Rotary Engine Facts:
From Wikipedia, the free encyclopedia
A Wankel engine in Deutsches Museum Munich, GermanyThe Wankel engine is a type of internal combustion engine which uses a rotary design to convert pressure into a rotating motion instead of using reciprocating pistons. Its four-stroke cycle is generally generated in a space between the inside of an oval-like epitrochoid-shaped housing and a roughly triangular rotor. This design delivers smooth high-rpm power from a compact, lightweight engine.
The engine was invented by German engineer Felix Wankel. He began its development in the early 1950s at NSU Motorenwerke AG (NSU) before completing a working, running prototype in 1957. NSU then subsequently licenced the concept to other companies across the globe, who added more efforts and improvements in the 1950s and 1960s.
Because of their compact, lightweight design, Wankel rotary engines have been installed in a variety of vehicles and devices such as automobiles and racing cars, aircraft, go-karts, personal water crafts, and auxiliary power units.
The RENESIS engine ? also 13B-MSP, for Multi Side Port ?, which first appeared in production in the 2003 Mazda RX-8, is an evolution of the previous 13B. It was designed to reduce exhaust emission and improve fuel economy, which were two of the most recurrent drawbacks of rotary engines. Unlike its predecessors from the 13B range, it is naturally aspirated, leading to lower power from its two versions (Mazda RX-7's twin-turbocharged 13B-REW (280hp).
The engine entailed two major changes. First, the exhausts ports are no longer peripheral but are located on the side of the housing, which allowed engineers to eliminate overlap and redesign the intake port area. This produced noticeably more power, thanks to a better compression ratio. Second, the rotors are shaped differently, especially their side seals and low-height apex seals, which offer optimized lubrication.
These and other innovative technologies allow the RENESIS to achieve 49% higher output and dramatically reduced fuel consumption and emissions (the RX-8 meets LEV-II). It won International Engine of the Year and Best New Engine awards 2003 and also holds the "2.5 to 3 litre" size award for 2003 and 2004, where it is considered a 2.60 L engine. Finally, it was on the Ward's 10 Best Engines list for 2004 and 2005.
The RENESIS has also been adapted for a dual-fuel use, allowing it to run either on gasoline or hydrogen.