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QF Solver 0.2.5a0 formula inventory

This inventory defines formulas to audit and verify. It does not select a new constitutive model or authorize implementation.

ID Capability Governing relation Existing basis Required decision/proof
F-01 Global equilibrium R(u, q, lambda) = Fint - lambda Fext + Fc = 0 separate nonlinear/contact residuals sign convention and one common residual contract
F-02 Full Newton K_T delta_u = -R, u_{i+1}=u_i+delta_u small-strain and geometric loops one convergence policy and tangent composition
F-03 Small strain epsilon = sym(grad u) common J2 element contract preserve 0.2.4 behavior
F-04 J2 yield f = sigma_eq - (sigma_y + H alpha) VonMisesElastoplasticMaterial re-derive convention and cyclic limitations
F-05 J2 flow/return associative deviatoric radial return existing material analytical path and state verification
F-06 J2 tangent C_alg = d sigma_{n+1}/d epsilon_{n+1} existing algorithmic tangent FD sensitivity near elastic/plastic transition
F-07 Finite kinematics F = I + Grad_X u TET4 TL kernel approve reference/current configuration conventions
F-08 Green-Lagrange strain E = 0.5 (F^T F - I) TET4 TL kernel objectivity and element FD proof
F-09 TL stress/work conjugacy S conjugate to E, P = F S StVK TET4 approve material measure for each model
F-10 Internal virtual work delta Wint = integral(delta E : S dV0) TL assembly internal force and energy derivative FD
F-11 Tangent decomposition K_T = K_material + K_geometric + K_contact separate paths exist sparse common assembly and FD consistency
F-12 Linear buckling (K + lambda K_G) phi = 0 or sign-equivalent form bounded sparse TET4/HEX8 route preload/sign/normalization convention
F-13 Arc length g(delta u, delta lambda, ds) = 0 sparse augmented correction helper choose one Crisfield/Riks constraint and sign rule
F-14 Normal gap g_n = (x_s - x_m) dot n_m contact package orientation, projection and finite-sliding update
F-15 Normal contact complementarity or approved regularization active-set contact exists choose multiplier/penalty/augmented formulation
F-16 Coulomb friction ||t_t|| <= mu t_n, stick/slip complementarity regularized experimental path optional objective frame/state formulation
F-17 External work incrementally consistent Wext partial nonlinear work diagnostics load-path integration convention
F-18 Energy balance Wext - Ue - Dp - residual_terms = 0 not fully qualified define treatment of contact/friction work
F-19 Plastic dissipation Dp >= 0 for the retained associative J2 model material states per-increment and accumulated proof
F-20 Transaction state_committed unchanged until accepted increment MaterialStateSession extend to contact/continuation and adversarial proof

Formula review checklist

For each formula before coding:

  1. cite the reference or existing controlled derivation;
  2. declare tensor ordering, signs, configuration and units;
  3. identify work-conjugate measures;
  4. derive residual and consistent tangent together;
  5. define analytical and finite-difference checks;
  6. record singular/degenerate cases;
  7. obtain Owner approval for any scope-changing constitutive assumption.