Top: bulk density against diameter of dust aggregates. The dotted lines show the numerically calculated bulk densities, while the others show the analytical relation (Equation (4)). The blue and orange lines show ice and silicate dust aggregates, whose material densities are 1.45 and 2.65 g cm⁻³, respectively. The solid and dashed lines show monomer radii of 0.1 and 1.0 μm, respectively. Bottom: relative error to the analytical relation (Equation (4)) of the numerically calculated bulk density.