## Wankel Engine Cars: History, Design, and Performance
The Wankel engine, also known as the rotary engine, is a unique type of internal combustion engine that has a rotating triangular rotor instead of the traditional reciprocating pistons. This design offers several advantages, including a smoother and more powerful operation, as well as a more compact size and weight.
### History of the Wankel Engine
The Wankel engine was invented by German engineer Felix Wankel in the 1950s. Wankel was inspired by the smooth operation of the rotary engine used in the NSU Prinz motorcycle, and he believed that a similar design could be adapted for use in automobiles.
In 1954, Wankel partnered with NSU to develop a rotary engine for automotive use. The first successful Wankel engine was built in 1957, and the first Wankel-powered car, the NSU Spider, was introduced in 1964.
### Design of the Wankel Engine
The Wankel engine has a unique design that differs significantly from traditional reciprocating piston engines. The core components of a Wankel engine include:
– **Rotor:** A triangular-shaped rotor that spins within a figure-8-shaped chamber.
– **Chamber:** A figure-8-shaped cavity that houses the rotor and forms the combustion chamber.
– **Eccentric Shaft:** An offset shaft connected to the rotor that converts its rotary motion into torque.
– **Intake and Exhaust Ports:** Ports in the chamber that allow the intake and exhaust of air-fuel mixture and exhaust gases, respectively.
As the rotor spins within the chamber, it creates three separate combustion chambers that move through the intake, compression, power, and exhaust strokes. The unique shape of the rotor and chamber allows for a continuous combustion cycle, resulting in a smooth and powerful operation.
### Advantages of the Wankel Engine
The Wankel engine offers several advantages over traditional piston engines, including:
– **Smoothness:** The continuous combustion cycle eliminates the reciprocating motion of pistons, resulting in a smoother and quieter operation.
– **Power:** The Wankel engine produces more power per liter of displacement than piston engines, due to its higher combustion efficiency and compact size.
– **Compactness:** The Wankel engine is significantly smaller and lighter than piston engines with comparable power output.
– **Reliability:** Wankel engines are generally regarded as reliable, with a long service life.
### Disadvantages of the Wankel Engine
Despite its advantages, the Wankel engine also has some disadvantages, including:
– **Fuel Economy:** Wankel engines tend to have lower fuel economy than piston engines, due to their increased friction and higher heat loss.
– **Emissions:** Wankel engines produce more emissions than piston engines, particularly hydrocarbons and nitrogen oxides.
– **Apex Seal Wear:** The apex seals that form the combustion chamber in Wankel engines can wear over time, leading to reduced power and increased emissions.
– **Production Costs:** Wankel engines are more expensive to manufacture than piston engines due to their complex design and the need for specialized materials.
### Wankel Engine Cars
The Wankel engine has been used in a number of production cars over the years, including several iconic models from Mazda. Here are some of the most notable Wankel-powered cars:
– **NSU Spider (1964):** The first production car equipped with a Wankel engine.
– **Mazda Cosmo Sport 110S (1967):** The first mass-produced Wankel-powered car.
– **Mazda RX-7 (1978-2002):** One of the most popular and successful Wankel-powered cars, known for its high performance and sporty handling.
– **Mazda RX-8 (2003-2012):** The last production car to be equipped with a Wankel engine.
– **Hydrogen RX-8 (2009):** A prototype version of the RX-8 that ran on hydrogen fuel.
### Conclusion
The Wankel engine is a unique and fascinating type of internal combustion engine that offers several advantages over traditional piston engines. Its smooth operation, high power output, and compact size make it an attractive choice for automotive applications. However, its lower fuel economy, higher emissions, and apex seal wear issues have limited its widespread adoption. Despite its challenges, the Wankel engine remains a symbol of engineering innovation and has left a lasting legacy in the automotive industry.
