What is a rotary engine? What are the characteristics of a rotary engine compared to a traditional piston engine?
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What is a rotary engine?

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22. 02. 2026
What is a rotary engine? What are the characteristics of a rotary engine compared to a traditional piston engine?The rotary engine, also known as the Wankel engine, is a unique type of internal combustion engine used in vehicles. Its working principle is entirely different from the traditional piston engine we commonly refer to. Instead of the "up-and-down bouncing" of pistons, it utilizes a triangular rotor to "rotate" within the cylinder to generate power.. 
Chinese rotary engine

Rotary engine Main features:

The strengths and weaknesses of the rotary engine stem from these distinctive characteristics, which endow it with a fascinating genius on one hand, and a fatal flaw that has prevented its widespread adoption on the other.

Advantages: Small size, light weight, high power: This is what is known as an extremely high "power-to-weight ratio". The 1.3-liter twin-rotor engine of the Mazda RX-7 can extract 280 horsepower, demonstrating extremely powerful performance.

High-speed yet smooth, uniquely charming: It can easily rev up to nearly ten thousand revolutions per minute, and its operation is extremely smooth. The unique sound and power output characteristics have captivated countless car enthusiasts. Fatal flaw (why not popularized): High fuel consumption and poor emissions: these are its biggest weaknesses. Due to the elongated shape of the combustion chamber, fuel combustion is not sufficient, resulting in high fuel consumption and difficulty in meeting increasingly stringent environmental regulations. Mazda's RX-8 was therefore forced to be discontinued in 2010.

Durability is a concern: the sealing plate (diamond seal) at the top of the rotor experiences severe friction with the cylinder wall over time, which can easily lead to wear, resulting in air leaks and oil burning. Consequently, the lifespan of these engines is generally shorter than that of traditional engines. Low torque output: It has insufficient torque output at low RPMs, requiring higher RPMs to obtain strong power, which is inconvenient for daily driving.  

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