HISTORY OF THE PROPELLER |
|
In 1752 Bernoulli suggested propelling boats, by putting vanes in a 60° axis, and since then, some modifications have been made on the propeller’s types in accordance to the innovations made to marine crafts. (Figure 1). |
From the desktop of
Antonio Vazquez |
|
Figure 2 shows the development that the propellers have presented regarding to the geometry of the blades from the year 1800 to 1880. |
|
|
In
1878 William Froude developed the theory of a propeller blade’s
elements, which reflects the generated efforts on each section of the
blade. (figure 3). |
Figure 4 reflects the distribution of the generated efforts in the blades of a propeller with an ogival-section and another one with an airfoil-section It
could be considered that the development of this theory was the
foundation for developing several types of propellers used in the
marine area nowadays. There
are many types of propellers that have been getting better through the
years, as well as the materials which the propellers are manufactured
with. These materials are: Stainless
Steel and Bronze, which have a very high resistance to corrosion. Some
of the propeller’s types designed in the last few years are
presented next in three different Bronze Alloys |
NOVA DUCTED IN MANGANESE BRONZE |
NOVA DUCTED IN ALUMINUM BRONZE |
NOVA FREE IN AQUALLOY BRONZE |
|
If you have
any questions or any suggestions to any subject in these technical issues
or If you want to be removed from this mailing list, please send an e-mail
with your comments to technicalletter@ricepropulsion.com
|