heat flux. The resulting large temperature system can potentially damage the solid structures (cladding and fuel rods) leading to core melting and fragmentation.
This project aims to improve our understanding of the initial LOCA stages that may lead to a reactor core melting. The project will exploit existing stateof-the-art computational methods to investigate CHF in tube bundles during a LOCA event. This will involve the development of CFD models for:
(a) Multi-scale heat and fluid flows using high-order accurate schemes coupled with adaptive LES turbulent methods;
(b) Heterogeneous and homogeneous nucleation mechanisms; and
(c) Prediction of heat transfer and bubble size distribution.
The successful candidate should have (or expect to achieve) a minimum of a UK Honours degree at 2.1 or above (or equivalent) in Mathematics, Physics, Nuclear, Mechanica, Chemical or Civil Engineering.
Essential Background in Advanced mathematics, fluid dynamics and programming.
Knowledge of: Fluid dynamics; Numerical methods; Computational linear algebra; Fortran or Python or C languages.
Formal applications can be completed online: http://www.abdn.ac.uk/postgraduate/apply
. You should apply for Degree of Doctor of Philosophy in Engineering, to ensure that your application is passed to the correct person for processing.
NOTE CLEARLY THE NAME OF THE SUPERVISOR AND EXACT PROJECT TITLE YOU WISH TO BE CONSIDERED FOR ON THE APPLICATION FORM.
Informal inquiries can be made to Dr J Gomes ([email protected]
) with a copy of your curriculum vitae and cover letter. All general enquiries should be directed to the Postgraduate Research School ([email protected]
J. Bakosi et al. (2013) Large-Eddy Simulations of Turbulent Flow for Grid-to-Rod Fretting in Nuclear Reactors, Nuclear Engineering and
Design 262: 544-561.
J. Gomes et al. (2011) Coupled Neutronics-Fluids Modelling of Criticality within a MOX Powder System, Progress in Nuclear Energy 53: 523-552.
Buchan et al. (2012) Simulated Transient Dynamics and Heat Transfer Characteristics of the Water Boiler Nuclear Reactor – SUPO – with
Cooling Coil Heat Extraction, Annals of Nuclear Energy 48: 68-83.
S.Mimouni et al. (2011) Combined Evaluation of 2nd-Order Turbulence Model and Polydispersion Model for Two-Phase Boiling Flow and
Application to Fuel Assembly Analysis, Nuclear Engineering and Design 241: 4523-4536.