The prediction of water-subcooled flow boiling critical heat flux (CHF) in peripherally nonuniform heated tubes with or without swirl flow promoters is accomplished using a model based on the liquid sublayer dryout mechanism recently proposed by the authors. Peripheral nonuniform heating and/or twisted-tape inserts are properly and simply accounted for in the model, originally developed for uniform heating and straight Row. Simultaneous occurrence of the two events is also well predicted by the model. Although initially formulated for operating conditions typical of the thermal hydraulic design of Fusion reactor high heat flux components, the model is proved to give a satisfactory answer for the prediction of the CHF under more general conditions, provided local thermodynamic conditions of the bulk Row al the CHF are sufficiently far from the saturated state.