The cash flow fade model is a valuation model based on DCF that takes into account the phenomenon of gradual convergence of ROCE to WACC after the end of the Explicit forecast period. In this model, Free cash flow decreases gradually after the end of the Explicit forecast period.

(See Chapter 32 Capital structure and the theory of perfect capital markets of the Vernimmen)

To know more about it, look at what we have already written on this subject