Basics of Usual Turbulent Boundary Layer; Neutrally Stratified Atmospheric Boundary Layer

Abstract

Turbulent flow above the solid surface in different geometries, form example, pipe, channel and flat plate, resemble each other and show universality in dynamics to a large extent. Therefore, the descriptions of the flow in close proximity of walls in these geometries indicate similar characteristics. It is also convenient to obtain experimental results in these flows for verification of the theoretical ideas. Thus we have improved our knowledge of flow by studying these flows. However, the complex turbulent flow over the surface of the earth can be approximated by the flow over the half-space of a flat plate for the special case of a neutrally stratified fluid.The atmosphere is sometimes stratified neutrally. This condition of the atmospheric boundary layer corresponds to the usual type of boundary layer we know. Consequently it would be necessary to understand the basics of the ordinary boundary layer before proceeding to investigate the complex atmospheric boundary layer in its entirety. We follow Monin ad Yaglom (1979) for most of the ideas in this chapter.