COUPLING BETWEEN POTENTIAL FLOW AND BOUNDARY LAYER SOLVERS

As was mentioned in the introduction to this chapter, the solution of the complete flowfield requires the solution of the outer potential flow and the inner viscous boundary layer (near the solid surface). Typical information that can be obtained by the solution of the attached boundary layer problem is

1. Displacement effects due to the slower velocity inside the boundary layer.

2. Surface skin friction, so that the contribution of friction to the drag force can be estimated.

3. Indications about the tendency of the flow to detach (or separate). If the boundary layer does separate then the boundary layer solution beyond the separation point cannot be calculated (without using more complete viscous flow equations or interaction techniques).

In this section these topics will be discussed very briefly, too, and a more comprehensive description of them can be found in books dealing with viscous flows and boundary layers (e. g., Schlichting,1 6 AGARD CP-291,14 2 etc.).