highturbulence

High turbulence is a term sometimes used in fluid dynamics, meteorology, and engineering to describe turbulent flows that exhibit exceptionally strong, erratic fluctuations and a broad spectrum of eddy scales. It is not a formal phase but a descriptor for extreme instances of turbulence, where chaotic motion, rapid velocity fluctuations, and strong mixing persist over significant time and length scales. Typical features include high Reynolds numbers, large instantaneous velocity and pressure fluctuations, and a significant transfer of kinetic energy from larger to smaller eddies in the energy cascade.

Quantitative descriptors include turbulence intensity Tu, defined as the root-mean-square of velocity fluctuations divided by the mean flow, which is much higher in high turbulence; the Reynolds number Re; the dissipation rate ε; and the Kolmogorov scale η, which is small relative to the largest flow scales.

Where it occurs and why it matters: in the atmosphere, high turbulence is common in convective storms, jet streams, and wind shear; in oceans, in strong currents and near topographic features; in engineering, in aircraft wakes, combustors, and turbomachinery. It affects drag, lift, structural loading, noise, and mixing efficiency.

Modeling and measurement: resolving high turbulence requires high-fidelity approaches such as large-eddy simulation (LES) or direct numerical simulation (DNS); for practical engineering, Reynolds-averaged Navier–Stokes (RANS) methods may struggle. Observations rely on hot-wire anemometry, pitot probes, LIDAR, Doppler radar, and particle image velocimetry.

Overall, high turbulence describes the upper end of turbulent intensity, emphasizing the challenges it poses for prediction and control in natural and engineered systems.