Modelling of a Neutron Source Test Bed for the Fusion Fuel Cycle
Predicting with high accuracy (low uncertainty) the performance of tritium breeding systems
is a must for design engineering of future fusion devices. Current modelling relies on scant
experimental data and is known to have uncertainties that if realised in a real system would
potentially create a tritium shortfall in the fuel cycle of a fusion power plant. LIBRTI is
a UK programme to develop a combined experimental test platform and model verification
architecture to reduce these design uncertainties. A simple, but flexible pincell geometry
containing industry standard ceramic breeder material surrounding a market-leadingDT-based
neutron source is found to produce sufficient levels of tritium to be readily measurable with
the well-established liquid scintillation techniques for tritium accountancy. Modelling of the
potential for interference of the measurements due to permeation of tritium from the neutron
source itself indicate that, depending on scenario, there will be at least hours, and potentially
days or more, of viable measurement data in each experiment even before considering any
special design to mitigate the permeation. The analysis is used to demonstrate that LIBRTI
will be able to meet its objectives of providing a platform for measurable testing of larger
scale tritium breeding experiments.