## ON THE DECAY OF SHEARLESS WALL BOUNDED TURBULENCE
## ResumoThe decay of turbulence in a wall bounded domain without mean velocity is investigated. Direct and Large-Eddy Simulations, as well as the Eddy Damped Quasi-Normal Marko-vian closure are used. The effect of the finite geometry of the domain is accounted for by introducing a low wave-number cutoff in the energy spectrum of isotropic turbulence. It is found that, once the saturation of the turbulent energy-containing length scale has occurred, the r.m.s. vorticity is decaying following a power law with a -3/2 exponent, in agreement with the helium superfluid experiment of Skrbek and Stalp (2000). The turbulent kinetic energy decay exponent is found to be -2, also in agreement with Skrbek and Stalp. Using scalings deduced from a simple analysis, all data can be collapsed into single curves for both the fixed scale turbulent regime and the final viscous period of decay. A spectral model for inhomogeneous turbulence is finally applied to the decay of turbulence between two plates. It is shown that the results are in agreement with the helium experiment. |

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