Smagorinsky Constant Distribution and Turbulent Energy Dissipation in High Reynolds-Number Cavity Flow

This study experimentally investigates lid-driven cavity flow at high Reynolds numbers (Re = 3 × 105–1 × 106) using particle image velocimetry. The spatial distribution of root mean square (RMS) velocity, turbulent kinetic energy dissipation rate, and the Smagorinsky constant is analyzed to reveal key turbulence characteristics. The results show that: (1) the RMS velocity increases significantly in the near-wall region with Reynolds number, reaching a peak of 0.43 m/s on the downstream near-wall surface at Re = 1 × 106, while remaining below 0.1 m/s in the core region due to flow stability suppressing turbulence fluctuations; (2) the turbulent kinetic energy dissipation rate exhibits significant spatial nonuniformity near the wall with a peak value of 0.6 at Re = 1 × 106; as the Reynolds number increases, high dissipation regions extend further into the cavity interior and evolve into multiscale fragmented structures; (3) the Smagorinsky constant is close to zero near the cavity wall, gradually increases with distance from the wall, reaches a maximum, and then decreases to zero at the cavity center. As the Reynolds number increases, the overall Smagorinsky constant increases with a more significant rise in its maximum value at higher Reynolds numbers, indicating stronger eddy viscosity. These findings provide experimental insights for improving the nonuniform parameterization in eddy viscosity models for large-eddy simulations.