Directions in Radiation Transport Modelling

P Nicholas Smith, C Pain, A Buchan, S Dargaville, J Lillington


Radiation transport modelling has come a long way in the last 50 years: 2D models have been replaced by 3D models; multi-group energy schemes have been replaced by continuous energy nuclear data representations in Monte Carlo models; accurate 3D geometrical representations are available, including import from CAD files.

More exciting advances are on the horizon to increase the power of simulation tools. The advent of high performance computers is allowing bigger, higher fidelity models to be created, if the challenges of parallelization and memory management can be met. 3D whole core transport modelling is becoming possible. Uncertainty quantification is improving with large benefits to be gained from more accurate, less pessimistic estimates of uncertainty. Advanced graphical displays allow the user to assimilate and make sense of the vast amounts of data produced by modern modelling tools. Numerical solvers are being developed that use goal-based adaptivity to adjust the nodalisation of the system to provide the optimum scheme to achieve the user requested accuracy on the results, thus removing the need to perform costly convergence studies in space and angle etc. More use is being made of multi-physics methods in which radiation transport is coupled with other phenomena, such as thermal-hydraulics, structural response, fuel performance and/or chemistry in order to better understand their interplay in reactor cores.

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