Modelling charged-particle transport and heating in fusion plasmas

 The project will investigate a very important aspect of inertial confinement fusion:
 the internal heating by fusion products. Recently, inertial confinement fusion has 
 made considerable progress reaching the stage of substantial internal heating and 
 later positive energy outcome (ignition) in several experiments. However, it requires
 extremely high densities and temperatures which make modelling very hard. This is
 particularly true for the interaction of the alpha-particles created in fusion events
 as the high density creates very strong interactions.

 The project will be done in cooperation with an industrial partner, First Light Fusion
 (FLF) near Oxford, and is fully funded via ICASE by EPSRC. Additional funds will be 
 available to spend some time at their facilities. FLF is pursuing controlled nuclear
 fusion using a scheme based on the ‘volume ignition’ concept. Achieving maximum energy 
 gain requires a detailed understanding and high-fidelity modelling capability of the 
 processes by which the alpha-particles created are transported through the fuel and 
 heat the plasma. This principally requires knowledge of the ‘stopping power’ of fusion
 fuel, a topic covered extensively in literature, but remains uncertain for the extreme
 conditions during fusion burn. Moreover, for a strongly burning target, where > 50% of
 the DT fuel is burned, the composition of the fuel changes substantially. This is 
 expected to impact the stopping power as well as the equation of state and heating 
 energetics of the fuel. This project seeks to evaluate and contrast the 
 state-of-the-art in these fields and verify against first-principles simulations and 
 experiments. It will also seek to establish a minimum credible capability for burn 
 dynamics that will inform FLF’s strategic plan for developing our ICF design codes.

 Main questions to be answered during the project are: What are the differences between
 the current state-of-the-art stopping power models and how do these compare to 
 first-principles simulations? What is the most minimum credible capability required 
 for accurately modelling fusion burn in an integrated simulation? Can an experimental 
 platform be designed which enables discrimination between these models? What are the 
 prospects and challenges associated with in-line equation of state mixing to 
 accommodate neutron escape and fuel transmutation in strongly burn fusion plasmas, and
 the deleterious influence of high-Z mixing from the pusher? Of course, these questions 
 will be tackled in cooperation with the team at FLF but will have significant parts
 reserved for the studentship.