De Olifant, Burdaard Archimedes' screw. This Archimedes' screw has an axle diameter of and is diameter overall. It is inclined at an angle of 17½°. Each revolution of the screw lifts of water. The drive to the smaller of the two Archimedes' screws that drain the polder is from a 36 cog gear wheel meshing with the "great spur wheel". This drives a 33-cog gear wheel which drives the Archimedes' screw via a 41-cog gear wheel on the axle of the Archimedes' screw. This Archimedes' screw has an axle diameter of and is diameter overall. It is inclined at an angle of 121°.
Archimedes number Archimedes number In viscous fluid dynamics, the Archimedes number (Ar) (not to be confused with Archimedes' constant, π), named after the ancient Greek scientist Archimedes is used to determine the motion of fluids due to density differences. It is a dimensionless number defined as the ratio of external forces to internal viscous forces and has the form: where: When analyzing potentially mixed heat convection of a liquid, the Archimedes number parametrizes the relative strength of free and forced convection. When Ar » 1 natural convection dominates, i.e. less dense bodies rise and denser bodies sink, and when Ar « 1