Figure 6.

FE simulation of two helically wrapped fibrils. (a) Axial stress distribution in the fibrils for the undeformed (top) and deformed (bottom) states for µ = 0.5. The geometrical scale is compacted 10 times in the axial direction for clarity. (b–d) Stress along the length of the fibrils, and (e–g) normalized displacement ($\overline{u}$, equation (2.4)) along the length of the fibrils for various choices of friction coefficient µ. With no friction (µ = 0), there was no σ or $\overline{u}$ (b,e). As the frictional coefficient increases, the stress and the deformation increases for µ = 0.5 (c,f) and for µ = 2 (d,g). The model parameters are E = 1 GPa, ν = 0.2, λ = 40 µm. (Online version in colour.)