TRANSP-Class Integrated Analysis Codes
Integrated analysis codes such as TRANSP combine equilibrium, transport, heating, and diagnostics into one time-dependent interpretation of a discharge.
What integrated analysis means
An integrated analysis code takes the full set of measurements from a discharge and produces a time-dependent, physically consistent picture: profiles, power balance, current sources, fast-ion behavior, and fusion output. TRANSP is the long-established reference implementation of this class, and many facilities run codes built on the same philosophy.
Modules under one roof
- Equilibrium reconstruction consistent with measured profiles
- Neutral-beam and radio-frequency heating deposition, often via Monte-Carlo fast-ion models
- Power and particle balance to infer transport coefficients
- Neutron and fusion-rate calculations for comparison with detectors
Interpretive power balance
The heart of interpretive analysis is power balance: given measured profiles and computed sources, the code solves for the heat and particle fluxes that must be flowing, and hence the effective diffusivities. These inferred coefficients are the empirical ground truth against which theory-based transport models are validated.
Fast-ion modeling
Neutral-beam and fusion-born ions are followed with Monte-Carlo particle methods that capture their slowing-down, orbits, and losses. Getting the fast-ion population right is essential because it carries heating, current drive, and, when it goes wrong, drives instabilities.
Between-shot and deep analysis
Simplified configurations run between shots to guide the next experiment; full configurations run afterward for publication-grade analysis. The same code spans both by turning modules on or off and choosing fast or accurate settings.
For a design like the Hyperion breeder, an integrated analysis code is run in predictive mode to project a full discharge, then re-run interpretively once data exists to close the loop between prediction and measurement.