Shape, force, and energy of helical bundle deformation computed from the finite element model. (A–C) Starting (gray) and final representation (dark gray, blue, and red) of NOMPC for the no-contact (A), frictionless (B), and rough contact models (C). (D) The force per chain is represented as a function of the vertical displacement (Δz) for the three different models (black dashed curve, no contact; blue, frictionless contact; and red, rough contact). These force–displacement curves are per-chain values, and the entire force of the bundle is four times the reported value. (E) The energy is represented as a function of the vertical displacement (Δz) for the three different models (black dashed curve, no contact; blue, frictionless contact; and red, rough contact). These energy–displacement curves are for the entire four-helix bundle. The gray region in D and E represents displacements before helix–helix contact.