Screw turbine
Archimedes screw generators operate in a wide range of flows (0.01
Water flows freely off the end of the screw into the river.
The upper end of the screw is connected to a generator through a gearbox.
The Archimedean screw is an ancient invention, attributed to Archimedes of Syracuse (287–212 BC.
), and commonly used to raise water from a watercourse for irrigation purposes.
In 1819 the French engineer Claude Louis Marie Henri Navier (1785–1836) suggested using the Archimedean screw as a type of water wheel.
In 1916 William Moerscher applied for a U.S. patent on the hydrodynamic screw turbine.
The Archimedean turbine may be used in situations where there is a stipulation for the preservation and care of the environment and wildlife.
An Archimedes Screw Turbine (AST) hydroelectricity powerplant can be considered as a system with three major components: a reservoir, a weir, and the AST (which is connected to the system by a control gate and trash rack).
Typically, a minimum flow over the weir is mandated for the protection of the local environment.
A comprehensive guide about the principles of designing Archimedes screw turbines and screw hydropower plants is available in "Archimedes Screw Turbines: A Sustainable Development Solution for Green and Renewable Energy Generation—A Review of Potential and Design Procedures".
[2] To design Archimedes screw turbines and hydropower plants, it is essential to estimate the amount of water is passing through the screw turbine since the amount of power generated by an Archimedes screw turbine is proportional to the volume flow rate of water through it.
To estimates the total flow rate passing through an Archimedes screw turbine for different rotation speeds (ω) and inlet water levels the following equation could be used:
for a wide range of small to full-scale AST sizes.
