Modeling ship screw propeller heliciel
ship screw propeller historyWe have seen in the history of the screw propeller emerge gradually the shape of the current propeller.
Here we will make a (very) fast enumeration, of course incomplete, different technical developments in boat propellers, between 1750 and 1900, to become aware of what has been done by our fathers.... before seeing ways of screw propeller propulsion , currently used on boats.In 1752 the Academy of Sciences of Paris offered a range of prices that brought a significant contribution in the shipbuilding .Bernoulli, Euler, D'Alembert worked on the problem. Bernoulli proposed a screw propeller which won a prize and who looked like this:
Bernoulli 175230 years later, Bramah offers a system with a screw propeller shaft located below the waterline as this:
Bramah 1785In 1802 Shorter offers a propeller that could propel sailboats when great calm .The shaft propeller remaining above the waterline no waterproofing was necessary. This ship screw propeller was intended to be manipulated by men using a capstan.
Shorter 1802In 1836 Erricson draws a contra rotating ship screw propeller:
Taylor 18381849 Griffith draws a self-propeller (variable pitch) which could set flag:
1849 Griffith1851 Mangin attempts to increase the thrust of the screw propeller blade separating into two portions
In 1860, Hirsh filed a patent on a ship screw propeller possessing a ditribution of twisting, but also distribution of the radial positioning angle of the profiles::
Griffith in 1871 resumed the idea of Mangin separate the blade in two, but only a portion of the blade of the screw propeller:
Zeise in 1886, continued the development of the distribution of the pitch, increasing the pitch of the elements near the blade root, in order to increase the efficiency of the propeller area.
1901 Zeise experimenting screw propellers, with flexible blades:
In 1907 Taylor injects air on the upper surface of the blade of the screw propeller to reduce cavitation:
Innumerable other attempts and experiments in propellers, of course, been carried, we flew over quickly the evolution of the shape of boat propellers.Nowadays, the shape of the screw propellers is still evolving, and system invented to increase performance are numerous .Proof if it were needed, that the history of the screw propeller is far from complete ....