Rayleigh-Bénard Convection — Onset & Roll Patterns

Ra / Ra_c: 1.00 Wavenumber k: 3.12 Animate rolls Sweep Ra

Rayleigh-Bénard: Ra = gαΔTh³/(νκ). Neutral stability curve: Ra(k) = (k²+π²)³/k². Minimum at k_c≈3.117, Ra_c≈1708. Above Ra_c, rolls form with wavenumber near k_c. Animation shows convective rolls with velocity streamlines when Ra > Ra_c.