THERMONUCLEAR BURN PERFORMANCE OF VOLUME-IGNITED AND CENTRALLY IGNITED BARE DEUTERIUM-TRITIUM MICROSPHERES

A parametric study of the burn performance (measured by the fuel energy gain) of compressed deuterium-tritium fuel microspheres, with parameters of interest to inertial confinement fusion, has been performed by 1-D numerical radiation-hydrodynamics simulations. Both volume-ignited and centrally ignited (either initially isobaric or isochoric) configurations are considered. An overview is given of the relevant ignition conditions. For the first time a scaling law is presented for the limiting gain of volume-ignited fuels. Scaling laws are also given for the limiting gain of centrally ignited assemblies, which have the same functional dependences as predicted by previous analytical models, but different numerical coefficients. The advantage of isochoric assemblies over isobaric ones is confirmed, but found to be smaller than previously reported. The potentials of volume-ignited and of centrally ignited, isobaric assemblies as functions of the energy, density and pressure are also critically compared.