Расчетно-экспериментальное исследование обтекания тел с вихревыми ячейками

Abstract

Vortex cell is a certain artificial impression (cavity) on a smooth surface, for example, an aerofoil. If a viscous flow smoothly wraps the surface in front and behind the cell so no flow separation occurs, such cell is defined as a working vortex cell. Intensive flow recirculation that inevitably occurs in a working vortex cell is referred to as trapped vortex. It is possible to say that a working vortex cell is a cell with a started trapped vortex. The main goal of installing vortex cells on a surface is to avoid the boundary-layer separation. The boundary layer has a tendency to separate in the areas of the surface that experience an increase in pressure, or, in other words, where adverse pressure gradient exists. Therefore, the major practical quality of the vortex cell should be its ability to remain “working” under the largest possible adverse pressure gradient. Efficiency of several methods for influencing the flow in the vortex cell was investigated. These methods are:deterministic suction with constant suction flow rate; periodic suction with feedback control based on pressure data; periodic suction from the center of the cell; periodic impulse supply.