turbolenza
May 13, 2007
The world first flow visualization representation above is a sketch of a free water jet issuing from a square hole into a pool, drawn by the hands of Leonardo da Vinci; circa 1500. In the view of John L. Lumley, Da Vinci might have prefigured the now famous Reynolds turbulence decomposition nearly 400 years prior to Osborne Reynolds’ own pipe-flow visualization! In one of his notebooks, da Vinci wrote (translated by Ugo Piomelli): “Observe the motion of the surface of the water, which resembles that of hair, which has two motions, of which one is caused by the weight of the hair, the other by the direction of the curls; thus the water has eddying motions, one part of which is due to the principal current, the other to the random and reverse motion.”
