What is another name for an Otto engine?

An Otto engine is the same as spark combustion engine, invented by German engineer Nikolaus Otto. It uses easily gasifiable fuel, such as ethanol, petrol or liquid natural gas, which is mixed with air, compressed and ignited by a spark created by spark plug. Its assets are easy manufacture, light weight and great range of revolutions and torque. Its liabilities are need of electric source, worse thermal efficiency than other internal combustion engines and need of more expensive fuels than other types of engines.

The first Otto engine was run on coal gas in 1889. It quickly superseded other gas engines such as the Lenoir engine, and Karl Benz chose it as the power source of the world's first automobile in 1885. It ran on liquid fuel.

Spark combustion engines follow the Otto cycle, where isothermal and isenthropic processes follow each other. They can be either two-stroke or four-stroke engines, and they are used on work machines, automobiles, motorcycles, powerboats and aircraft.

A compression ignition engine is the same as Diesel engine. A turbocompound engine uses a combustion engine to operate a turbine. An external combustion engine is either a steam engine, Stirling engine or a turbine engine.