ANSYS Roots type Supercharger

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The Roots type supercharger shown below is used to boost the intake pressure
of an internal combustion engine by approximately 12-15 PSI, drastically
improving the performance of the engine.The device consists of two rotor
assemblies turning in opposite directions.The air is pushed around the outside
of the rotors and out the bottom. Air can??t leak back up through the rotors due
to the close clearances between the rotors and the case.The outer surface of
each rotor lobe contains a Teflon seal strip to prevent leakage.In order to
reduce pulsing of the pressure, the lobes are often twisted along the rotational
axis, or helically, as shown below.