Felix Wankel

Felix Wankel

Felix Wankel

German engineer Felix Wankel is best known for his invention of the Wankel engine. The Wankel engine is a gasoline-powered engine that is more powerful than the engines usually used in automobiles.

Felix Wankel (1902-1988), German engineer, best known for inventing the Wankel engine. Sometimes called the Wankel rotary engine, the Wankel engine uses a turning rotor inside a housing instead of pistons to provide power. It is more powerful and easier to maintain than a traditional internal-combustion engine of the same size.

Born the son of a forestry official in the Black Forest of Germany, Wankel never pursued a higher education. He did, however, show great skills in engineering and mathematics as well as an intense interest in vehicle propulsion. He began developing an engine around 1927, having in mind a novel design for gasoline-powered, internal-combustion engines. He received his first patent in 1929, for plans he made for a rotary engine.

The main parts of Wankel’s engine are a roughly cylindrical chamber and a triangular rotor with rounded edges. The chamber’s cross-section is actually an ellipse, or an elongated circle, instead of a perfect circle. The chamber has two openings on one of the ellipse’s long sides. One allows fuel to flow into the chamber and the other allows exhaust to escape. A spark plug, a device that uses a strong electric current to produce a spark between two electrodes, is centered on the other long side of the chamber. The rotor’s corners fit snugly against the sides of the chamber, effectively dividing the chamber into three parts. As the rotor turns, it draws in fuel in one chamber, compresses the fuel until the spark plug ignites the fuel and burns it in the second chamber, and allows the byproducts of combustion to escape from the third chamber. The burning, expanding fuel gases forces the rotor to turn. The rotor is usually connected directly to a driveshaft. The engine’s simplicity makes it lighter and more powerful than a traditional Otto-cycle internal-combustion engine. However, it uses fuel faster than an equivalent Otto-cycle engine, and it releases more exhaust.

Wankel joined the National Socialist German Workers' Party (Nationalsozialistische Deutsche Arbeiterpartei, or NSDAP) in the 1920s but left the party in 1932, before the Nazis came to power. Conflicts with local Nazi officials led to his arrest and imprisonment for several months in 1933. After his release, he worked for the German Aeronautical Research Establishment, where he refined his rotary piston engine design. When the Allies invaded Germany in 1945 during the final stage of World War II, Wankel was captured and held as a prisoner of war in France until 1946.

After his release, it took Wankel several years to rebuild a research program. He gained the support of the German motorcycle manufacturer Neckarsulm Strickmaschinen Union (Neckarsulm Knitting-machine Union, or NSU) in 1951. Wankel finally produced a fully functional prototype of a rotary engine in 1956. In 1957 he formed a company called Wankel GmbH to license the design of his engine, and other companies paid Wankel GmbH for the right to used the rotary engine. Wankel sold his company in 1971. The company now builds rotary engines, used mostly for aircraft and go-carts. Wankel created Technische Entwicklungsstelle (Center for Technical Advancement, or TES) in 1976 as a research institute. German industrial company Daimler-Benz bought TES in 1986.

Major companies in several countries commercially developed the Wankel engine. The German manufacturer NSU used the engine in boats and several models of cars. The NSU used the engine in its R0 80 luxury sedan in the 1960s, but it showed problems of high fuel consumption and exhaust pollution. The Japanese automobile maker Mazda used it in sports cars, most notably the RX-7, from the 1970s to the 1990s. The Wankel engine has also been used by high-performance motorcycle makers.

Wider use of the Wankel engine remains possible if the high fuel consumption and exhaust pollution problems can be resolved. The Wankel engine is still the most radical innovation in hydrocarbon internal combustion engines since the familiar Otto-cycle internal- combustion engine was developed in the 19th century. Tests in the 1990s showed that the rotary engine burns liquid hydrogen well. Hydrogen exhaust would be harmless, unlike the exhaust from petroleum-based fuel. Liquid hydrogen is difficult and expensive to produce and store, but if it ever becomes a common fuel, the Wankel engine could become much more practical.

Wankel Engine motor

Wankel Engine

Wankel Engine, internal-combustion engine, powered by gasoline, that uses a triangular-shaped rotor, or rotating part, to produce mechanical energy. Traditional internal-combustion engines use pistons (solid cylinders moving within a closely fitted casing) instead of a rotor. The Wankel engine is powerful for its weight and size, vibrates much less than piston engines, has few moving parts, and can run comparatively quietly and smoothly on different grades of fuel. The engine is named after German engineer Felix Wankel for his contribution to the engine’s development in the 1950s.

The Wankel engine produces rotary motion by directly powering a main driveshaft, instead of powering pistons that indirectly drive a main driveshaft. The rotor of the Wankel engine is encased in an oval-shaped housing. Although all three points of the triangular rotor remain in tight contact with the housing wall, space remains between the sides of the rotor and the housing wall. When the rotor turns, gasoline is pulled into the housing through an intake port and trapped between one side of the rotor and the housing wall. It compresses as the rotor continues to turn. The trapped gas is then carried past a spark plug and ignited, releasing the energy that moves the rotor. The rotor moves the spent gas and air to an exhaust port, sending it quickly out of the housing. Each of the three sides of a Wankel engine’s rotor constantly drives the shaft. When the rotor moves one-third of the distance around its center, the main drive shaft rotates one complete turn.

Felix Wankel researched internal-combustion engines in the 1930s. During World War II (1939-1945) he worked in aeronautical research, but after the war he continued his research on engines. He produced a successful prototype of the engine during the mid-1950s. The first automobile fitted with a Wankel engine was the Spyder produced during the mid-1960s by the company NSU (Neckarsulmer Strickmaschinen Union).

In addition to automobiles, the Wankel engine has been used successfully in trucks, boats, electric generators, golf carts, lawn mowers, snowmobiles, and motorcycles. The aircraft industry has also shown interest in the engine, since it is small and more easily serviceable than piston engines. Use of the Wankel engine, however, has been limited by the engine’s comparatively high fuel consumption and exhaust emissions.

Wankel engine

Wan·kel en·gine [wángk'l ènjin] (plural Wan·kel en·gines) noun internal-combustion engine without pistons: an internal-combustion engine in which an approximately triangular rotor inside an elliptical combustion chamber replaces the pistons of a conventional engine, thus reducing the number of moving parts [Mid-20th century. After Felix Wankel (1902-1988), German engineer]