Photo : - Mazda Motor Europe

Mazda celebrate their 90th anniversary this year. It was this manufacturer's innovative spirit that kept alive one of the most revolutionary technologies in the history of the automobile. Once thought to be doomed to certain death due to the high cost of manufacture, the rotary engine is being given a breath of fresh 'air' with hydrogen.

After WW2, a German inventor Felix Wankel, who had never obtained a driver's license or even a university degree, dreamt of creating a non-reciprocating engine comprising a combustion chamber plate and a thin disk rotating in the middle. He developed the invention which was at that time still only theoretical, but the Japanese manufacturer Mazda were so impressed by concept of the engine they bought the patent in 1961. But the original "Wankel" produced in Hiroshima vibrated so much that it caused cracks in the inner walls of the rotor, a weakness that engineers were able to solve by improving the sealing technology and lubrication. This engine is distinguished by both its flexibility and high crankshaft speed. Mazda has had enough confidence in this technology to power nearly two million of its vehicles, including the Mazda 787B which won the 24 Hours of Le Mans in 1991.

In 1990 Mazda engineers combined hydrogen fuel with their rotary engine and they were pleasantly surprised. The Mazda rotary engine has several advantages over conventional piston engines running on hydrogen. The air / hydrogen mix is more appropriate as the inlet process lasts longer, ensuring better performance. Furthermore, the rotary engine excludes any potential for backfire because its inlet chamber is separated from the combustion chamber and remains cold, there is no intake valve or exhaust to be brought to ambient temperature During the past twenty years, Mazda has developed its hydrogen rotary engine for mass production. There are Mazda hydrogen powered engines are now available to rent; RX-8 Hydrogen RE et Mazda 5 Hydrogen RE hybrid.

Julien Hergault – Translated by Dave Davies