In our last post on nacelle strake vortices, the Zone Theory of Lift was proven beyond any doubts, as the vortices showed the existence of the pressure zones. In this post we analyze the curious behaviour of these strake vortices, and the path they take over the wing after formation at the nacelle strakes of a typical jet engine. Nacelle Strake Vortices Never Go Under the Wings … Why ?
You will notice that the strakes are at a lower point on the engine nacelle, well below the wing and theoretically a vortex produced here shouldn’t rise up towards the wing top, as in above picture. It should proceed in a straight line under the wing (red dotted line in figure below). After all, the streamlines flow on both sides, i.e., over and under a wing … Right ? … Also, especially since there is such a large volume of air being pushed by the engines its intuitive to think that the vortices should get sucked along the “streamlines” under the wing, due to venturi effect of the jet exhaust ! … No?
But what happens is the exact opposite, and we notice that all vortices follow an S-shaped path from the bottom to the top of the wing (as shown as blue solid arrow line in above diagram, and also in pic on top). No vortex travels under the wings. Neither does any “streamline” or else it would have carried the vortex with it … 🙂
This is very interesting, and further proves that the forward subduction zone is so dominant on the air mass ahead of the wing, that it forces the vortices to jump up and around the zone envelope, and then over the top of the wing, in S-shaped paths. The existence of pressure zones is proven beyond the shadow of any doubt, once more.
Even if we accept that there’s some kind of streamline flow over and under a wing, the fact that the nacelle strake vortex jumps lane and moves to the top, is not possible by any means, and therefore flow argument is totally baseless. The correct explanation of vortex path jumping behaviour is the one given by the Zone-Theory, as already mentioned in several posts on this website.
If streamline flow exists, the vortex behaviour shown by red arrow in above figure should never happen under any circumstances. This conclusively proves complete absence of any kind of “streamline flow” in real atmospheric flight conditions.
Bonus feature 🙂 : This anomaly can’t even be replicated in a Wind-Tunnel nor predicted in any Computational Fluid Dynamics (CFD) simulation. Only the zone theory can accurately explain this weird lane-jump as shown below:
