The German operators of the Enigma machines were told which three rotors and which settings to use each day, but they had to choose the starting positions of the rotors and indicate their choices via the first three letters of their first messages.
The improved performance is attributed to the favorable interaction between the rotors which accelerates the flow approaching the downstream rotors and generates higher turning moment in the direction of rotation of each rotor.
This feature has been realized using two coaxially aligned eccentric rotors, which are driven by DC motors independently.
The rotors, which have three blades, can swing out of the water for maintenance.
Further, by this methodology, a safe clearance between the two rotors is pre-determined.
Detailed measurements of total pressure, static pressure, velocity components and flow angles were carried out at the inlet of the first rotor, between the two rotors and at the exit of the second rotor using three seven hole probes.
The effect varies depending on the speed of the rotors, which can be toggled between fast (tremolo) and slow (chorale) using a console or pedal switch, with the most distinctive effect occurring as the speaker rotation speed changes.
For one thing, brake rotor replacement will probably become a thing of the past, as the carbon-ceramic rotors, which are extremely hard and wear minimally, might well outlast the car.
The leaks flow through clearances between a screw rotor and a stator, and clearances between two meshing rotors.
In this case study, a comparison between two wind rotors, designed with two different AR values (AR = 2 and AR = 0.4), will be presented.
