reading some of Professor Goriely's summaries about whip physics, the first thing coming to my mind always was, that we don't cast a whip, but a fly rod. Biggest difference for me seems to be, that we have a fly line (depending on a) it's length outside the tip, b) taper, c) density and d) velocity relative to rod plane/direction, not to forget about the fly and leader as well) providing all different resistances against the rod's tip. This and the fact, that we are simply not casting our fly rod in a closed system, but one coming with so many variables, makes me think, that we cannot just apply the physics of a typical whip here. Nor do I think we can quantify the level of "whip effect" (for me it would be more of a fly rod effect) in general.
It seems to me no one of you fine physicists yet can answer Paul's simple question in a simple way. This makes me think to have a point?
Was there ever made a calculation or even better a slow motion study of the increase in tip speed for straightening when only moving the rod itself?
Gordy your great video about the increased level of counterflex when not having the line attached comes to my mind!
About the "pirouette effect" there are great videos explaining that effect in general. Easy understandable. Only as far as I understand they all refer to a system, which is not too far away from a closed system (coming with very little drag at the connection to the outer world of that system). Since this is very different for the fly cast (in which we always hold the rod in our hands and though add significant force), it yet doesn't convince me, it to be very helpful trying to add this effect into the explanantion of a fly cast. I just don't see at what point we have conserved the energy, but constantly adding more energy to the rod.
So I am wondering, if anyone can explain the whip effect, the pirouette effect and how they apply in fly casting in an easy understandable and most of all correct way. I take it, a correct explanantion among physicists would be the one not creating any further arguments among you fine guys?
Still hard for me to understand, why not looking directly at what happens in the fly cast instead of trying to apply principles, that never were written to be applied in understanding the fly cast. Yet this seems very complicated to me. You please tell me, if I am wrong.
No offense here of course. Just having a bit of a feeling, that explaining the fly cast doesn't have to be this complex, does it?