Normalisation parameter m_norm in the mass-size relation as a function of the volume-filling factor μ, calculated using Eq. (5), for different f_DGMF at fixed α = 1.35, m_min = 100 M_⊙ and γ = 1.77. We also show the μ values, obtained using the fixed Sgr B2 relation. Note that for high μ and low f_DGMF values, we obtain mass-size relations yielding clump populations where the least dense clump, given by the clump with the highest mass (m_max), is less dense than the interclump density n_interclump, in contradiction with the very definition of a clump as an overdensity; we clearly indicated these models in red in the plot. We will use the f_DGMF value that allows us to explore a widest possible range of μ, f_DGMF = 0.8, to investigate the impact of increasing μ on the reflected X-ray signal (see Fig. 7).