Abstract:
Under the closure of the averaged boundary layer equations the main attention has been concentrated on the development of turbulence models and numerical methods, the analysis of effect of the free-stream leading and the outer edge turbulence parameters on the transitional characteristics of the flow and turbulence at near a wall. For research of the dynamic and thermal characteristics of the wall boundary layers the different variants of classical and modified one- and two-parametric turbulence models allowing by continuous manner to computer a full stream region with laminar, transitional and turbulent flow regimes at high free stream turbulence intensity have been analysed. The two common research ways for the better description of existing experimental and theoretical research data for the transitional structure of a boundary layer at a variation from low to high local turbulent Reynolds numbers have been proposed. An effect of the scale of free stream turbulence on the averaged dynamic and turbulence characteristics of a transition have been studies numerically in details. The predicted results on the basis of $k$-$l$ and a number of $k$-$\varepsilon$ models under flow of a flat plate at high turbulence intensity have been compared with the test experimental data on velocity and turbulence intensity profiles.