Fig. 2. Evolution of pore-size distribution over time according to Eq. [24] with no decay, a drift term v(r,t) = u(r)w(t) where w(t) is given by Eq. [14], with a = 0.01 d^-1, b = 5 µm, <r₀> = 7.5 µm (upper insert), and u(r) is given by Eq. [16] with u_o = 0.5 (lower insert), and a dispersion term D(r,t) = -(r)v(r,t) where (r) is given by Eq. [16] with: (a) _o = 0.25 and (b) _o = 0.05. The initial distribution is again given by Eq. [5] with _s = 0.469, _r = 0.191, = 0.253, and r₀ = 7.3 µm.