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Oscillating-grid turbulence in a homogeneous uid is in equilibrium between the di usion of turbulent energy and the dissipation rate of the energy. Such a ÿeld has been investigated experimentally and analyzed by using the k-turbulence model. Vertical and horizontal components of uctuating velocity have been measured under the vertical oscillation of a square grid. Vertical proÿles of ÿve characteristic quantities, the turbulent energy k, the dissipation rate , the vertical energy ux F, the eddy viscosity t and a lengthscale lt, have been obtained from the measurements. In the model analysis, the governing equations and the boundary conditions have been non-dimensionalized by using the turbulent energy k0 and the dissipation rate 0 which are given virtually at the center of the grid oscillation as boundary conditions. Dimensionless analytical solutions of k; ; F; t and lt have been derived. The experimental data show some relationships existing between the analytical solutions. This shows the application of the k-model to the oscillating-grid turbulence to be valid. The analytical solutions include three model parameters. Their values have been determined from the experimental data. The values of k 0 and 0 have been evaluated by superposing the analytical solutions of k; and F on their experimental data, and have been related empirically to the experimental parameters. Using the empirical relations for k0 and 0 and the analytical solutions, we can estimate k; ; F; t and lt of the oscillating-grid turbulence.

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