The FRANTIC model performs a very fast 1d neutral gas transport calculation for tokamak core plasmas, taking into account charge exchange and impact ionization atomic reactions in a simplified nested cylindrical flux surface geometry. This model is a generalization of the original code by Steve Tamor,
S. Tamor, J. Comput. Phys. 40 (1981) 104.with extensions to permit multiple ion and neutral species including Helium as well as Hydrogen isotopes. The calculation takes as input a neutral source, which can be an "edge" influx neutrals representing recycling or gas flow, or, a "volume source" due to recombination and/or the charge exchange halo around injected neutral beams. The main calculation is called once for each neutral source. All sources are assumed to be distributed evenly around the circularly shaped flux surfaces. The model also accepts as input data profiles of the rates of depletion of neutrals by collisions with fast ion species-- a dominant process in low density intensely heated tokamak experiments with signifant fast ion density fractions. FRANTIC then calculates neutral density and "temperature" and toroidal velocity profiles for each of the neutral species associated with the given neutral source. Particle, momentum and energy sources/sinks are calculated, as well as complete particle, momentum and energy balance information for each neutral specie. Atomic physics data comes from the PREACT module, which includes ADAS and is an available component of the NTCC library.