I   Global Issues  I  Piston Engine  I Wankel Engin  I

  BACKGROUND   

Wankel Engine

With its simple structure, higher power-to-weight ratio, little inertia losses, good acceleration characteristic and dynamic balance, the rotary engine is an idea that many inventors have been keen to study in the past 100 years. Looking back at the engine's history, we can find that there are approximate 2000 people engaged in the invention of rotary engines. A successful example is known as the "Wankel Rotary Engine" built by the German engineer Felix Wankel in 1954. As for other designs, with complicated or unreasonable structure,  great heat or pressure losses, lower efficiency, and difficulty in sealing and manufacture, they have been ignored by society and have became valueless. 

Although the "Wankel Rotary Engine" features simplified the structure, reduced the weight and size, and had fewer moving parts, it consumes a lot of oil and results in very heavy pollution. Its principle and structure which is extremely high surface-to-volume ratio of the combustion chamber with a narrow-long section of flame propagation, results in the quenching effect being much higher and the burning far from being completed. In fact, part of emissions are from leakage of the apex seal when explosion occurs, because it works along the single line shape of the seal. There are also other disadvantages like poor function on low-speed range and difficulty in lubrication etc. 

Twenty years' practice has proved that this sort of engine is not good enough to compete with the conventional piston engines, which as a result were eliminated in the 1970's. Because it has a higher power-to-weight ratio and simple structure, some engine makers are still interested in producing Wankel Rotaries for special use in aviation & UAVs, or car speeding. Mazda is the biggest manufacturer of the Wankel Rotaries in the world. You can learn more about the Wankel Rotary Engines on https://www.mazda.com