Internal Combustion Engine

The internal combustion engine is a heat engine in which the burning of a fuel occurs in a confined space called a combustion chamber. This exothermic reaction of a fuel with an oxidizer creates gases of high temperature and pressure, which are permitted to expand. The defining feature of an internal combustion engine is that useful work is performed by the expanding hot gases acting directly to cause movement, for example by acting on pistons, rotors, or even by pressing on and moving the entire engine itself.

This contrasts with external combustion engines such as steam engines which use the combustion process to heat a separate working fluid, typically water or steam, which then in turn does work, for example by pressing on a steam actuated piston.

The term Internal Combustion Engine (ICE) is almost always used to refer specifically to reciprocating engines, Wankel engines and similar designs in which combustion is intermittent. However, continuous combustion engines, such as Jet engines, most rockets and many gas turbines are also very definitely internal combustion engines.


The first internal combustion engines did not have compression, but ran on an air/fuel mixture sucked or blown in during the first part of the intake stroke. The most significant distinction between modern internal combustion engines and the early designs is the use of compression and, in particular, in-cylinder compression.

  • 1206: Al-Jazari described a double-acting reciprocating piston pump with a crankshaft-connecting rod mechanism.
  • 1509: Leonardo da Vinci described a compressionless engine.
  • 1673: Christiaan Huygens described a compressionless engine.
  • 17th century: English inventor Sir Samuel Morland used gunpowder to drive water pumps, essentially creating the first rudimentary internal combustion engine.
  • 1780's: Alessandro Volta built a toy electric pistol ([1]) in which an electric spark exploded a mixture of air and hydrogen, firing a cork from the end of the gun.
  • 1794: Robert Street built a compressionless engine whose principle of operation would dominate for nearly a century.
  • 1806: Swiss engineer François Isaac de Rivaz built an internal combustion engine powered by a mixture of hydrogen and oxygen.
  • 1823: Samuel Brown patented the first internal combustion engine to be applied industrially. It was compressionless and based on what Hardenberg calls the "Leonardo cycle," which, as the name implies, was already out of date at that time.
  • 1824: French physicist Sadi Carnot established the thermodynamic theory of idealized heat engines. This scientifically established the need for compression to increase the difference between the upper and lower working temperatures.
  • 1826 April 1: The American Samuel Morey received a patent for a compressionless "Gas or Vapor Engine."
  • 1838: a patent was granted to William Barnet (English). This was the first recorded suggestion of in-cylinder compression.
  • 1854: The Italians Eugenio Barsanti and Felice Matteucci patented the first working efficient internal combustion engine in London (pt. Num. 1072) but did not go into production with it. It was similar in concept to the successful Otto Langen indirect engine, but wasn't so well worked out in detail.
  • 1856: in Florence at Fonderia del Pignone (now Nuovo Pignone, a subsidiary of General Electric), Pietro Benini realized a working prototype of the Barsanti-Matteucci engine, supplying 5 HP. In subsequent years he developed more powerful engines—with one or two pistons—which served as steady power sources, replacing steam engines.
  • 1860: Belgian Jean Joseph Etienne Lenoir (1822–1900) produced a gas-fired internal combustion engine similar in appearance to a horizontal double-acting steam beam engine, with cylinders, pistons, connecting rods, and flywheel in which the gas essentially took the place of the steam. This was the first internal combustion engine to be produced in numbers.
  • 1862: German inventor Nikolaus Otto designed an indirect-acting free-piston compressionless engine whose greater efficiency won the support of Langen and then most of the market, which at that time was mostly for small stationary engines fueled by lighting gas.
  • 1870: In Vienna, Siegfried Marcus put the first mobile gasoline engine on a handcart.
  • 1876: Nikolaus Otto, working with Gottlieb Daimler and Wilhelm Maybach, developed a practical four-stroke cycle (Otto cycle) engine. The German courts, however, did not hold his patent to cover all in-cylinder compression engines or even the four-stroke cycle, and after this decision, in-cylinder compression became universal.
  • 1879: Karl Benz, working independently, was granted a patent for his internal combustion engine, a reliable two-stroke gas engine, based on Nikolaus Otto's design of the four-stroke engine. Later, Benz designed and built his own four-stroke engine that was used in his automobiles, which became the first automobiles in production.
  • 1882: James Atkinson invented the Atkinson cycle engine. Atkinson’s engine had one power phase per revolution together with different intake and expansion volumes, making it more efficient than the Otto cycle.
  • 1891: Herbert Akroyd Stuart built his oil engine, leasing rights to Hornsby of England to build them. They built the first cold-start compression-ignition engines. In 1892, they installed the first ones in a water pumping station. In the same year, an experimental higher-pressure version produced self-sustaining ignition through compression alone.
  • 1892: Rudolf Diesel developed his Carnot heat engine type motor burning powdered coal dust.
  • 1893 February 23: Rudolf Diesel received a patent for the diesel engine.
  • 1896: Karl Benz invented the boxer engine, also known as the horizontally opposed engine, in which the corresponding pistons reach top dead center at the same time, thus balancing each other in momentum.
  • 1900: Rudolf Diesel demonstrated the diesel engine in the 1900 Exposition Universelle (World's Fair) using peanut oil (see biodiesel).
  • 1900: Wilhelm Maybach designed an engine built at Daimler Motoren Gesellschaft—following the specifications of Emil Jellinek—who required the engine to be named Daimler-Mercedes after his daughter. In 1902 automobiles with that engine were put into production by DMG.
  • 1908: New Zealand inventor, Ernest Godward started a motorcycle business in Invercargill and fitted the imported bikes with his own invention – a petrol economiser. His economisers worked as well in cars as they did in motorcycles.


Internal combustion engines are most commonly used for mobile propulsion systems. In mobile scenarios internal combustion is advantageous, since it can provide high power to weight ratios together with excellent fuel energy-density. These engines have appeared in almost all automobiles, motorbikes, many boats, and in a wide variety of aircraft and locomotives. Where very high power is required, such as jet aircraft, helicopters and large ships, they appear mostly in the form of gas turbines. They are also used for electric generators and by industry.

Internal combustion mechanics

The potato cannon uses basic principles behind any reciprocating internal combustion engine: If a tiny amount of high-energy fuel (like gasoline) is put into a small, enclosed space and ignited, an incredible amount of energy is released in the form of expanding gas. That energy can be used to propel a potato 500 feet. In this case, the energy is translated into potato motion. It can also be used for more interesting purposes. For example, a cycle can be created that allows one to set off explosions like this hundreds of times per minute, and if that energy can be harnessed in a useful way, it is the same as the core of a car engine!

Almost all cars currently use what is called a four-stroke combustion cycle to convert gasoline into motion. The four-stroke approach is also known as the Otto cycle, in honor of Nikolaus Otto, who invented it in 1867. The four strokes are:

  1. Intake stroke
  2. Compression stroke
  3. Combustion stroke
  4. Exhaust stroke