Fig. 13.

Impact of time step size on the relative error for the different combinations of forces and numerical solvers tested on the three model problems (i)–(iii). (a–c) Convergence study for the relaxation experiment (i), initial separation 0.3 cell diameters, (d–f) convergence study for adhering cells (ii), initial separation 1.15 cell diameters, (g–i) convergence study for a monolayer population of 38 (initially 19) cells and (j–l) convergence study for a monolayer population of 74 (initially 37) cells (iii). The numerical solver used was (a, d, g, j) the forward Euler method, (b, e, h, k) the midpoint method and (c, f, i, l) the Adams–Bashforth method. The axes of the plots are in logarithmic scale. The dotted lines show a linear (for plots (a, d, g, j)) and a quadratic function (all other plots) to facilitate observation of the convergence order