Accession Number:

ADP004057

Title:

Modelling Circulation Control by Blowing

Descriptive Note:

Corporate Author:

SOUTHAMPTON UNIV (UNITED KINGDOM)

Report Date:

1984-08-01

Pagination or Media Count:

12.0

Abstract:

This paper describes a new theoretical representation of circulation control based on discrete vortex modelling techniques. The application of discrete vortex modelling to the prediction of circulation control is initially presented for the Coanda flow of a wall jet around a circular cylinder in a free stream. The decay in the jet momentum, due to viscous and entrainment effects, has been represented in the model by decaying the strength of each vortex as it flows downstream from the slot. The models application has then been extended to predict the effect of circulation control on other shapes of aerofoil. The paper includes the application of the model to an elliptic section as an example of any aerofoil section that can be represented in a potential flow. The model has had considerable success in predicting the lift produced from such bodies due to the jet, but information about the drag requires additional modelling of the surface boundary layer. A similar technique has been used to represent the boundary layer by discrete vortices and doublets. The models prediction has been compared with the experimental data of an unblown circular cylinder.

Subject Categories:

  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE