The Regularized Rotational Vector Field (RRVF) Model: A Universal Amplitude Envelope and a Reproducible Numerical Audit

We study a three-component vector field on a one-dimensional periodic domain, governed by nonlinear advection, viscous diffusion, orthogonal rotation, and nonlinear absorption damping. Applying the maximum principle to the squared norm shows that the amplitude M(t) is non-increasing and obeys an explicit universal envelope. A deterministic finite-difference experiment and an exact discrete energy audit close to round-off when the Euler increment is included. All tables, figures, and numerical results are fully reproducible via the accompanying Jupyter notebook (RRVF_audit.ipynb).