Boundary Layer Vorticity and the Rise of “Hairpins”
نویسنده
چکیده
The downstream evolution of the vorticity field in the vicinity of hairpinshaped regions of rotational motion appearing in the transitioning boundary layer is examined. It is shown that the dynamics of hairpins is inseparable from that of the non-rotational vorticity out of which they develop in a self-reinforcing process of ejection and reorientation. Widening the concept of structure to include the complete localized vorticity that produces hairpins, allows for a more complete and selfcontained explanation of the boundary layer physics.
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