Supporting research – integration Supporting research – integration of innovative reactor physics methods of innovative reactor physics methods

into transient criticality modelling: into transient criticality modelling: Towards a Next Generation FETCHTowards a Next Generation FETCH

Overview of new methods integration into FETCHOverview of new methods integration into FETCH• Robust, adaptive RT methods

Adaptivity in space, energy, angle and time (full adaptivity)

Robust, sub-grid scale methods for numerical stability

Fast hierarchical solvers in space and angle

• Robust, CFD methods for systems with shocks

New schemes for modelling shocks

Towards an unstructured mesh FETCH capability

• Uncertainty Propagation Methods

SFEM for RT

SFEM for multiphase CFD

Coupled modelling SFEM

Fully adaptive RT methods tailoring themselves to the Fully adaptive RT methods tailoring themselves to the physics of the problem (to a given resolution scale).physics of the problem (to a given resolution scale).

Fully adaptive, fast, robust RT framework

(with appropriate adjoint error metrics)

Adaptive spatial meshing Anisotropic adaptivity in angle

Adaptivity in energy Adaptivity in time

Hierarchical solvers

Sub-grid scale

stabilisation

Shock wave capturing, unstructured Multi-phase Shock wave capturing, unstructured Multi-phase flow Modellingflow Modelling

• Multi-phase flow modelling is currently structured mesh based with a pressure corrected shock capturing scheme

• New developments to include unstructured capability as well as numerically “robust” Riemann based shock capturing schemes.

Results from a expanding shock wave in a postulated waste repository scenario

Uncertainty Methods for Improved Engineering designUncertainty Methods for Improved Engineering design

Methods to improve the design of complex engineering systems subject to multiple uncertainties

Uncertainties during engineering design can affect the system

• Safety

• Reliability

• Performance

• Cost

• Risk

Multiphysics SFEM uncertainty methodsMultiphysics SFEM uncertainty methodsNew approach for modelling New approach for modelling multiple uncertaintiesmultiple uncertainties using using stochastic finite elementsstochastic finite elements

Fluid dynamics processes Nuclear ProcessesInput uncertainties

Probability distributions of outputs

Power, fission rate, temperatures, pressures

Funding of these initiativesFunding of these initiatives

• Five year RAEng Fellowship in Uncertainty Methods

• Eng Doc Student on uncertainty in nuclear data in collaboration with Nexia/Serco Assurance – student David Perry

• EPSRC student underpinning the group’s work on shock wave modelling, unstructured multiphase flow – work towards an unstructured mesh FETCH capability – student Justin Hadi

• KNOO funded EPSRC student on SFEM for single phase flow

- student Andrew Hagues

• Part time Imperial PRI/AWE PhD student on radiation methods

- student Simon Merton

• Imperial/Rolls-Royce Eng Doc on radiation methods

- student Christopher Baker

• Imperial/Rolls-Royce Eng Doc on thermal-hydraulics

- student Emily Julian