The fluid dynamical aspects of the control of free vortices emanating from the wing or other parts of a flight vehicle are reviewed. Simple calculations based on slender-body theory are used to demonstrate the importance of controlling the strength, position and core stability and thickness of such vortices. From the equations describing vortex motion, conclusions are drawn as to how vortex properties can be influenced. In particular, a one-dimensional flow model for the vortex core flow is explored to identify the factors important in the determination of core thickness and stability. Simple energy arguments are used to clarify the phenomenon of vortex bursting and to draw conclusions as to what can be done to prevent or induce bursting. Examples of engineering applications of vortex control are given. In particular, recent advanced control schemes employed for the Saab A37 “Viggen” are described.
KeywordsVortex Core Vortex Breakdown Delta Wing Wing Surface Vortex Strength
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