How it works    Wankel engine works in an Otto cycle that means it has Intake, Compression, Ignition and Exhaust. These four strokes occur between the walls of the rotor and housing. The oval shaped housing is made so that the compression ratio is maximized.  Instead of crankshaft there is a eccentric shaft, which goes through centers of both rotors and connects them. Both rotors rotate around in orbital revolutions. To make sure sure that the rotor makes a third of a turn when eccentric shaft makes one, the rotors are supported by ring gear, which is mounted onto the housing of the engine plate.This also prevents the rotor from rubbing the walls of the housing. One of the engineering challanges with this engine was to seal chambers. Here its much more complicated compared to piston engine. Not only the edges have to seal, but also the top and bottom of the rotor. Thats where apex seals come into play. They are locate on the very edge of the rotor and on the top and bottom.These are made out either coated cast iron, aluminium-filled carbon or ceramic. In order to maintain a good seal in low RPM these seals have a spring under them, so they are constantly pushed against the housing.