Abstract
The free decay of two-dimensional turbulence is simulated by direct numerical integration of the incompressible Navier-Stokes equations at resolutions and, for flows with symmetries, . At early times, quasirectilinear vorticity-gradient sheets develop, with a thickness decaying exponentially in time until dissipation becomes relevant. The energy spectrum then displays a range with . At later times, we observe a transition to . Vorticity gradients are then distributed on reconnecting, elongated, dissipative structures.
- Received 12 August 1985
DOI:https://doi.org/10.1103/PhysRevLett.57.683
©1986 American Physical Society