1 Commits

Include renames

Author	SHA1	Message	Date
Omar SobhandClaude Fable 5	6510045b5d	rtx-fea: wire NonlinearStaticAnalysis — Newton on the consistent tangent, MMS-verified at second order ... NonlinearStaticAnalysis::run returned DVector::zeros unconditionally, like ModalAnalysis and DynamicAnalysis before their repair. It is now full Newton-Raphson on R(u) = f_ext - f_int(u): - ElementMatrixComputer::compute_internal_force_and_tangent integrates f_int = int(B' sigma dV) and K_T = int(B' D_T B dV) in ONE quadrature sweep from a constitutive closure in the element's reduced Voigt space — computing both together is what keeps the tangent consistent with the stress, which is what quadratic convergence rides on. - materials::reduced_constitutive bridges the Material trait (Voigt-6) to that closure: 3-D passes the total strain straight through; 2-D supports the linear plane-stress closed form and refuses nonlinear materials explicitly, since plane-stress condensation of a general law needs a per-point iteration that is not implemented yet. - Dirichlet DOFs are held at their (load-scaled) values and Newton runs on the free DOFs, so the prescribed motion enters through f_int itself — no K_fc bookkeeping to get wrong. Body force enters via set_body_force, the same hook pattern the CFD solvers use for manufactured solutions. Uniform load stepping; other strategies and quasi-Newton refuse explicitly. - StandardFiniteElement::compute_internal_forces, previously a zeros stub, now delegates to the same machinery. - Mesh::validate is now called in run() (the old TODO), and NonlinearConfig gained a Default. Verified two ways (tests/nonlinear_static.rs): - Equivalence: with LinearElastic the loop lands on the directly assembled linear solution to 1e-10 in exactly one Newton step — same B, quadrature and solver, so any disagreement is the nonlinear assembly. - Manufactured solution with a genuinely nonlinear material (energy W = 1/2 e'De + alpha/3 I1^3, so stress and tangent are exact derivatives; body force by central differences of the closed-form stress): L2 errors 6.032e-2, 1.780e-2, 4.595e-3 on 2/4/8 Hex8 — observed orders 1.76 and 1.95, climbing to the theoretical 2. The forcing contains the nonlinear term, so the order is reachable only if it is solved; an inconsistent tangent is caught separately by the iteration-count bound. This unblocks ECSW model-order reduction, which needs a working nonlinear solve underneath it. 551 rtx-fea tests, 0 failing. Co-Authored-By: Claude Fable 5 <[email protected]>	2026-08-19 19:44:08 -07:00