Kelvin–Helmholtz Shear Instability
Kelvin–Helmholtz instability grows on a sheared interface between fluids when destabilizing inertia overcomes stabilizing effects such as surface tension or density stratification. The simulator shows a toy dispersion σ(k) and an interface built from a few growing Fourier modes for visualization only.
Who it's for: Fluid mechanics students needing a bridge between shear layers and billow clouds.
Key terms
- Kelvin–Helmholtz
- Shear instability
- Dispersion relation
- Surface tension
Live graphs
How it works
A cartoon of shear-driven wrinkling: superposed modes with growth rates from a simplified σ(k) kernel, plus the corresponding dispersion curve.
Frequently asked questions
- Is σ(k) derived from the full two-fluid dispersion relation?
- No. It is a compact phenomenological curve used to discuss band-pass growth: long waves feel shear, short waves are damped by the tension proxy.
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