The Wankel engine  

   The Wankel engine is a form of heat engine which has a rotary piston. In other words, instead of going up and down the Wankal piston rotates in the cylinder. Both cylinder and piston are quite different in the shape from those of conventional engines. The Wankel piston is triangular with curved sides and the cylinder is roughly oval in shape. The piston has an inner bore which is linked through a gear to the outputshaft.
     The piston thus forms three hook-shaped spaces between itself and the cylinder wall, wich very in size as the piston rotates. Fuel enters the cylinder through the inlet port when one of these spaces is increasing in size. The fuel trapped in this sectionn is then compressed by the turning piston and ingited by the sparking plug. The expanding gases subject the piston to a twisting moment which makes the piston revolve further until the exhaust gases escape through the exhaust port.
     The Wankel engine has many advantages over other conventional engines. Fewer moving parts are necessary because it produces a rotary movement without using a connecting rod and a crankshaft. Because of thus rotary movement it has no vibration. In addition it has no valves, it is smaller and lighter than conventional engines of the same power, and it runs economically on diesel and several other fuels.