Calculation of the Strength of Vortex Currents Induced by Vortex Generators on Flat Plates and the Evaluation of Their Performance

Abstract

Vortex generators are used to overturn the momentum of the flow in the boundary layer, thereby preventing flow separation, and are broadly used in aviation, wind power, heat exchange, and different fields. It has been determined that the capability of an eddy current generator to manipulate the boundary layer is proportional to the intensity of the vortex strength it excites. Although the mathematical notion of vortex strength is very well defined, there are difficulties in figuring out vortex strength in applications. This article proposes a calculation method based on confidence intervals and contour eddy current intensity. Meanwhile, the contemporary overall performance evaluation of vortex generators is frequently obtained in a roundabout way through their consequences on feature factors (e.g., lift coefficients, etc.), and techniques for the direct assessment of a vortex generator’s overall performance are no longer available. To address this situation, the article derives the performance evaluation criterion of the equal height vortex generators, the harmonic intensity factor (K=ωpeak r′), based on the Biot–Savart theorem.

Keywords

• vortex generators
• effect of boundary layer control
• vortex strength
• Biot–Savart theorem