A study of annular slurry jet for abrasive waterjet cutting
A Study of Annular Slurry Jet for Abrasive Waterjet Cutting
The effect of jet injection geometry on two-dimensional momentumless wakes
It is shown experimentally that a two-dimensional momentumless wake is strongly dependent on the jet injection configuration of the model. Namely, the decay rate of mean velocity overshoot ranged from x−0.92 to x−2.0 for three different configurations, while the spreading rate ranged from x0.3 to x0.46 for those same configurations. The magnitude of axial turbulence intensity was also found to depend on model configuration. On the other hand, the rate of decay of axial turbulence intensity was the same (x−0.81) for all three models. In all cases the mean shear and Reynolds stress decayed rapidly, leaving nearly isotropic turbulence beyond 30 or 40 model diameters. Appropriate length- and velocity scales are identified which normalize the mean velocity profiles into self-similar form. The shape of the normalized profile, however, was different for each configuration, indicating again that the initial conditions are felt very far downstream.
The Game Planners: Transforming Canada's Sport System.
The Game Planners studies the policy-making process in six Canadian national sports organizations, each of which deals with a different high-profile Olympic event. The authors argue that the creation of a "high-performance" sport system in Canada is due to pressure from three areas: the Canadian government, the physical education profession, and the sports community.