NEW APPROACH FOR THE CALCULATION OF TRANSITIONAL FLOWS

In spite of many attempts at modeling natural transition, it has not b een possible to predict the streamwise intensities. A procedure is dev eloped that incorporates some results of linear stability theory into one-equation and stress model formulations. The stresses resulting fro m fluctuations in the transitional region have turbulent, laminar (non turbulent), and large eddy components. Comparison with Schubauer and K lebanoff's experiments have shown that the nonturbulent and large eddy components have a large influence on the streamwise intensities and l ittle influence on the skin friction. Finally, predictions of the one- equation model were as good as those obtained by the stress model.