Flux distributions in stable criticality waves

An analysis is presented of so-called self-stabilizing criticality waves, as can be ignited in originally subcritical systems under the condition that the burn up dependent properties of the system satisfy certain requirements, as was shown in a previous publication for an analytically solvable model. For the solution of the analytically solvable model (as far as the asymptotic waves are concerned) a new approach was adopted, based on taking the flux-fluence space as a starting point. In this way the expressions for ignition condition, wave form, amplitude (i.e. reactor power) and phase velocity are obtained in a more systematic way than before. The analysis is extended to skew criticality waves by adopting cubic flux-fluence trajectories. From the parameters of these trajectories the parameters of the associated burn up functions and the wave properties are inferred. For a particular case the results are corroborated by a computer simulation.